World Bank Generic Data Collection Equipment Spec - 07 01 09 Road Data Collection Equipment Generic Specificationv1.1

Generic Equipment Specification

Multi-Function Road Data Collection System

Version 1.1 – 9 January 2007

East Asia Pacific Transport Unit
The World Bank
Washington, D.C.

The World Bank
East Asia Transport Unit
1818 H Street NW
Washington, D.C. 20433, U.S.A.
Tel: (202) 458-1876
Fax: (202) 522-3573
Email: cbennett2@worldbank.org
Website: www.worldbank.org

A publication of the World Bank East-Asia Transport Unit
sponsored by the Transport and Rural Infrastructure Services
Partnership (TRISP). The TRISP-DFID/World Bank Partnership has
been established for learning and sharing knowledge.

This specification is a product of the staff of the World Bank
assisted by independent consultants. The findings, interpretations,
and conclusions expressed herein do not necessarily reflect the
views of the Board of Executive Directors of the World Bank or the
governments they represent.

The World Bank does not guarantee the accuracy of the data
included in this work. The boundaries, colors, denominations, and
other information shown on any map in this work do not imply any
judgment on the part of the World Bank concerning the legal
status of any territory or the endorsement or acceptance of such
boundaries.

Quality Assurance Statement
Report Name: Prepared by:
Pavement Condition Data D. Brown and T. Thomsen
Collection System Generic Reviewed by:
Specification W. Herr, P. Hunber, R. Fox-Ivey, B.
Jan, K. Wang
Project Manager: Approved for issue by:
C. Bennett C. Bennett
Cbennett2@worldbank.org
9 January 2007

Revision Schedule
Rev. Prepared Reviewed Approved
Date Description
No by by by
Updated to make consistent with other
1.1 1/9/07 specifications and to incorporate CRB DB CRB
additional reviewer comments.

Generic Equipment Specifications for Road Data Collection Equipment

INTRODUCTION

This document presents a generic equipment specification to be used for the procurement of
vehicle mounted road survey equipment. It details the requirements for equipment designed
to measure pavement roughness, rutting, texture, skid resistance, road geometry, crack
detection using video logging, and right-of-way (ROW) video. Not all systems will collect all
these data items, so the specification is designed to only have clauses included reflecting the
data the Agency requires.

It is intended that data collected will be used for pavement management and should meet or
exceed the specific requirements as detailed in Information Quality Level Two (IQL2) 1 . IQL2
provides a level of detail sufficient for comprehensive programming models, for standard
design methods, and to distinguish the performance and economic returns of different
technical options with practical differences in dimensions or materials. It calls for automated
acquisition methods for network surveys. The automated equipment must be capable of
surveying a minimum of 10,000 km per year, surveyed over a three to four month period.

This generic specification can be used by any Agency as a basis for developing a detailed set
of equipment specifications that meet their particular network or survey requirements. The
user may select all equipment types and/or options, or only those deemed necessary for the
particular network or Agency.

This generic specification contains the minimum equipment specifications required to achieve
the level of accuracy and repeatability for the user to have the necessary confidence in the
data collected to facilitate the ongoing analysis for network maintenance and upgrading. It
builds on the experience of the World Bank on a number of different projects to help facilitate
sustainable data collection. It was developed with feedback from a number of consultants and
equipment vendors.

Accompanying notes provide additional background information, discussion, and typical
solutions that may assist the Agency in preparing the detailed specification for procurement.
The Agency may decide to include some of these notes in an actual specification. However it is
generally considered better to let the Supplier elaborate on their understanding and approach
in the bid, and to suggest alternative solutions, rather than to be too proscriptive in the
specification on the actual solution, approach or methodology.

This generic specification does not include details of the Database/Road Management System
(RMS) or end use for the collected data. The Agency will therefore need to be aware of data
format, data reporting intervals, and requirements for data that a particular RMS may require
when specifying a particular equipment type2. If the Agency does not have an RMS, the World
Bank has developed a generic Terms of Reference for the Supply and Installation of an RMS
which can be downloaded from www.road-management.info or
www.worldbank.org/transport.

Prior to any procurement, it is important that the Agency has an understanding of their needs
as well as what technologies are available. The Agency should review the report “Data
Collection Technologies for Road Management” which describes the different types of available
technologies and how to select the most appropriate technology for a given situation. The site
1
See ‘Guidelines on Calibration and Adaptation of HDM-4’ for a description of the IQL concept.
Available for download from www.road-management.info.
2
See McPherson and Bennett (2005): ‘Success Factors for Road Management Systems’ for a
discussion on RMS and their data requirements. Available for download from www.road-
management.info.

Version 1.1 - 9 January 2007 i


www.road-management.info contains the contact details for some vendors, as well as
brochures and equipment specifications.

Comments and suggestions on this document should be sent to:

Christopher R. Bennett
The World Bank
1818 H Street NW
Washington, D.C. 20046
+1-202-473-0057
cbennett2@worldbank.org

Updates will be posted to www.road-management.info as well as the World Bank’s transport
web site www.worldbank.org/transport.

Version 1.1 - 9 January 2007 ii


Notes on the Format

1.1 Section / Clause Heading Yes
Text in boxes with blue shading is intended for client staff preparing the
Specification. It includes background explanation on the purpose of the
clause, and additional discussion as appropriate.

Text in gray boxes indicates actual text that may be included in a Specification.

<Text included in italics provides optional selection depending on client
requirements. Select the appropriate option>

White boxes are spaces for Client notes while planning the Equipment Specification

Terminology
Agency The agency procuring the equipment
RMS Road Management System
Supplier The supplier providing the equipment

Version 1.1 - 9 January 2007 iii


Table of Contents

INTRODUCTION........................................................................................................i
1 OBJECTIVES...........................................................................................................1
1.1 Objectives of the Client.....................................................................................1
1.2 Summary of Equipment Needs...........................................................................1
1.3 Procurement Process.........................................................................................2
2 COMMON EQUIPMENT SPECIFICATIONS....................................................................4
2.1 General Survey Conditions.................................................................................4
2.2 Survey Computer and Operating System............................................................5
2.3 Data Processing................................................................................................5
2.4 Survey Vehicle ................................................................................................6
2.5 Data Display....................................................................................................7
2.6 Storage Device – Data Backup...........................................................................7
2.7 GPS................................................................................................................8
2.8 Location Markers..............................................................................................8
2.9 General Equipment Specifications.......................................................................9
2.10 Data to be Recorded and Stored.......................................................................9
2.11 Data Format.................................................................................................10
3 EQUIPMENT SPECIFICATIONS................................................................................12
3.1 Roughness – Laser Profilometer........................................................................12
3.2 Roughness – Response Type Roughness............................................................14
3.3 Rutting..........................................................................................................15
3.4 Texture.........................................................................................................17
3.5 Skid Resistance..............................................................................................18
3.6 Road Geometry..............................................................................................19
3.7 Crack Detection..............................................................................................21
3.8 Right of Way Video.........................................................................................22
4 EQUIPMENT VALIDATION.......................................................................................24
4.1 Calibration and Validation – General..................................................................24
4.2 Calibration and Validation – Methodology...........................................................25
4.3 Roughness.....................................................................................................26
4.4 Rutting..........................................................................................................27
4.5 Texture.........................................................................................................28
4.6 Skid Resistance..............................................................................................29
4.7 Road Geometry..............................................................................................29
4.8 Crack Detection..............................................................................................31
4.9 Right of Way Video.........................................................................................31
4.10 100 km Field Validation..................................................................................31
4.11 Acceptance Certificate...................................................................................31
5 EQUIPMENT TRAINING, WARRANTY AND ONGOING SUPPORT....................................33
5.1 Warranty and Ongoing Support........................................................................33
5.2 Training.........................................................................................................33

Version 1.1 - 9 January 2007 iv


1 OBJECTIVES

1.1 Objectives of the Client Yes
Common objectives of clients purchasing road-monitoring equipment are
listed below.

 Implementing efficient data collection processes that provide the
required data to the specified accuracy.

