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TITLE:
by:
Maintenance of minor roads using the
Iengthman contractor system
T E Jones and R C Petts
Transport Research Laboratory
Crowthorne
Berkshire RG45 6AU
United Kingdom
PAl 256191
j
v JONES, T E and R C PETTS, 1991.
Maintenance of minor roads using the
Lengthman Contractor System. In:
Firthi Initerniational Conference on
Low Volume Roads, Raleigh, North
Carolina 19-23 May 1991. Tr-anspor-
tation Research Record 1291, Volume
1. Washington DC: Transportation Re-
search Board, National Research
Council, 4 1-52. MAINTENANCE OF MINOR ROADS USING
THE LENGTHMAN CONTRACTOR'SYSTEM
by
Dr T E Jones* and R C Petts**
"Transport and Road Research Laboratory, UK
**Intech Associates formerly of Howard Humphreys and Partners Ltd,
Consulting Engineers, UK
The work described in-this report forms part of the programme carried
out for the Overseas Development Administration, but any views
expressed are not necessarily those of the Administration.
Reproduced by permission of Her Britannic Majesty's Stationary Office FIFTH INTERNATIONAL CONFERENCE ON LOW VOLUME ROADS
PAPER: MAINTENANCE OF MINOR ROADS USING THE
LENGTHMAN CONTRACTOR SYSTEM
by
Dr T E JONES* and R C PETTS**
1 1ABSTRACT
This paper describes current development and research activities on the Minor Roads
Programme in Kenya.
The relatively rapid deterioration of unpaved roads compared to paved roads demands that
maintenance is programmed rather than responsive to changes in surface condition. Road
maintenance in developing countries is normally organised on a district or regional basis using
ministry teams or contractors. 'However, the use of lengthmen to undertake routine and
possibly recurrent maintenance activities may result in more rapid and cost effective
correction of deficiencies and an improved level of service in some circumstances.
The Minor Roads Programme is a labour-based improvement and maintenance programme
for low and medium trafficked roads in 28 districts of Kenya with a high agricultural
potential. The programme commenced in 1986 and is projected to improve 4500 km of roads
to gravel all-weather standard over a five year period and establish maintenance systems. The
programme will also maintain some 8000 km of roads constructed under the previous labour-
based Rural Access Roads Programme.
People living alongside the roads are utilised on a casual basis to carry out all improvements
and maintenance supported by simple agricultural equipment for certain operations,
particularly on the higher trafficked roads.
Routine maintenance on the roads is carried out using a Lengthman system. An ex-
construction worker is appointed to each section; typically 1.5 -2.0 km in length. He is
provided with the necessary handtools and is paid for working 3 days per week on the road.
This allows him time to continue to work on his land on other days.
The principal aim of the research reported in this paper was to establish productivity
standards for a range of routine and recurrent maintenance activities carried out by lengthmen
using mostly hand tools. The current research will evaluate the influence of geometry,
climate, traffic and materials on the amount of maintenance required and define optimum
lengths of road relative to labour inputs for these variables
*Head of Pavement Management Section, Overseas Unit, TRRL UK.
**Principal Engineer -Intech Associates, formerly Howard Humphreys and
Partners Ltd, Consulting Engineers, UK. Dr T E Jones and R C Petts1
SYNOPSIS
A network of more than 8000 km of Rural Access and Minor roads has been
constructed and maintained in Kenya using labour-based methods. Routine maintenance of
these roads is carried out using individua~lIengthmen contractors.
This Paper describes current research work designed to establish maintenance needs
and productivity standards. The results of the research will permit improved planning,
implementation and monitoring of labour-based road maintenance.
1. INTRODUCTION
The use of individual contractors or lengthmen to undertake routine maintenance over
specified lengths of road has been a recognised management technique for many years.
However, the effectiveness of the technique over a long period has seldom been monitored
in detail.
The Kenyan Rural Access Road Programme (RARP) was started in 1974. It's primary
objective was to construct farm-to-market access roads using a labour-based method in
districts with high agricultural potentiaL. By the end of 1986 approximately 8000 km of Rural
Access Roads had been completed in 26 districts and the majority of them gravelled and
maintained by individual lengthmen contractors.
Following the success of the RARP in constructing roads at low cost and with high
--- 7
1 Dr T E Jones and R C Petts 2
utilisation of local resources, the Government of Kenya decided to apply the same labour-
based methods to the improvement and maintenance of selected D and E roads, see Table 1,
which are categorised as Minor Roads(l). During the period 1986-1992 the Minor Roads
Programme (MRP) is projected to improve 4500 km of Minor Roads and to include them in
Kenya's overall maintenance strategy.
The research described in this Paper is concerned with the initial establishment of
maintenance productivity standards in the Minor Roads Programme and the determination of
the routine maintenance needs of Rural Access and Minor Roads.