 Establishing well-defined responsibilities for all aspects of road data
collection and data management

 Facilitate the justification for budget, and help direct limited funds
towards those areas where the return on investment will be
greatest.

 Develop a road survey team within a wider asset management
group who can successfully collect pavement condition data for use
in a Road Management System

The equipment will provide a means for the collection of accurate pavement
condition data which will assist the Client in defining the true condition of the road
network. The equipment will be used to:

 Provide network condition data to facilitate year on year comparisons and
to define and track changes in the network condition.

 <Include others as appropriate>

1.2 Summary of Equipment Needs Yes
The equipment types selected by the highway agency must be determined
before the specification is prepared. The paper “Data Collection
Technologies for Road Management”3 published by the World Bank
provides details on the types of data used for road management and the
different technologies available to collect the data. The issues discussed in
this report should be fully understood before developing the procurement
specification. Questions which should be utmost in the mind when
preparing an equipment specification are:

 What is the end use for the data

 What type of network is being measured

 Is the equipment selected applicable to this network

 What do we need to measure

3
Available for download from www.road-management.info.

Version 1.1 - 9 January 2007 1


Among the factors that should be considered are:

 Where the network is very rough or is unsealed then laser
technology for measuring roughness is not appropriate.

 Where a network is primarily concrete and is less susceptible to
rutting, do you need to measure transverse profile?

 Where the network is small has low volume traffic and the
maximum speed on the network is 50km/h is there a need to
measure skid resistance?

From the following list, include only those equipment types deemed
necessary for your particular network.

One (1) <define appropriate number> set of equipment for the measurement of the
following pavement condition data is required:

 Roughness derived from the Longitudinal Profile <delete if not required>

 Roughness using response-type instrument <delete if not required>

 Rut Depth derived from Transverse Profile <delete if not required>

 Texture as Mean Profile Depth <delete if not required>

 Skid Resistance <delete if not required>

 Road Geometry <delete if not required>

 Right of Way (ROW) video <delete if not required>

 Crack Detection – Video Logging <delete if not required>

1.3 Procurement Process Yes
This specification calls for the procurement only to be completed after the
system has been validated (see Section 4). Validation is essential as it
ensures that the supplier’s equipment fully conforms to the client’s
specification. Unfortunately, this has not always proved to be the case. The
validation also confirms that the equipment can measure the required
parameters on the network and under the conditions where it is intended.

The procurement process shall be as follows:

 The bids shall be opened and reviewed in accordance with the bid
evaluation process and a notification of award shall be issued.

 The supplier shall supply the equipment as per the terms of the contract of
supply.



 Upon receipt of equipment a validation study shall be undertaken to confirm
that the equipment meets this specification.

 As part of the validation study, 100 km of surveys shall be conducted to
confirm that the data can be processed and entered into the client’s
system.

 An acceptance certificate for the equipment shall only be issued after
successfully completing the validation study.



2 COMMON EQUIPMENT SPECIFICATIONS
When measuring a number of different pavement condition parameters there are equipment and
operational specifications common to all measurement equipment. These common specifications are
grouped together here.

2.1 General Survey Conditions Yes
This is where a detailed description of the network to be surveyed should
be included. This should list all factors that might influence the survey
equipment. For example if the network is residential, or has significant
volumes of slow moving traffic (horse drawn carts) then the minimum
survey speed may be a consideration. The length of the network should be
broken down by surface type and/or road classification.

The equipment must be of a robust design capable of operating under the expected
local conditions by local survey technicians trained in its operation.

Data collection activities should be restricted when the road surface is wet,
contaminated with debris or when the temperature is outside the specified limits.

The following is the distribution of the road network by pavement type: <modify to
suit>

 Bituminous 10,000 km <modify to suit>
 Portland Cement Concrete 3,000 km <modify to suit>
 Unpaved Roads 22,000 km <modify to suit>
 TOTAL 35,000 km <modify to suit>

In terms of road classes, the following is the distribution of the network: <modify
to suit>

 Urban 7,000 km <modify to suit>
 Expressway 3,000 km <modify to suit>
 Rural – Paved 3,000 km <modify to suit>
 Rural - Unpaved 22,000 km <modify to suit>

All survey equipment should be specifically designed for operation at normal local
highway speed on both Urban/rural roads and expressways/highways included in
the network, and be capable of measuring on both bituminous and concrete
pavements where the predominant pavement type will be bituminous roads.
<modify to suit>

<Provide a general description of the network terrain.>



 For rural and urban roadway applications, the minimum valid operation
speed is 25km/h unless a lower speed specified by the equipment
manufacturer meets the validation criteria.

 Repeatability and accuracy at the minimum speed will be confirmed during
qualification verification.

 Maximum vehicle acceleration/deceleration limited to 2m/s2 or flagged in
the reported data when these limits are exceeded.

 Vehicle speed outside the specified limits should be flagged in the reported
data.

 A minimum start-up and termination length of 50m is required. The start-
up length data should be excluded from the reported data.

 The ability to Flag recorded data and record specific road furniture
and pavement inventory which may affect or influence the data
collected.

2.2 Survey Computer and Operating System Yes
Computer and operating software continue to rapidly develop and change.
Therefore it is prudent to ensure the survey equipment has as long a
service life as possible by ensuring that current software and hardware are
used and that backup/support will be maintained.
For example until 2003 data acquisition systems operating only under
Windows 98 were common-place, but by 2006 this operating system was
no longer supported by leading computer manufacturers. This creates a
risk to the Agency in the event of hardware failure. The operating system
must therefore be currently supported by its supplier and provide the full
functionality for operating the equipment. Typically, this means that it is
one which has been released or updated in the last 2-3 years.

 The survey computer should use an operating system currently supported
by the industry.

 The computer should be equipped with a storage drive capable of storing
the network survey data covering a 30 day period <modify to suit>.

2.3 Data Processing Yes
Many equipment suppliers license the software used to collect and process
data, and charge excessively for additional copies, so it is advisable to
determine in advance the number of copies likely to be required when
reviewing system requirements.
The key issue is the number of concurrent users. Agencies tend to think in
terms of the total number of people who might eventually make use of the
software. On the other hand, some software packages are licensed up to a
maximum number of “concurrent users”, meaning the maximum number of
people who can access the system at the same time. It is often difficult for
an Agency to estimate the number of concurrent user licenses they need. A
rule of thumb is that the number of concurrent users would be at most
around 20 - 30% of the total users. Additional licenses can always be



purchased at a later date if required so it is better to estimate at the lower
end of the number of users.
Future ongoing maintenance and support fees need to be clearly identified.
During the procurement. Typically, these can be some 10-20% of the
software cost, on an annual basis.

 The supplier shall provide a complete library of data collection and
processing software with the equipment as a back-up in the event that
there is a need for re-installation.

 The equipment will be supplied with a minimum of three (3) <specify
requirements> licenses to operate all data collection and or processing
software for a period of five (5) <specify requirements> years without
additional fees.

2.4 Survey Vehicle Yes
This clause is only required if the equipment is to be procured either
installed in a vehicle or if a vehicle is to be procured at the same time.
It is necessary to ensure that the survey vehicle is appropriate for your
network:

 Where possible, ensure that locally manufactured vehicles are used
for the platform. These vehicles will be easier to service and have
spare parts readily available.

 Where an imported vehicle is recommended by the equipment
supplier, ensure that there are no import restrictions, parts are
readily available, and that the vehicle can be serviced locally
throughout the entire country, not just In major centers.

 Ensure that the fuel type is also appropriate. For example, there is
no use having a petrol vehicle if petrol is more expensive and only
available at the major centers.

 The vehicle should be large enough to accommodate all the required
equipment without major structural modifications, including a water tank
of sufficient capacity to survey at least 200km where skid resistance is to
be measured.

 The engine, steering mechanism, and suspension components should be
adequate to allow smooth maintenance of speed and direction of travel.

 The interior temperature and humidity of the vehicle should be maintained
within the tolerable limits of the instrumentation and operators.

 The vehicle should be Right/Left <delete as appropriate> hand drive.

 Have an automatic transmission

 Have cruise control <delete if not desired>

 Have a petrol/diesel <delete as appropriate> engine



 The engine shall have a minimum displacement of 2.5 L <change as
applicable> and minimum power of 85 kW <change as applicable> to
allow the vehicle to survey at a maximum speed of 100 km/h

 Have a drive train operating on 4 x 4/4 x 2 <delete as appropriate>

 Be designed so that the operator is not exposed to noise levels above 85
dBA

 Shall comply with <specify country> national emission exhaust standards

 Shall comply with <specify country> national vehicle crash safety
standards

2.5 Data Display Yes
Displaying the condition data in real time while it is being collected aids
quality control. The surveyor/operator will over time be able to view the
data and confirm that it is a good reflection of the actual pavement
conditions.
Furthermore, when faults or equipment failures occur a visual display of
the data will aid detection of the fault, thus ensuring that the network
survey is stopped as soon as possible.

 Some form of data display is required that allows visual monitoring of the
system outputs in real time to ensure data is being collected and that the
system is operating correctly

 The computer screen should as a minimum display all processed outputs
as a function of distance, along with recorded events.

A graphical display is preferred as it is easier to see and interpret in a
moving vehicle.

2.6 Storage Device – Data Backup Yes
Retaining all raw data so that post processing/reprocessing can be
undertaken if required, necessitates large storage capacity—especially
when video is being captured. Furthermore, regular backup to enforce
data checking and thus avoid data loss due to equipment failure should be
part of the normal Quality Assurance (QA) procedures developed by the
survey team. Therefore it is essential to have a fast robust independent
backup medium for all data.

 A DVD-RW/USB Drive/IEEE 1392 Firewire Drive <delete what is not
appropriate> storage device shall be provided for the recording and long-
term storage of raw data and processed data.

 The system shall have the capability for uploading data to an intranet



Data backup and quality control (QC) checking is paramount in surveying.
Extra redundancy, for example by using multiple hard drives which
simultaneously record the data in this area can be invaluable. This can
also provide a means for independent QC of the data in the office.

2.7 GPS Yes
Location referencing is a problem experienced in almost all network
surveys. Texture, roughness, curvature, terrain and operator variability all
influence the measured distance. GPS coordinates linked directly to the
data can assist to minimize these effects. Since the marginal cost of GPS
data collection is low, it is recommended that all systems have GPS data
collection. Horizontal resolution is of primary importance so only it is
specified.

 The equipment shall include GPS data capture, collected simultaneously
and linked to all other pavement condition and inventory data collected.

 The GPS measurements shall have a corrected/uncorrected horizontal
accuracy of 1m/3m/other <specify as appropriate> Note 95% of the
readings should achieve the specified accuracy.

 This shall be achieved by having the data uncorrected/differentially
corrected using post-processing/corrected in real-time using
RTCM/corrected in real-time using NAVCOM Starfire/corrected in real-time
using Omnistar/other <specify as appropriate>

In specifying GPS accuracy it needs to be recognized that there is a
cost/performance trade-off. Uncorrected GPS will typically have +/- 3.3 m
accuracy 95% of the time, while differentially corrected will be much
more accurate.

2.8 Location Markers Yes
All networks are defined through a series of Location Reference Points.
These points define where particular events or road furniture are, and
therefore need to be defined very accurately during the surveys.

 Section start, intermediate feature location(s), and section end, identified
by location marks shall be accurately recorded either by surveyor/user
input or by an automated means, such as a magnetic or optical detection
process.

 The equipment must have a means to record event location data within
the data records.

 The data collection software must accommodate location-referencing
identification, and distance reset. To minimize location referencing
measurement errors, the data acquisition system must allow for the
segment survey distance to be reset to 0 at Network Reference Locations,
while retaining the cumulative distance traveled.



2.9 General Equipment Specifications Yes
Other items not included specifically above. Note if there are items which
are specific to the network and are required for all selected condition
parameters then these should be included here. For example specific road
inventory items.

 The distance measurement instrument (DMI) shall be capable of
longitudinal measurements within 0.1% of true distance.

 The system shall have an operating temperature range of 0-50 degrees C

 The roughness, texture and skid resistance sensors shall be spaced at an
interval of <Select the appropriate spacing from Table 1 below>

The sensor spacing is selected to maintain consistency between measuring
systems. The survey vehicle measures roughness, texture and skid
resistance at the location where the vehicle tire/roadway interface for the
majority of the network fleet occurs. Typical values are 1.65m or in the
range 1.3m to 1.8m. Where the network vehicle fleet is heavily biased
toward a particular vehicle type then a different spacing may be more
appropriate. Table 1 details the approximate wheel spacing for different
vehicle types.

Table 1: Vehicle Wheel Path Measurements
Vehicle Class Approximate Wheel Spacing (m)
Sub Compact Car 1.30 – 1.40
Mid Size Car 1.40 – 1.50
Full Size Car 1.50 – 1.60
Mid Size Pickup or Van 1.50 – 1.65
Large Pickup or Van 1.65 – 1.80
Light Truck 1.70 – 1.80
Heavy Truck 1.80 – 1.85

2.10 Data to be Recorded and Stored Yes
The following items must be recorded with or linked to each of the specific
condition data items detailed in the equipment specific requirements
detailed below.