For the Minor Roads Programme, routine maintenance is defined as all work required
within the road margin capable of being carried out by an individual lengthmen contractor.
Periodic maintenance of the roads includes regravelling and repairs to structures and this is
carried out by special units or contracting companies. Occasionally, urgent work is carried
out under various arrangements when the scope is beyond the capabilities of the lengthman
contractor.
2. DEVELOPMENT OF THE MAINTENANCE SYSTEM
Various methods were originally considered for the routine maintenance of Rural
Access Roads. For the chosen lengthman system an ex-construction worker was appointed
on a contract basis to each section of road, typically 1.5-2.0km in length. -He was provided
with hand tools and supervised once a month by an overseer to monitor the condition of the
road and to authorise payments for satisfactory work. The payment was based on the Dr T E Jones and R C Petts3
contractor carrying out 12 days of work per month on days of his choice. The contractor
could be replaced if he consistently performed badly.
The contractor lived adjacent to the road and would, therefore not re~quire government
accommodation or transport which consume considerable resources in a traditional equipment-
based maintenance system.
A. principal attraction of the system is the comparatively low level of e~quipment
required and consequently lessened support problems. This is coupled with a low foreign
exchange component which in 1981 was estimated to be only 10 per cent(l). This compares
with a typical foreign exchange component for equipment-based routine maintenance systems
of 50 per cent(2).
The lengthman system also creates productive paid employment in rural areas where
there are few opportunities for such work. The contractor is able to live at home with his
family and the part-time terms give him the opportunity to work on his own land as well.
Approximately 80 per cent of the direct costs of the system were estimated to be paid
directly to the contractors in 1982. The system also enables maintenance to be achieved
throughout the year on each section of road. The responsibility for the maintenance of each
road section lies completely with one person who requires minimal logistic support.
Unfortunately, the establishment of the maintenance system did not attract the same
amount of research and development effort as the construction aspects of the programme.
3 Dr T E Jones and R C Petts4
It was erroneously assumed that the local administration and people would bring pressure to
bear on the contractors to maintain the roads to a good standard. The contractor's
appreciation of the maintenance requirements was taken for granted. The need for training
and supervision was underestimated and mechanical problems associated with the supervision
vehicles had an adverse effect.
It is now realised that the development of effective maintenance systems requires as
much, if not more, effort than construction or road improvement systems. In recognition of
these problems a Study of Maintenance of Rural Access Roads was commissioned in early
1985(3). The report showed the lengthman system to be quite effective. However, it
indicated a significant potential for improvement and the need for better direction and control
of the contractors. Extensive discussion of the maintenance issues has enabled the principal
problems to be identified and appropriate strategies developed for tackling them.
In particular there was a need to more accurately determine the maintenance
requirements of Rural Access Roads and Minor Roads under various conditions of rainfall,
alignment, pavement/soil type and traffic. Rural Access Roads have a 4 m wide gravelled
running surface whereas the Minor Road standard is 5.4 metres. See Figs 1 and 2.
Methods of determining required maintenance resources and their deployment,
direction and control needed to be developed. Arrangements for
dealing with urgent works such as washouts and culvert breakages should be. formalised. The
methods of identifying spot regravelling and full regravelling required to be developed and
the various options for carrying out this work eg by animal-drawn haulage and casual labour
4 Dr T E Jones and R C Petts5
or small scale contractors, needed to be investigated. There was an urgent requirement to
ease the supervision burden of the maintenance overseers because of the minimal time that
they could allocate to each contractor and the mechanical problems that will always exist to
a degree, even with the low equipment component of the system. The scope for the use of
headmen, responsible for a small number of contractors, needed to be developed as well as
the methods of training, directing and monitoring them. On the technical side there was the
problem of maintaining a satisfactory longitudinal profile especially for the wider, more
heavily, trafficked Minor Roads. There was also the question of safety for lengthmen working
on the carriageway of the more heavily trafficked roads (> 50 Vehicles per day).
Consideration had to be given to the use of simple tractor-drawn mechanical graders or drags
for maintaining the running surface in these circumstances; with pothole patching support and
all off-carriageway work by the lengthmen.
The lengthman concept has been adopted for the maintenance of Rural Access and
Minor Roads under the new programme. However a number of major improvements to the
system have been initiated or planned. Studies of particular maintenance aspects are being
carried out as part of this process.
1
5 Dr T E Jones and R C Petts6
The main areas of improvement to the maintenance system are as follows:
1. The setting of fair contract lengths for the lengthmen including-objective consideration
of the factors influencing the amount of maintenance required.
2. The supervision of lengthmen activities and concentration on one routine maintenance
activity at a time.
3. Arranging for the lengthfnen to work progressively from one end of a section to the
other on a specified activity, easing supervision and control.
4. The establishment of realistic task rates for routine maintenance activities.
5. The setting of priorities for routine maintenance activities according to season.
6. The establishment of reference stations on each lengthman's section for control and
reporting purposes.
7.. The introduction-of-both-wor-king and non-working-headmen-in appropriate situations
to control work between Overseer's visits.
8. The introduction of control aids for headmen.
9. The introduction of an objective assessment of routine maintenance performance
6 Dr T.E Jones and R C Petts7
incorporated in an annual inspection system. This system will also allow periodic
maintenance work to be identified and monitored.
10. A training programme including formal and on-the-job training, and demonstration
sites in each district.
11. Allocation of the highest priority to the provision, servicing and repair of routine
maintenance overseer's motorcycles.
Items 1 and 4 are the subject of the current study described in this Paper. Other
initiatives are being taken to bring about the other improvements.
Phase I of the study has already established routine maintenance productivity standards
(task rates).
Phase II of the study will monitor the maintenance requirements of Rural Access
Roads and Minor Roads under the range of principal influential factors experienced; namely
rainfall, gradient, traffic and surface characteristics. Figure 3 depicts the flow diagram for
the study. Whilst Fig 4 details the proposed district'structure for the established maintenance
organisation.
7 Dr T E Jones and R C Petts8
3. PHASE I: ESTABLISHMENT OF MAINTENANCE
PRODUCTIVITY STANDARDS
3.1 Objective
Phase I of the study concentrated on the following objective:
Establish productivity standards for a range of routine maintenance activities utilising
hand tools.
The following activities in Table 2 were identified as the principal routine maintenance
operations for Rural Access and Minor roads for which productivity levels were established
in the study. Some of the operations are illustrated in Plates 1 to 8.
3.2 Methodology
Phase I of the study was conducted in Kisii and South Nyanza districts between October 1988
and March 1989, a period which conveniently overlapped wet and dry seasons in both
districts.
Kisii is a high rainfall district with generally cohesive 'red coffee' soils at approximately
1800m elevation and has an annual rainfall of between 1500 and 2000 mm. South Nyanza
is a drier district with predominantly sandy and 'black cotton' soils at approximately 1 lO0m
elevation; annual rainfall there being between 1000 and 1500 mm. Programme districts are
8 Dr T E Jones and R C Petts9
illustrated in Fig 5.
The two districts are considered to be typical of many MRP districts, so that the productivity
data derived may be applicable across the programme.
Three overseers were seconded to the study team each supervising up to 14 maintenance
contractors with the assistance of 2 'non-working' headmen. This contrasts to the supervision
ratio planned for the MRP which would typically be one overseer to 8 headmen to 80
lengthmen. In some areas 'wor'king headmen ' have their own maintenance section as well
as supervision responsibilities over other lengthmen.
The contractors were generally working on their own separate sections prior to the study.
However, during the study they were brought together in small groups of seven under each
non-working headman for ease of supervision. Prior to the commencement of data collection
the contractors and headmen were given approximately 2 weeks of training by the overseers.
The lengthmen were given individual daily tasks on various maintenance activities along a
short section of road. Tasks were set daily by the overseers and monitored throughout the
day by both the overseers- and-headmen: --The starting and 'flnishing times were carefully
recorded for each task.
During the study the contractors were retained for approximately 7 hours..if tasks were not
completed. However they were released earlier, normally after 5 hours, if they finished their
work satisfactorily. Individuals were rotated between activities on successive days.
1
9 Dr T E Jones and R C Petts 1
Various levels of difficulty were defined for each maintenance activity and some of the
activities had to be broken into two component operations for ease of control or measurement.
Forms were developed to record the relevant technical and personnel data for each day's task.
This included name, sex and age of individuals. Reports were thoroughly checked before
entering on the microcomputer database, using dBase 1II Plus software.
Productivities were calculated in terms of quantity of work completed per hour. These values
were then adjusted to represent the quantity of work that could be expected for a standard 5
hour closely supervised workday. This was adopted as the basis for development of daily
productivity standards. In the normal situation the lengthman is subjected to a lower level
of supervision. He/she is nominally paid for 8 hours of work and the 5 hour supervised
standard was considered to be an appropriate target for the MRP.
From the data gathered, comparisons were made between performance related to age groups,
sex and districts, and whether the set tasks were successfully completed or not.
3.3 Phase I Study Results
A total of 1960 task-days of data was collected. Of the eleven originally planned activities
*(see Table 2) five were sub divided into two operations; in effect making [6 activities to be
monitored, see Table 3. For each activity up to 4 degrees of difficulty were defined and
observations made based on these divisions. As many as 47 observations were made on an
10 Dr T E Jones and R C Petts 1
individual activity (Activity R3). Records were unobtainable for only one combination of
activity-difficulty. For only 4 activity-difficulty combinations were 5 or less observations
made. The lack of data on these combinations reflects their low occurrence in general
RAR/MR maintenance operations.