 Date and time of day

 GPS co-ordinates (X, Y, Z) <delete if GPS data not collected>



 Location reference and description of section

 Vehicle ID, Crew ID

 Weather conditions

 Surface description

 Run number

 Measuring speed and instantaneous acceleration/deceleration

 Direction of survey relative to reference direction (increasing/decreasing)

 Lane number or transverse position on road

 The following road furniture items <specify as required>
• Number of Lanes
• Pavement Type
• Shoulder Type
• Pavement Width
• Shoulder Width
• Visual Condition Rating
• Etc.

2.11 Data Format Yes
The particular requirements for each road management system (RMS) can
be quite different and therefore it is best to specify a particular data
format so that the data from the equipment are compatible with the
Agency’s system. There may also be some accumulated result or specific
statistical results that are peculiar to the RMS requirements (e.g. data
averaged per 100 m) and this is where these items can be defined.
If possible, the specification should include precise details on the RMS or
database that will be used to store the data. The more information
provided, the easier it will be for the supplier to ensure that they can
successfully interface with the RMS. The Agency must also recognize that,
depending on the RMS in use, it may be necessary for the RMS supplier to
modify or update their system to make use of the data from the equipment.
It is not always practical for the equipment vendor to tailor their system to
every RMS.
if the Agency does not have an existing RMS it is useful for the
specification to include the provision of, as a minimum, a simple database
program for storing and using the data. Should the Agency be interested in
a full RMS, reference should be made to the generic Terms of Reference for
the Supply and Installation of a Road Management System available for
download from www.road-management.info.



 Data should conform to <specify any particular requirements for data>.

 The equipment shall be able to produce export files in an industry standard
format (e.g. comma separated values) so that the files can be read by other
applications such as spreadsheet programs.

 The equipment shall be provided with data viewing software to allow the
Agency to review all data collected by the equipment in an integrated
manner. <Optional – may not be required if Agency is using its own RMS>

If the Agency has an existing RMS:

 The data will be stored in the Agency’s road management system (RMS).
This RMS is was supplied by <enter the vendor’s name and contact
details>. The current version of the software is <enter the version
number> and includes the following modules <enter the name of the
modules available>. The software is/is not <select which is appropriate>
under a current maintenance and support agreement with the software
vendor.

 Data should conform to <specify any particular requirements for data>.



3 EQUIPMENT SPECIFICATIONS

3.1 Roughness – Laser Profilometer Yes
These are the minimum requirements for vehicle mounted inertial profilers
designed to record the longitudinal profile using an accelerometer/laser
sensor combination to establish an inertial reference from which the
longitudinal profile is measured. Furthermore it establishes equipment
verification standards and procedures for the calculation of roughness in
accordance with the International Roughness Index (IRI) from the
measured profile.
The preferred measuring system will utilize a single accelerometer/laser
combination for each wheel path with both the accelerometer and laser
mounted directly above the wheel path measurement location. A single
inertial reference may be utilized provided the equipment can satisfy the
validation criteria detailed below.
Note a scanning laser is an acceptable alternative to the single wheel path
laser.

Measurement System:

 In addition to the specifications detailed below the equipment must also be
compatible with ASTM standard E950 (2004) ‘Standard Test Method for
Measuring the Longitudinal Profile of traveled Surfaces with an
Accelerometer Established Inertial Profiling Reference’,

 Number of measurement locations – two; one in each wheel path

 Note a scanning laser is an acceptable alternative provided it meets or
exceeds the accuracy and resolution specifications detailed for the single
wheel path laser and has a minimum scan rate of 25kHz.

Lasers

 Minimum No. of Sensors 2 - one in each wheel path
 Minimum Sampling Frequency 16 kHz
 Minimum Bandwidth 2 kHz
 Spot Size 0.2-5mm
 Minimum Resolution 0.2mm
 Accuracy ± 0.5mm
 Measuring Range ± 100mm
 Stand Off ≥300mm

Accelerometers

 No of Sensors 2 - one with each laser;
 Minimum Measuring Range ±2G
 Minimum Resolution 10µG
 Minimum Bandwidth DC -300Hz



For pavements with speed humps and/or other large pavement
irregularities a standoff greater than 300mm may be required.
For roads with average roughness IRI > 5m/km a minimum measuring
range of ±3G will be required.

Profile Sampling and Recording Intervals:

 Longitudinal Profile should be spatially sampled i.e. measured at a constant
distance interval along the road

 Maximum profile sampling interval - 5mm (the largest distance between
successive profile samples)

 Maximum recorded interval - 100mm, (the largest distance between
successive profile heights permanently stored by the survey computer.

 Base length for the IRI moving average filter - 125mm or less.

Data to be Recorded and Stored:

The profile data collection should record data on the following items:

 Profile data for both left and right wheel paths

 Wheel path and Lane IRI accumulated at 10m, 20m, 50m, and 100m
intervals. <select as appropriate>4 Note: the lane IRI is calculated as the
average of the left and right wheel path.

Effects of Pavement Distress and Surface Texture:

Pavement surface properties such as alligator cracking and texture can have a large
influence on transverse variability. This can result in difference between the
maximum and minimum IRI values from 0.2 to 0.5m/km therefore the data
collection system must have the ability to identify sections where extensive
cracking and changes in texture occur.

 Transverse cracking - data must be flagged manually where serious
cracking occurs.

 Surface type and texture affect the measurement repeatability of the profile
and roughness. Accordingly all equipment must demonstrate measurement
accuracy and repeatability on a range of surfaces through a validation
exercise. The accuracy and repeatability of the 100m IRI data for five
individual runs must not exceed the mean of the runs by more than the
following limits:

Asphalt Concrete 2.0%
Fine grade chip seal 2.0% ± 0.05m/km
Coarse grade chip seal 2.0% ± 0.1m/km

4
The reported roughness interval will in part be determined by the requirements of the Road
Management System using the data.



3.2 Roughness – Response Type Roughness Yes
These are the minimum requirements for the use of response-type
roughness meters. This consists of a mechanical or accelerometer based
instrument which measures the response of the vehicle chassis or axle to
the road. The data are then processed to establish the IRI, often via a
calibration equation.
The preferred measuring system will measure roughness in each wheel
path using two sensors. A single measurement location (one wheel path or
the centre of the axle) may be utilized provided the equipment can satisfy
the validation criteria detailed below.
Note: Specifications for the two most common systems are detailed below,
however, alternative systems may be included as long as they meet the
validation criterion detailed in Chapter 4.