The observations were taken on seven road sirtes two of which were constructed to Minor
Road cross section standards. From the observations taken it was not possible to detect a
difference in productivity between Rural Access Roads and Minor Roads.
Little difference was observed in productivities between age groups, districts or sexes. The
mnost significant observation was that contractors who completed their tasks, and thus left
work early, worked significantly harder (by up to 30%) than those who failed to do so. This
trend shows up fairly consistently throughout the results and is (i) an indication of the quality
of the data gathered and (ii) a strong argument for establishing a task based system with fair
and achievable targets.
The standard deviation for each data set was calculated and used to define the representative
range of productivity for the task around the mean of the observations. These ranges were
then used for the final comparisons and are shown in Table 4 (Kisii District) and Table 5
(South Nyanza District).
The productivity results shown in these tables can be used as standards for the MRP.
However it should be appreciated that these results were obtained under most favourable
supervision conditions with trained lengthmen and motivated overseers. They should be
11 Dr T E lones and R C Petts 1
treated as reference points to strive for by MRP personnel.
4. PHASE IIL THE IDENTIFICATION OF ROUTINE MAINTENANCE
REQUIREMENTS
4.1. Objectives
The Principal objectives of Phase II of the study are:-
a) To determine the influence of geometry, climate, traffic and pavement materials on
the amount of routine maintenance required expressed in terms of the 16 standard
activities.
b) To determine optimum maintainable lengths of road relative to labour inputs under
various soil, topographic, climatic and, traffic conditions.
4.2 Methodology
In order to achieve these objectives. detailed observations -will--be taken over a period of 12
months on existing sections of Rural Access and Minor Roads which are already under
routine maintenance.
4.3 Selection of Road Sections and Preparation Work
12 Dr T E Jones and R C Petts 13
The Kenyan Rural Access and Minor Roads have been constructed over a wide range of
climates, vertical gradients, soil types and traffic levels. Traffic currently using these roads
varies from less than 10 to over 100 vehicles per day. Selection will be made of suitable
sections of existing roads encompassing as many of these variables as possible.
The most important variables considered to affect the performance of the roads are classified
as follows:-
(1) Traffic <20, 20-50, and >50 vpd
(2) Annual Rainfall <500mm, 500-150Omm, > 1500mm
(3) Vertical Gradients < 4%, 4-8 %, >8 %
(4) Surface Materials: Gravelled and ungravelled.
In addition, the following parameters will also be recorded at the beginning and end of the
study:-
(a) width of carriageway
(b) average crossfall
(c) length of section maintained
(d) frequency of supervision
(e) thickness of gravel
As a `control" some sections will be selected on which no maintenance (other than emergency
repairs) will be carried out during the study. Dr T E Jones and R C Petts 1
Minor Roads Programme (MRP) personnel will be responsible for the initial identification
of roads suitable for inclusion in the study. A total of about 50 sections of roads will be
required to cover all the principal variables (however some sections may be on the same
road). Each section will be of a length maintainable by one individual contractor ie 1-2kmi
approximately.
The study roads will mainly be concentrated in 3 areas, Na~kurti/Naivasha, South Nyanza and
Kisii, to cover a wider range of variables, some road sections may be located outside these
areas.
Each road will be inspected by a supervising engineer to confirm its suitability and to carry
out a detailed condition survey. This will include identifying maintenance defects and
preparing a schedule of repairs.
The supervising engineer will also be responsible for the final demarcation of the road
sections to be included in the study, and will also ensure that each road section is clearly
marked with a signboard indicating the section reference number. This initial survey will
record the relevant details of soil/gravel type, mean gradient, gravel thickness, road width,
etc for each contractor's section.
MRP personnel will be responsible for carrying out the repairs to bring the road to an
*acceptable and maintainable standard within a reasonable period of time.to suit the study
programme. A check inspection on completion of the repair works will be carried out by the
supervising engineer.
14 Dr T E Jones and R C Petts 1
Prior to the commencement of the study and at the end of the study manual traffic counts will
be taken over 7 consecutive days and 2 nights on each road and thereafter on 1 day per
month.
Rainfall gauges will be established in the Vicinity of each road to monitor daily rainfall and
surface roughness measurement will be carried out on each road section using the MRP
vehicle mounted bump integrator on a monthly basis.
4.4 Study data collection
The study will be carried out over a period of 12 consecutive months on each road section
with an additional 1 month's trial data collection at the commencement of the study.