Motion Encoder Bump Integrator Type Systems: (e.g., CSIR LDI, ROMDAS BI,
TRL BI)

 No of Wheel paths 2/1 <select as required>

 Minimum Measuring Range 0.8mm

 Resolution 1.0mm

Accelerometer Type Systems: (e.g., AL-Engineering Roadman, ARRB
Roughometer)

 No of Wheel paths 2/1 <select as required>

 Minimum Measuring Range +2G

 Resolution 10mG

 Minimum Bandwidth DC - 100Hz


 The raw response data for both left and right wheel paths accumulated at
10m, 20m, 50m, and 100m intervals. <select as appropriate>

 Wheel path and Lane IRI accumulated at 10m, 20m, 50m, and 100m
intervals. <select as appropriate> Note: the lane IRI is the average of the
left and right wheel path.



3.3 Rutting Yes
These are the minimum requirements for vehicle-mounted equipment
designed to measure the pavement transverse profile. Three possible
systems are considered, these are:

 A single or multiple scanning laser system which measures the full
transverse profile

 A multi laser or ultrasonic sensor system complete with inertial
platform to measure discrete distances from the road surface to the
inertial platform across the traveled lane.

 A multi laser or ultrasonic sensor system to measure discrete
distances from a rut bar to the pavement surface across the
traveled lane.

As described in the report ‘Data Collection Technologies for Road
Management’, the accuracy of rutting is dependant on the number
of sensor sampling points across the road and the longitudinal
sampling. Due to the large variations in cost between different rut
depth devices, it is recommended that users consider all three types
of systems above. As long as they meet the validation requirements
the data will be acceptable.

The number of measurements per profile is the minimum that will
give appropriate results and the optimal spacing of sensors varies
depending on the number5. The more measurements the more
accurate the results, although there is a decrease in the accuracy
with increasing measurements above around 206.

Measurement System:

 Minimum Spot Size (lasers only) 0.2-5mm



 Minimum Measuring Range ± 100mm


 Minimum number of measurements/profile 13*

 Minimum measurement width: 3200mm *

 Maximum distance between sensors 200 - 400mm*

* The transverse profile is measured to determine the extent (both width and
depth) of wheel path rutting. The maximum distance between measurements is
5
See “Harmonising Automated Rut Depth Measurements” available from
www.ltsa.govt.nz/research/reports/277.pdf for a discussion on sensor spacing and numbers.



200mm where there is a significant vertical rut transition point i.e. outside/inside
edge and middle of the rut, elsewhere the maximum distance is 400mm.

For pavements with speed humps and/or other large pavement
irregularities a standoff greater than 300mm may be required.
As the rutting extent is dependent on both the lane width and the network
vehicle fleet, the number and spacing of sensors can only be fully defined
once the network requirements are established.


 Maximum profile sampling interval - 5m, (the smallest distance between
successive profile samples)

 Maximum recorded interval - 5m, (the smallest distance between
successive profile heights permanently stored by the survey computer)

Data Collection Speed Restrictions:

 Repeatability and accuracy at the minimum speed should be confirmed
during validation.

Calculation of Rut Depth:

 The left and right wheel path rut depths calculated as the rut depth under a
1.2m/2m/3m straight-edge <select as appropriate> or under a string line.
<or other user defined method>


The profile data collection should record data on the following items:

 Raw Transverse Profile Data

 Left and right wheel path Rut Depth and Rut Width under a 2m straight
edge reported at 10m, 20m, 50m, and 100m <select as appropriate – see
roughness >

 Other system specific measurement options

Inertial Sensors - Accelerometers/Gyroscopes <only applicable for
inertial platforms>

 Minimum Number of Sensors - 1

 Minimum Measuring Range +2G

 Minimum Resolution 10µG

 Minimum Bandwidth DC -300Hz.

Note for roads with roughness >5IRI a minimum measuring range of +3G may be
required.



A straight-edge simulation is the standard rut depth calculation
methodology, if a different method is used locally to calculate rut depth
then it should be clearly defined.

3.4 Texture Yes
This specification is intended to provide the minimum requirements for
vehicle mounted laser profilers designed to record the pavement texture.
Furthermore it establishes equipment verification standards and
procedures for the calculation of Mean Profile Depth (MPD) and/or RMS
Texture from the measured texture profile.
Measurement System:

Equipment must be compatible with ASTM standard ‘E1845-01 Standard Practice
for Calculating Pavement Macrotexture Mean Profile Depth’

Lasers

 Minimum No. of Sensors 2 - one in each wheel path6

 Minimum Sampling Frequency 32 KHz

 Minimum Bandwidth 10kHz

 Minimum Spot Size 0.45mm



 Measuring Range ≥ ± 100mm



 Texture Profile should be sampled at constant distance intervals along the
road

 Maximum profile sampling interval – 1.0mm. i.e. The largest distance
between successive profile samples7.


The texture data collection equipment should record the following data items:

 Raw texture data in both left and right wheel paths8 <optional>

 Wheel path texture as MPD and RMS data measured/accumulated at 10m,

6
Note to minimize costs and or ensure compatibility with other measuring equipment a single texture
laser may be specified.
7
See ISO 13473 and ASTM E950.
8
The recording of raw texture data will result in a significant volume of data. The need for this should
be carefully assessed.



20m, 50m, and 100m intervals <select as appropriate – see roughness>

3.5 Skid Resistance Yes
Friction is defined as the resistance to relative motion between two bodies
in contact, while Skid Resistance is defined as the property of the
trafficked surface that develops friction between a moving tire and the
pavement surface. Skid resistance can be considered as a characteristic of
friction. The devices can collect data at user defined intervals or in
continuous fashion.
Physical properties that affect the measured skid resistance are:

 Pavement temperature

 Slip speed and slip angle

 Surface texture

 Film thickness of the water applied to the pavement surface

 Contact area and tread pattern of the measuring wheel.

This dependence is directly related to the specific device used to measure
skid resistance, therefore the validation exercise will need to incorporate
specific measurements to demonstrate that any correction applied to
compensate for changes resulting from these affects are correctly applied.

Pavement temperature is not required to be recorded with all systems.

The measuring systems can measure either yawed (at an angle to the direction of
travel) or in line skid resistance. The Devices can record the skid resistance using a
locked wheel, or at different slip speeds. However in all cases the measuring device
must have a traceable path to the Skid Resistance Index as defined in the European
Committee for Standardization Technical Committee CEN227 in report
prEN13036-2, or an equivalent index, which is independent of the device.

Measurement System:

Skid Resistance is recorded simultaneously with pavement texture and road
geometry to enable the International Friction Index (IFI) to be calculated and
investigation levels applied as required.

 Sample Interval 20m

 Resolution 0.1% of scale appropriate to device

 Load Cell Bandwidth 0 - 1kHz

 Thermometer Accuracy 0.5°C

 Repeatability Refer to validation criteria



 Survey Speed Dependence: to be defined by equipment manufacturer and
confirmed in validation exercise.

 Pavement Temperature Correction: to be defined by equipment
manufacturer and confirmed in validation exercise.

 Skid Resistance Recording Interval: the smallest distance between
successive data permanently stored by the survey computer should not be
greater than 50m.

 The data acquisition system will accommodate the input of investigatory
levels where road geometry (curvature and grade) and furniture require
different levels of skid resistance.

 Data Collection Speed Restrictions: Survey equipment should be operated
at the speed that maintains the optimum slip ratio for the specified
equipment type, as defined by the manufacturer.


The data collection system should record the following items:

 Raw friction data and processed skid resistance for each wheel path tested

 SP and IFI for each wheel path and lane in two wheel paths tested

 Investigatory levels as required

 A rolling average is used to report data at 100m intervals

3.6 Road Geometry Yes
The horizontal curvature and vertical grade should be considered an
optional item for standard centerline surveys. Significant cost savings can
be realized by having the curvature and grade extracted from the GPS data

If very accurate curvature and grade data are required, the data should be
collected utilizing an accelerometer/gyro combination. Data can be
corrected through post processing or directly recorded with differential
correction provided in real time. For a vehicle traveling at 75km/h a
sample rate of 10Hz will provide coordinate data every 1m.

Road Centerline:

The road centerline is a nominal line representing the middle of the road or
carriageway on multi-lane roads. It will be measured using a GPS Receiver
configured to provide either uncorrected GPS or DGPS in real time.

 Positional Accuracy (Corrected/uncorrected) <1.0m/3.0 <select>

 Sample Interval 0.1S (10Hz)



 Tracking 12 Channel L1/CA code

 System Outputs NMEA-0183 or equivalent

 Initialization Time <20 Sec

 WGS84 coordinate standard data or as specified

Offset of the coordinate data should ensure that the centerline (between increasing
and decreasing lanes) is reported.

Horizontal Curvature and Vertical Grade: <delete if using accelerometer/gyro
systems>

The GPS data will be analyzed to determine the horizontal curvature and
the vertical gradient. The curvature in meters and gradient values in
degrees will be given for 100 meter <define as appropriate> homogeneous
sections of the road.

Horizontal Curvature: <delete if to be calculated only from GPS data>

 Zero Offset (stationary) 0±0.1%FSD

 Accuracy 0.1Rad/km

 Angular Rate 50º/sec

 Resolution 0.05º/sec

 Bias < ± 20º/hr

Vertical Grade: <delete if to be calculated only from GPS data>

 Range (minimum) ±2g

 Resolution Range (minimum) 100ug

 Frequency Response 0-100Hz


The road geometry data collection system should record the following items:

 Raw Road Geometry Data

 Road Centerline, Vertical Grade, and Horizontal Curvature reported at 10m
<if using accelerometer/gyro combination> 100 m <if interpolating from
GPS data> intervals.



3.7 Crack Detection Yes
Crack detection is not a standard item on equipment systems and is still an
evolving technology. Some automated crack detection software is available
but would need to be proven on a particular network and pavement type
before it is adopted. Most current practice is to video the pavement using a
high-speed high-resolution camera mounted on a boom attached to the
survey vehicle such that the pavement surface detail is recorded along
with location referencing information. The recording method can be based
on area scanning or, more recently, line scanning.
Crack identification and recording can be undertaken in real-time during
the survey by analyzing the images as they are collected, or as a post-
survey activity using the captured image data. For post-processing one of
two methods is used:

 The reviewer manually views the images and uses software to
record the various pavement distress types through keyed/mouse
entry onto a computer; or
 Software automatically recognizes and detects cracks, often with
manual assistance.

Due to the evolving nature of crack detection hardware and software,
these crack detection specifications are limited to specifying the resolution
of the camera system.

Minimum Equipment Requirements:

Camera

 Image Position Error 1m

 Camera Type area or line camera

 Number of cameras 1 or 2

 Color 8-bit gray scale

 Minimum Resolution 2mm/pixel

 File Format JPEG, JPG, AVI, any industry
standard

 Minimum Coverage 100% - 3m wide

 Survey Speed 20 – 80km/hr

 Camera Enclosure IP 65

Review Software

Software will facilitate full condition rating of the video to produce an inventory of
pavement defects that can be integrated with other condition data.



3.8 Right of Way Video Yes
Right of way video is a useful network review tool and can be used to
resolve anomalies with location referencing etc. It can also be used to
record road inventory and road furniture information. The current practice
is generally to video the right-of-way pavement using a high-speed high
resolution camera mounted to the survey vehicle such that the forward or
driver view of the pavement is recorded along with location referencing
information.
The system should be specified with 1 – 3 cameras, If only the right-or-
way in front of the vehicle is desired, then a single camera system is
adequate. Additional cameras may be included to record to the side view
from the vehicle.
Due to the size of the files, it is recommended that images be sampled at
regular intervals, such as 10 m. This significantly reduces the size of the
images while providing sufficient data for road management purposes.

Minimum Equipment Requirements:

Camera

 Image Position Error 1m

 Camera Type IEEE –1394 Firewire or equivalent

 Picture Size 800 by 600 pixels9 <minimum>

 Color 24-bit Color

 Minimum Sampling Interval 5m at 80km/h <define>

 Frame Capture Rate Distance based

 File Format JPEG, JPG, AVI, any industry
standard

 Survey Speed 20 – 80km/hr

 Exposure range 1/10000 F1.4

The camera shall be mounted inside the vehicle/on the roof of the vehicle in a
waterproof enclosure <delete as appropriate>.

Overlay Software

Software will facilitate overlay of positional data including Distance, GPS, Road and
LRP ID. Video data must be integrated with other condition data.

9
This is the minimum resolution which meets the needs of many applications. Higher resolution up to
1280 x 960 pixels may be used for some applications, although this increases the cost of hardware
and storage requirements.



4 EQUIPMENT VALIDATION
The purpose of the equipment validation is confirm the proposed
methodology, the data collection, data processing, and reporting processes
meet the required standard, while maintaining consistency between
different data collection equipment. It also ensures that the data produced
by the equipment can be imported and used by the Agency’s RMS.

Validation also demonstrates that the equipment can operate under the
expected conditions of the network. Therefore in addition to meeting the
equipment specification detailed above, each equipment type must also meet
the validation requirements detailed below.
There are two issues addressed during the validation process—calibration
and validation:
 Calibration of the equipment confirms that measurements can
achieve a measurable/specified tolerance. Calibration does not
confirm that the equipment can measure the required parameter from
a moving vehicle. Data is filtered and processed to achieve the
desired output.

 Validation demonstrates that the survey equipment can be operated
by local surveyors on roads that are characteristic of their particular
network, and provide meaningful data of sufficient accuracy to meet
its intended use. Validation therefore confirms that the data capture,
associated filtering and data processing work on the client’s network.

An important part of the validation exercise is the field trial. Once the
equipment is calibrated and validated, it should be used to undertake
a minimum of 100 km of surveys. The data from these surveys should
be processed and entered into the Agency’s RMS. Depending upon the
design of the RMS, it may be necessary to modify either the RMS or to
have the equipment supplier produce a custom data format.

4.1 Calibration and Validation – General Yes
 Calibration by correlation with other vehicle mounted survey
equipment should not be used10.

 All measuring equipment must have calibration certification to an
international standard.

 Calibration certification will confirm individual equipment accuracy as
defined above for the measuring components of the system, the
accelerometers the lasers and the distance measuring system etc.