Every month an MRP inspector, under the direction of the supervising engineer, will visit
each road and record and assess the previous month's work. He will also survey the road
and locate, quantify and record all defects or outstanding maintenance requirements. He will
inform the overseer supervising the road of the maintenance programme for the following
month based on the productivity norms established by the MRP under `Maintenance Study
II Phase I Productiv ity Standards` which was completed in. early 1989(4).
Each month the schedule for each contractor will show:-
(a) Maintenance work achieved
(b) Outstanding work required
---- 7
15. Dr T E Jones and R C Petts 16
If the maintenance contractor is falling behind with the work then he will be given additional
time to ensure that the road condition is satisfactorily maintained (provided the delays are not
due to inefficiency on the part of the contractor). In certain cases additional personnel may
be temporarily employed to help catch up on any backlog of work.
All survey data including the regular monitoring of rainfall, roughness and traffic will be
input to a micro-computer data base and analysed to establish relationships between the extent
of each maintenance operation required and the monitored characteristics of the road section.
5. PROJECT OUTPUT
The two phases of the study should enable the labour based maintenance of Rural
Access and Minor Roads to be significantly improved.
The research in Phases I and II will result in:
1. A rational basis for implementing routine maintenance using the 'length man' principle
over the range of site conditions experienced in Kenya.
2. Identification of any shortcomings in the lengthman system.
3. The provision of data to prepare realistic estimates of resources and costs for routine
maintenance. Dr T E Jones and R C Petts 1
4. More realistic productivity standards for use in the TRRL, guide to maintenance
management for District Engineers(5).
These results will permit more effective planning, execution and monitoring of gravel roads
maintenance particularly where lengthmen contractors are used.
6. OTHER INITIATIVES
In addition to the Phase I and Phase 11 studies described in this paper the Ministry of
Public Works has taken a number of other initiatives to improve the lengthman maintenance
system.
The improvements identified and described in Section 2 have been adopted as policy for the
MR.P. Pending the results of the two study phases, including finalisation of productivity
standards and maintenance needs, other improvements will be introduced, through a planned
programme of training, and demonstration sites.
In recent TRRI, studies, research on unpaved roads has often concentrated on comparisons
between motorised graders and tractor drawn graders(6).
The maintenance project in Kenya has afforded the opportunity of evaluating maintenance
strategies incorporating a 'mix' of towed graders and contract lengthmen... The intention is
to investigate a mix of low cost equipment and labour based maintenance during Phase HI of
the project. This strategy will be used only on the higher trafficked roads (> 50 vpd) of the
17 Dr TE Jones and R CPetts 18
Minor Roads Programme. It is intended that the towed grader will only lightly grade the
running surface, with pothole patching and all side drainage and off-carriageway work being
carried out by the lengthmen.
The results from this additional research will provide new and valuable information on the
most appropriate maintenance strategies utilising low cast techniques for gravel roads in
developing countries.
7. RECOMMENDATIONS FROM THE PHASE I INVESTIGATION
The results of Phase I of the study are summarised in Tables 4 and 5. For the
guidelines to be applicable in each district of Kenya some allowance, based on previous
experience, will be required to adjust the separate task rates for the particular workforce
involved.
The subdivision of five of the maintenance activities permits better control and measurement
of these tasks and has been recommended for incorporation into the present reporting system.
The guidelines themselves have been established under virtually ideal.supervisory conditions
with a well trained workforce under the control of motivated overseers. As such, the
guidelines represent the best overall productivities that can be expected under conditions in
Kisii and South Nyanza districts. They should be treated as realistic targets which can be
strived for as the management of routine maintenance is improved. More importantly
perhaps, the guidelines provide a reference against which the performance of contractors can Dr T E Jones and R C Petts 19
be assessed.
The maintenance activities are not directly comparable to those of construction and
improvement work. A number of activities are of a similar nature although there are
differences in scale of work and method of -working and measurement. Where a broad
comparison is possible the productivities achieved for maintenance activities are somewhat
below the RARP/MRP construction productivity standards. This reflects the generally
smaller scale and dispersed nature of the maintenance work.
At the commencement of Phase 1 it was found that many contractors and headmen did not
fully appreciate what the various maintenance tasks were, how they should be carried out and
controlled, and the methods to be used for measuring them. There was an obvious need for
training particularly since, if the task system is to work effectively, the headmen must take
on a much stricter supervisory function than they have in the past. Besides their direct
supervisory function, headmen must also become fully conversant with the methods for
measuring each activity so that they can assist the overseers in their overall management role.
It will be important to introduce the experience gained from Phase I, and in due course Phase
II into the training and maintenance operations of the 'MRP.
The lengthmen, headmen and overseers should have a clear understanding of the reasons for
and methods of desilting. It is just as important that they appreciate when it is not required
due to established vegetation and good drainage conditions. Dr T E Jones and R C Petts 20
Recommendations include updating of the planning and reporting system and introduction of
the new productivity standards.