 Validation should be recognized as separate processes within the
overall objective of obtaining accurate and reproducible roadway
profilers.

 A validation program should be carried out prior to acceptance of the
equipment and /or before the start of data collection activities; this
must include operator validation.
10
The exception to this is when the equipment being validated is less accurate than the vehicle
mounted system it is being validated against. For example, a response-type roughness meter can be
validated against a laser profilometer.



 Continued measurement validation must be carried out during and at
the completion of data collection activities.

 A minimum of 6 sites, each 300m long, should be used for
roughness, and 5 sites each 200m long for both texture and rut
depth, selected to reflect the full range of operating conditions likely
to be encountered in the surveys.

4.2 Calibration and Validation – Methodology Yes

Validation Approach:
The survey equipment must be validated at each site against a reference
measurement. This is done by measuring sections of roads with the reference
instrument, and then the same sections with the survey equipment.

For roughness calibration the reference calibration equipment must be
compatible with ASTM standard E950 (2004) ‘Standard Test Method for
Measuring the Longitudinal Profile of Traveled Surfaces with an
Accelerometer Established Inertial Profiling Reference’, Class I.

The survey equipment must make at least five repeat runs over each of the
validation sections at 4 nominal speeds of 25, 50, 75, and 100km/hour or
within the limits specified by the manufacturer. The results must be
averaged to give the profile at each of the nominated speeds.

The line of best fit between the reference measurement and the survey
equipment using least squares regression is then established:

RM = SE x A + B

Where:
RM = The measurement from the reference equipment
SE = The measurement the survey equipment
A = slope of line of best fit
B = intercept of line of best fit (regression offset)

The equipment is considered validated when A and B, and R2 (the coefficient
of determination) are within the specified parameter ranges detailed in Table
2 below for all sites combined.

Repeatability – this is the expected standard deviation of measurements
obtained in repeat tests, using the same survey equipment on a single
randomly selected road. The standard deviation of measurement on each
segment must be within the tolerance defined for the different surface types
from the mean for each of the 5 repeat runs.

Assuming a normal distribution then the 95% confidence intervals for the
s
roughness is given by data ± t .
n



s
The error limit is defined by – β = t .
n

Where:
data = the data measured by the instrument (e.g. IRI m/
km, mm rut depth, etc.)
s = the standard deviation of the data in the same
measurement units
n = the number of runs
t = 2.776. This is the critical value for the t
Distribution for a Critical t Confidence Interval of 95%

 The equipment is considered to be repeatable when β is within the
specified percentage of the mean, refer Table 2 below11.

Table 2: Validation Limits
Parameter Slope Intercept Correlation Acceptance
(A) (B) R2 Limit β
Roughness 0.98–1.02 0.05IRI 0.99–1.00 < 0.030 IRI
Response Not 0.5IRI 0.93–1.00 < 0.30 IRI
Type Applicable
Roughness
Rutting 0.98–1.02 0.2mm 0.97–1.000 < 0.050 RD
Texture 0.98–1.02 0.05mm 0.98–1.00 < 0.030 MPD

4.3 Roughness Yes

Setting Reference Profile – The base road surface profile over the validation
sections must be measured using a reference Class 1 profiler. The reference
profiler is used to record the profile of each wheel path over the full validation
length. Each wheel path must be measured at least three times. The reference
profile must be taken as the average of the individual readings measured in each
wheel path.

Spectral Density - The ability of the survey equipment to measure the broad
range of wavelengths that constitute the road’s longitudinal profile can be
demonstrated through the equipment’s frequency response or transfer function
characteristics. It is therefore recommended that the spectral density be measured
and plotted along with the reference site spectral density measured. This is not
applicable for response type roughness measuring systems.

Interrupted Data Collection – interrupted data must be validated by:
 driving over the validation sections at varying speeds during each run and
achieving the same repeatability when compared to the constant speed run

 demonstrating the effects of stopping and starting and the effectiveness of
the equipment for handling survey interruptions (slow traffic etc.)

Autospectral density functions can be determined using the RoadRuf Public
11
These levels are designed for roads in good to fair condition (e.g., IRI<5m/km). If the roads are in
poor condition then the tolerances may be relaxed.



Domain Software. This software is available at the UMTRI Road Roughness User
Site at http://www.umich.edu/erd/roughness/

Examples of reference profilers are the ARRB TR Walking Profiler, the
Face Dipstick, the ROMDAS Z-250.
A comparison of the spectral density of the survey profiler and the
reference profiler is used to demonstrate that the profiler can measure
the range of wavelengths that constitute the road’s longitudinal profile.
Ideally the two should be identical.

4.4 Rutting Yes
The transverse profile and rutting validation process is undertaken on
sections that are representative of the network and covering the full
range of rutting expected on the survey network. The sections chosen
must as a minimum cover a range of rut depths in both left and right
wheel paths of 0 up to 40mm.
The validation of the reference profile is the preferred method of
validation, however, this either requires specialized equipment or is very
time consuming. Most validations are therefore done by measuring the rut
depth with a straight-edge and wedge and comparing the surveyed rut
depth with that from the measurement system.

Rut Depth - Is defined as the height between the pavement and a user defined
straight edge placed across the rut, i.e. the distance obtained from the manual
straight edge and wedge method.

Measurement Location – Profile and/or Rut Depth <select as appropriate>
measurements are taken at 5m intervals along each 200m section.

Using Reference Profiles

Setting Reference Profile – The reference transverse profile on each of the
validation sections must be measured using either a reference profile beam or
surveyor rod and level or other approved method. The method adopted must be
capable of measuring the transverse profile at 100mm intervals to a vertical
accuracy of ±0.25mm.

Reference Profile Validation - Transverse Profile graphs for both the reference
profile and the survey equipment for each speed must be provided to demonstrate
that the equipment is measuring the true pavement transverse profile.

Using Straight-Edge and Wedge

Establishing the Reference Rut Depth – The rut depth on each of the validation
sections is measured in both left and right wheel paths to an accuracy of ±0.5mm
at 5 m intervals along each 200 m section.

Rut Depth Validation – The survey equipment must be validated at each site



against the reference rut depth derived from the straight edge and wedge or,
where a reference profile beam is used, from the rut depth calculated from the
reference profile.

A visual review of the reference and survey profiler transverse profiles is
the easiest way to confirm that the survey profiler is able to define the
pavement transverse profile.

4.5 Texture Yes
The validation of texture depth is often impossible due to the absence of
available equipment for using in the validation process.
The texture validation process is undertaken on pavement sections that
are representative of the survey network. The range of Texture Depth
required for this validation should be determined from the characteristics
of the network. For example, surface treatment sections can have a range
of texture depth from 1mm to 4mm, while an asphalt surface may only
have a range of 0.5 to 2mm.

Setting Reference Profile:

The base road surface profile over the validation sections must be measured using
a reference texture device. Factors to be considered include:

 The reference device is used to record the texture profile in each wheel
path over the full validation length. The entire profile length in each wheel
path must be measured at least once.

 The ability of the survey equipment to measure the broad range of
wavelengths that constitute the road’s texture (0.5mm to 5m) can be
demonstrated through the equipment’s frequency response or transfer
function characteristics. It is therefore recommended that the spectral
density be measured and plotted along with the reference site spectral
density measured by the reference device.

 Autospectral density functions can be determined using the RoadRuf Public
Domain Software. This software is available at the UMTRI Road Roughness
User Site at http://www.umich.edu/erd/roughness/

 Texture Depth Validation: Texture Depth (MPD) is derived from the raw
texture profile as defined in ISO Standard 13473-1.

The survey equipment must be validated at each site against the reference texture
derived from the reference profiler.
Note where a reference device is not available the reference texture can be
measured using the manual Sand Patch Method. The texture depth is determined
by spreading a known volume of sand over the test site and measuring the area
covered. Refer ASTM Standard E965.



Examples of texture reference measuring devices are the Swedish Road
Traffic Research Institute (VTI) Stationary Laser Profiler selected as the
reference texture device for the PIARC experiment and the Transit NZ
Stationary Laser profiler or other equivalent reference devices.

4.6 Skid Resistance Yes
The validation of skid resistance is often impossible due to the absence of
available equipment for using in the validation process. The validation is
therefore limited to ensuring that the measurements are repeatable.

Calibration and validation will be undertaken in accordance with the European
Committee for Standardization Technical Committee CEN TC 227. Detailed in
report No. prEN 13036-2. The purpose of this calibration and validation is to
confirm that the measurement of skid resistance is independent of equipment
type.

The skid resistance validation process is undertaken on pavement sections that are
representative of the network to be surveyed, and cover the expected network
range of texture depth and skid resistance. Repeatability and bias will be
determined by driving the survey equipment in normal survey mode over five
calibration sites. A minimum of ten runs at each calibration site will be undertaken
over two days with five runs on each day. The skid resistance of the 20m values
will be averaged and the standard deviation calculated.

Operational speed dependence will be determined through a series of repeat runs
at three different speeds on at least two of the sites.

Validation will be confirmed when:

 The standard deviation for the 10 runs on any one section is less than 3%
of the mean of the ten runs.

 The speed characteristics are defined and repeatability is not compromised
by speed variation such that the above limits are not exceeded.

4.7 Road Geometry Yes

Road Centerline:

The road centerline should be validated both statically and dynamically.

 Static Validation: Static validation is determined by taking stationary
measurements at a location which has been accurately established by
registered surveyors, such as a local datum. A minimum of ten
measurements are taken and compared to the true location.

 Dynamic Validation: The survey equipment should be driven at normal
survey speed and survey mode, while recording road centerline coordinate



data through a loop section of not less than 5km containing at least five of
the ten reference locations. Coordinate data for each reference point
should be flagged as the vehicle passes the reference point and extracted
from the data stream. The loop runs should be made over two days at
different times.

The equipment operator must also demonstrate that the inertial system can
compensate for loss of GPS signal.

Validation will be confirmed when:

 All static measurements are within 0.5m of the true location

 All dynamic measurements are within 5m of the true location.

 The equipment must also demonstrate that loss of GPS signal does not
degrade data quality from that specified above.

 Repeat loop runs demonstrate that the spread of data is not greater than
5m at any one location within the loop.

Horizontal Curvature:

Validation sites will be selected as representative of the network to be surveyed,
and validation is undertaken by conducting a normal survey through the selected
sites containing curves of known radii. A minimum of ten sites with radii covering
the expected range of the network and/or the range from 50 to 300m should be
selected. Note both right and left hand curves should be selected.

Data from a minimum of five runs at each of three speeds covering the network
speed range or the equipment manufacturer specified range, at each test curve
should be collected, and the average curvature for each of the 10 curves reported.
A 30m moving average should be applied to the data and equipment should
demonstrate validation acceptance when the average of the five runs at each
section is within 5% of the actual curve radii, and the standard deviation of the
five repeat runs does not exceed 5% of the mean.

Vertical Grade:

Validation sites should be selected as representative of the network to be
surveyed, and validation is undertaken by driving the survey equipment over the
selected sites. A minimum of ten sites with grade covering the expected range of
the network and/or the range from zero to a grade of 10%.

Data from a minimum of five runs at each test site for three speeds applicable to
the network or the equipment manufacturer specified range should be collected,
and the average grade for each of the 10 sections reported. A 30m moving
average should be applied to the data and equipment will demonstrate validation
acceptance when the average of the five runs at each section is within 5% of the
actual grade, and the standard deviation of the five repeat runs does not exceed
5% of the mean. Note grade should be measured using a reference inclinometer or
through standard survey techniques.



4.8 Crack Detection No
No definitive method is readily available for validating this parameter.
Therefore it is recommended that the client review the system proposed
to see if it meets specific requirements.

4.9 Right of Way Video No
Right of way video has no definitive method for validation. Therefore it is
recommended that the client review the system proposed to see if it
meets specific requirements.

4.10 100 km Field Validation No
The final validation exercise consists of undertaking an actual survey on
at least 100 km of roads. This will ensure that the equipment is operating
correctly, that the operators are able to operate the equipment correctly,
and that the data can be used after the survey. It is only upon completion
of this 100 km field validation that the ‘Acceptance Certificate’ should be
issued.

Upon completion of the operator training, calibration and validation, each system
shall be used to execute 100 km of field surveys. These field surveys will cover the
full range of roads and operating conditions that the surveys will be undertaken
on. There will be urban/rural/paved/unpaved roads <selected as appropriate> in
the field validation. The field validation shall include the following:

 The equipment shall be operated in the same manner as when actual
surveys will be undertaken.

 The data from the equipment will be processed by the operators to
produce the outputs consistent with the requirements of this specification.

 The processed data shall be imported to the Agency’s RMS/viewed in the
supplier’s data view software/imported to a database <define as
appropriate based on Clause 2.11>. If the Supplier can show that their
equipment is exporting data in a open format which is consistent with
Clause 2.11 and that the problem with entering the data into the Agency’s
RMS is due to an RMS problem outside of the control of the Supplier (e.g.
cannot be resolved by simple reformatting of an export file) then the
Agency will accept that this requirement has been met. The Agency will
work with the RMS supplier to resolve data import problem.

4.11 Acceptance Certificate No
The ‘Acceptance Certificate’ is the formal notification of the Supplier that
the Agency accepts that the equipment is performing to specification.



The ‘Acceptance Certificate’ shall be issued within 24 hours <select appropriate
value> once the equipment has been successfully calibrated, validated and the
100 km field survey data collection trial in Clause 4.10 has been successfully
completed. The equipment warranty shall be effective starting from the date of the
issuance of the Acceptance Certificate.


World Bank Generic Data Collection Equipment Spec - 07 01 09 Road Data Collection Equipment Generic Specificationv1.1

World Bank Generic Data Collection Equipment Spec - 07 01 09 Road Data Collection Equipment Generic Specificationv1.1

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World Bank Generic Data Collection Equipment Spec - 07 01 09 Road Data Collection Equipment Generic Specificationv1.1