Training material, manuals and courses will also be necessary.
ACKNOWLEDGEMENTS
The Authors wish to acknowledge the support given to the research project by Eng
S Otonglo (Chief Engineer Roads) and the staff of the Ministry of Public Works especially
that of Eng B Ariga (Minor Roads Programme Co-ordinator). Also the Swiss Development
Corporation who funded Phases I and II of the Project.
The contribution of the British Transport and Road Research Laboratory forms part
of the research programme of the Overseas Unit (Unit Head: J S Yerrell) and is published
by permission of the Director, Transport and Road Research Laboratory.
Graham Williams was the Project Engineer for the Phase I field work.
REFERENCES
1 . Petts, R C, "Maintenance of Rural Access Roads and the Scope of the Extension of
Labour Based Methods into the Routine Maintenance of Classified Roads in Kenya".
ILO and Ministry of Transport and Communications (1982). Dr TEJo nes and R CPetts 21
2. Howard Humphreys and Partners, `Maintenance Study" Main Report Vol 1, United
Republic of Tanzania, Ministr~y of Communications and Works (1984).
3. Ove Amup and Partners for ILO, "Kenya Rural Road Maintenance Study" -Draft
Final Report (1986).
4. Howard Humphreys and Partners, Routine Maintenance Study II Phase I, Productivity
Standards, Final Report, for Ministry of Public Works, Kenya and Swiss
Development Cooperation'(1989).
5. TRR.L Overseas Unit, Maintenance Management for District Engineers. Overseas
Road Note 1. Transport and Road Research Laboratory, Crowthome Berks (1987)
Second Edition.
6. Jones, T E and Robinson R -'A Study of the Cost Effectiveness of Grading Unpaved
Roads in Developing Countries`. Department of Transport, TRR.L Research Report
91. Crowthome, Berks (1986). LIST OF TABLES
TABLE 1 Kenya Road Network Under the Responsibility of the Ministry of
Public Works: (kmn)
TABLE 2 Maintenance Activity
TABLE 3 Revised Activity Schedule
TABLE 4 Productivity Ranges for Routine Maintenance Wet Highland Areas
(KISI1 District)
TABLE S Productivity Ranges for Routine Maintenance Dry Lowland Areas
(S Nyanza District) Table 1.
NOTE (1) :
(2)
Kenya Road Network Under the Responsibility of the
Ministry of Public Works: (Kmn)
Network at September 1990.
Network at June 1990.
CATEGORY BITUMEN EARTH/GRAVEL TOTAL
A. INTERNATIONAL TRUNK ROADS (1) 2,08-971 3,579
B. NATIONAL TRUNK ROADS (1) 1,308 1,443 2,751
C. PRIMARY ROADS (1) 2,293 5,476 7,769
D. SECONDARY ROADS (1) 1,041 10,074 11,115
E. MINOR ROADS (1) 512 25,754 26,266
SPECIAL PURPOSE ROADS (1) 166 2,931 3,097
RURAL ACCESS ROADS (2) 15 7,962 7,977
TOTAL 7,943 54,611 62554
1 Dr T E Jones and R C Petts
Table 2. Maintenance Activity
Activity Code Description
Rl Inspection and remove. obstructions
R2 Clean culverts and inlets/outlets
R3 Repair culvert headwalls
R4 Clean mitre drains
R5 Clean side drains
R6 Repair scour checks and side drain erosion
R7 Repair erosion on shoulders
R8 Fill potholes in carriageway
R9 Grub edge and reshape carriageway
R10 Cut grass in the side drains
R11 Clear bush Dr T E Jones and R C Petts
Table 3. Revised activity schedule
Activity
Code
R1
R2A
R2B
R3
R4
R5
R6A
R6B
R7A
R7B
.R8A
R8B
R9A
R9B
R1O
R11
Maintained Activity
Inspection and Removal of Obstructions
Clean Cuiverts and Inlets
Clean Culvert Outfalis
Repair Culvert Headwails
Clean Mitre Drains
Clean Side Drains
Repair Scour Checks
Repair Side Drain Erosion
Repair Shoulder Erosion
Grass Planting
Fill-Potholes in Carriageway
Fill Ruts in Carriageway
Grub Edge of Carriageway
Reshape Carriageway
Grass Cutting
Bush Clearing Rl :Inspection1 .5 lus/day Table 4. PRODUCTIVITY RANGES FOR ROUTINE MAINTEN.e4.:CE- WET HIGHLAND AREA (KIS1I DISTRICT)
TASK DIFFICULTY ACTVITY UNIT i2 '3 4 NOTES
R2A Clean Culvert* AS 2 5 I-I' 1 1½-t,3 1 Difficulty -Ski: depth in culvert.
Inlet shov.n Culvert /day Days/Culvert Days/Culvert Das/ulvc: .Up to 1/4 2.1/' :o '- 3.i to 3/4 4. Over 3/L
R25 Clean Culvert =n/day . 45-60 30-45 15-30 Difficulty -Silt depth Outfalls.I_______I______j 1. Up to 10c=. 2. 10 to 20cm 3. Over 20cm
1R3 Repair Culvert :1o/ 5410 3-5 11 Difficulty -Type of repair Seadwalls day I. M1inor repairs 2. major repairs
jR4. Clean Mtitre m/day . 50 -6 5 35-50 2 5- 35 Difficulty -Silt dep:h DrainsI 1. Up to 10em 2. 1.0 to 15c., 3. Over 15cm
R5 Clean Side 0/a 575 35-552-5 Difficulty -S~ilt dep:h Drains . .UP to 10cm 2. 1C to 15cm 3. Over 15cm
IRSA Repair Scour No/ 3-8 5-9 Difficulty -Type of scour check Checks day I .Wood 2. Stone
?z.6a Repair Side m/day 90-1110 70-90 50-70 Difficulty -Depth of erision Drain Erosion - 1. Up to 15c= 2. 15 to 30c= 3. Over 30cm
'R7A Repair Shoulder m/day 85-i10 60-8 I 06 ifcly-Dpth of erosion Eros ion 1 .Up -to 10cmi 2. 10 to 15cz 3. Over 15cm
G7 Cass ?laitrig en.I~ 90-110 70-90 60-710 Difc~y- at-gudth 1. Up to O.5m 2. 0.5 co 1.Om 3. Over 1.Om
RSA Illl Potholes ~ rs 23-30 16-23 1.1-16 7-Il Difficulty -Hauling distance in Carriageway /day 1 - - .N:o Hau! 2. Up to lO0m 3. 1O0n to 200m
____________________ _______________________ I 4. Over 200m
:Rss Fill. Ruts in m /day 60-80 40-60 30 -La 10-20 Difficulty -Hauling distance Carriageway f .No haul 2. Up to lO0m 3. 100 to 200o j4.Over 20
R9A Cru Edge of m r/day I 230,300 160-230 100-160I Difficulty -'Jid-h of grubbing
Carr__ _ _ __ _ _ I_ _ __ _I__ _ _ __ _ _ g_ _ __ _ _ ._ _ __ _ _ __ _ _ __ _ .UP t 0.5w 2. 0.5 to 1.0m 3. Over 1.0w
R93.: Reshape [ /day 55-80 40-55 Difficulty -Type of reshaping
Carriageway ~~~~~~~~~~~~~~~~1. Light (Up to 75n,) 2. Heavy (Over 75mm)
RiO. Light mn/day 4.00-450 220-300 150-220 Difficulty -Vidth of grass cutting .Grass __ _ _ _ _ _ _ _ _ _ _ I_ _ _ _ _ _ _ _ _ _ _ _ _ _I_ _ _ _ _ _ _ _ _ _ _ _ _ .Up to 1.0. 2. 1.0 to 2C0m 3. Oyer 2.Om .Catting -'- Dense n/day 275-350 200-275 150-200
~Rl Light 0/day 400-450 220-300 150-220 Difficulty -Uid-h of bush 8buzh __ _ _ _ _ _ _ _ _ _ _ I_ _ _ _ _ _ _ __ _ _ _ _ _I_ _ _ _ _ _ __ _ _ _ _ -1. Up co l.in 2. 1.0 to 2 COm 3. Over 2.0m
Dense m/day 250-300 200-250 150-200
All tasks except reshap;.ng are measured along one side of the road only. RI : Inspecrion1.5 kms/day Table 5. PRODUCTIVITY RANGES FOR ROUTINE MAINTENA.NCE DRY LOVIJLAND AREAS (S NYAN4ZA DISTRICT)
TAK DIFFICULTY 1ACTIVITY UNIT 12TA '3NOTES
;R2A Clean Culvrt- A 25 -i l'-33- Difficulty -Silt depth in culvert,. In ict cho.-n Culverts/dayl Dy/u~r Days/Culver c Days/Culvert ! . tp o if., 2.1/4 to ', 3.1t to 3/4 4. Over 3/4: Tas'ks for 600 dla culverts uith 7 rir.~s
R23 Clean Culvert ./day 45.60 - Di'ru15y30 SIlt depth 3 vr2c
!R3 Repair Culvert No/ I 5-10 3-5 Difficulty -Type of repair M~eadualls da y j- 1. minor repairs 2. Major repairs
R4 Clean Mitre rn/day ~~~~50-65 35-50255 Difficulty -Silt depth
* rains 1 .UD to 10cm 2. 10 to 15cm 3. Over 15cm
:R5 Clean Side =/day soft 45-60 soft 35-45 soft 25-35 Difficulcy -Silt depth * Drains hard 25-35 hard 20-25 hard 20-25 1. Ulp to 10c. 2. 10 to 15cm 3. Over 15cm
RS epair Scour No/ 3-8 5 -9 Difficult). --type of scour check * Checks day I I Wood 2.Stone
~R6B Repair Side c/day 75-100 4.0-75 20-40 ifcl -Depth of erosion Drain Erosion Ii. Un ro 15c= 2. 15 to 30cm 3. Over 30cm
P.7A Repair Shoulder 0/day 85-110 60-85 40-60 Diffic.l:y -Depth of erosion s-rosio n 1 .Up to tOco~ 2. 1.0 to 1.5cm 3. Over 15cm
7.78 Crass Planting n/day 90-110 70-6097 Diffziculty -?lanc ing vidrh
___________________ _______ ____________ t-60-70 .U~p to 0 5. 2. 0.5 to I. m 3. Over I.0n
:R8A Fill Potholes w.brvs 20-3D 14-20 10-14 7-10 iDiffi;cult: -. Hauling distance in Carriageuay /day l's E Maul Up to lO0m 3. lO11n to 2100i 4. Over 20Cm
:RBB Fill Ruts in 0/day 40-60 20-40 10-20 5-10 Difficul:) -Hauling distance Carriagevay I. No haul 2. Up to lO0m 3. 100 to 200m 4. Over 200.
,R9A Grub Edge of m/day 150-220 80-150 50-60 Difficult)' -Uidth of grubbing Carriageway j .Up .to O.5m 2. 0.5 to 1.Om 3. Over I.0m
1R9S.: Reshape m/day 5 5- 80 4-0-55 1Dfiut Type of reshaping Carriagew.ay I. Light '(Up to 75en) 2. Heavy (Over 75-s)
RIO Light 0/day 2 7 5- 350 200 -2 75 150-200 Difficulty -Wisdth of grass cutting Crass____________ _J 1. UP to 1.00 2. 1.0 to 2.Om 3. Over 2.On
Cutting Dense 0/day 275-350 200-275 150-200
7.11 Light m/day 4.00-450 220-300 150-220 Difficulty -Uidth of bush 3ush __ _ _ _ _ _ _ j__ _ _ __ _ _ _ _ _ 1. Up to I.0m 2. 1.0 to 2DOm 3. Over 2.Orn
Cutting Dense m/day 250-300 200-250 150-2001
*All tasks except reshaping are measured along one side of the road only.
------- LIST OF FIGURES
Rural access road.' Standard cross section
Minor road. Standard cross section
Flow diagram of the research programme
Proposed MRIRA programme district maintenance unit
Kenya minor roads programme. Programme districts
FIGURE 1
FIGURE 2
FIGURE 3
FIGURE 4
FIGURE 5 DR T E JONES and R C PETTS
14 ~~~~~~~~~~7.3010
1.40 4.50 I- . 1.40 0
5-10% 5 -1 0%
-. 0.10 Compacted.
iGravel
j~~401 0.25 4.00.25 1.00 040 K2i 1.00 Li ,0 im0----
TI I I
Fig.1 Rural access road. Standard cross section
All dimensions in metres
0.50 0.60 1.20 5.40
2.7 0 2.70
0.12 Compacted 5-10%.---------- __ _ __ _ __ _
Fig.2 Minor road. Standard cross section
Notes: Camber profile depends on whether constructed from arisings of one ditch or two. Other sections apply for Black Cotton soil. severe terrain or embankment situations
PA 1838.1 .2
ill
omi-C,
illw
1.20 0.60
0.35
t
1 1
4 DR T E JONES and R C PETTS
INITIAL SELECTION OF SITES
FOR PRODUCTIVITY MONITORING
& MAINTENANCE MONITORING
SELECT & TRAIN SUPERVISORY
MAISNTNNCEL ACNTIVITY
& CLNGTHRNCNACTORS
SUTRVIEY SELEUCTEDIT
ROADL S SECTIONOFSIE
P HA SE 1
P HA SE 2
k
BRING ROAD SECTIONS UP
TO BASELINE CONDITION
MONTHLY SITE VISITS TO
MONITOR PERFORMANCE
MONITOR ROUGHNESS,
RAINFALL & TRAFFIC
7~~ ANALYSE.DATA
Fig 3. Flow diagram of the research programme
1 CC CC U) wuz W~C~~L
>: C W Cd) 0 a: W Uri) fZ W Lu < z Wo~ L
L cc rr...a..O )u< (D D W U) C.
z
a0 ~