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RHD Operational Procedure Zonal Operation Wing
 
Zonal Operations
 
OP/ZF/2.3 - Routine and Periodic Maintenance Works
 
Purpose and Scope :

This procedure describes Routine and Periodic Maintenance works for Roads under RHD. Both Routine and Periodic Maintenance works are done for keeping the RHD Roads smooth, safe and cost effective for Road users. These operations are of utmost importance for RHD to provide a trouble free and safe Road Network to the public. Maintenance of Roads helps keeping the vehicle operating cost lower, reduces accident, helps achieve a satisfactory level of rate of return.
 
Definitions :

HDM-4

HDM-4 is computer software for Highway Development and Maintenance Management System. It is a decision making tool for checking the Engineering and Economic viability of the investments in road projects. The World Bank has developed it for global use.

HDM-4 is the new windows version after HDM-III with incorporation of many new features so that it can be used in any locality of the world with any environmental and engineering situation.

Bangladesh has been using HDM software since long. The Roads & Highways Department (RHD) is the main user of this software.

For the maintenance of the road, the user might have various maintenance strategies. HDM can calculate the economic indicators like NPV, IRR etc. for every option of the maintenance strategies for the projected analysis period. The most beneficial maintenance option will be one that gives the maximum economic return.

HDM -4 is used for running programme analysis. It is the analysis for doing the yearly maintenance programme or for the multi-year rolling programme. The programme analysis tool has been incorporated in HDM-4 for easy analysis of the whole road network for identifying the candidate road sections for the maintenance for a particular budget period. For the constraint budget, the economic criterion for selecting the candidate road is the maximisation of NPV/cost.

RHD has prepared the yearly maintenance programme for the financial year 2000-2001 by doing this programme analysis for the bituminous roads of the whole road network.

By doing the programme analysis one can get the following:

Identify the candidate road sections for maintenance;

Determine the alternative improvements,

Optimisation of the programme in case of budget constraints,

Obtain the optimised list of projects for the budget period.
 
Responsibility :

CE-RHD - receives budget grant from MOF through MOC under Revenue head and allocates the fund for Routine and Periodic Maintenance works against assessment made through Road condition survey, Bridge condition survey, Roughness survey, Traffic survey and HDM4.

ACE-Field Zone - approves Annual programme for maintenance works for his zone according to budget grant Under Revenue head.

SE-Field Circle - ensures that Routine and Maintenance works are done under his circle according to approved programme, budget grant and quality control requirements.

EE-Field Division - is responsible to execute Routine and Periodic maintenance works through his SDEs, AEs, W/As and contractors according to approved programme, budget grant and Quality Control requirements.

SDEs-Field Sub-Divisions - supervise the execution of maintenance works according to the programme, budget grant and Quality Control requirements.
 
Method :

Preventive Road/Bridge Maintenance Works of RHD are usually classified as either Routine or Periodic. Routine maintenance consists of minor works that must be carried out at frequent intervals, usually several times a year. These operations are typically small scale or simple but widely dispersed and require semi-skilled or un-skilled manpower. Periodic maintenance consists of works of comparative larger volume that must be carried out every few years. These are normally large scale and require specialised equipment and skilled resources. These operations are costly and require specific identification and planning. The Routine and Periodic Maintenance works carried out by RHD are as follows:

1. Routine Maintenance Works
The Routine Maintenance Works to be carried out by RHD during a year are determined on the basis of annual Road condition survey, Bridge condition survey, Roughness survey, Traffic survey and analysis using HDM4. The works are then included in the annual programme against budget allocations under Revenue head approved by ACE of zone. The works may be carried out directly by engaging departmental labours or through contract. These works consist of a) Maintenance of Roadside areas; b) Maintenance of road surface; c) Maintenance of drainage, d) Maintenance of bridges and e) Maintenance of traffic control devices. These operations of Routine Maintenance are detailed below:

a) Routine Maintenance of Roadside areas
Roadside areas include the shoulders, side slopes, beams, borrow pits and all surface areas within the Right-of-way except the carriageway.
Routine maintenance of Road side areas include:
Removal of obstruction from shoulders e.g. rocks, trees/branches, soil heaps, wind blown sand, abandoned vehicles/debris,
Reshaping, regarding and compacting shoulder surface to the correct level including adding some material if necessary.
Vegetation controlling on the shoulder by removing grass, weeds, bushes.
Vegetation controlling in slope by cutting overgrown grass, bush clearing and tree trimming.
Preventing surface water erosion or repairing of slopes by providing
1. reducing slope angle;
2. clearing slip material;
3. surcharging the slope or toe;
4. gabion
5. cribwork,
6. masonry retaining wall or
7. concrete retaining wall

b) Routine maintenance of Road surface
Ideally, there would be no requirement for surface repairs to be included under the routine maintenance category. However, this is rarely the case. Consequently, for Bangladesh, the following are considered to be the limits for road surface maintenance works:
i) For bitumen-surfaced Roads
Pot hole repairs - Maximum 150 potholes of size 30mm x 30mm x 10mm in any one kilometre
Edge repairs - Maximum 100 metres in any kilometre
Crack sealing - Maximum 150 m2 in any one kilometre
ii) For Herring Bone Brick Roads
patching - Maximum 100 m2 in any one kilometre
iii) For Earth Roads
Manual Reshaping 2 times per year
Routine maintenance of road surface includes:
Preventing bleeding of bituminous road surface by sanding. It involves scattering heated (as heated for seal coat) coarse sand up to 5 mm over the bleeding surface and then spreading the sand evenly by a broom.
Repairing cracks by local sealing. First of all, the area should be swept clean and the surface should be dry. The affected area of surfacing to be covered is marked by chalk. Binder is then distributed over the surface by a spray lance or a watering can at the rate of 1.5 kg/m2 for bitumen emulsion and 1kg/m2 for cut back bitumen. The area sprayed by the binder is then covered with coarse sand upto 5mm (when dealing with cracks) or chippings of 6-10 mm size (for local surfacing repairs & to be compacted with small rollers).
Repairing closely spaced cracks by sealing cracks with bituminous slurry. To accomplish this task, the area to be repaired is outlined with chalk. Slurry is produced by mixing bitumen emulsion with coarse sand, up to 5mm, in the proportion of sand 20 litres and emulsion 6 litres. The whole marked out area is then covered with the slurry; spread out by a squeeze, in a thin layer, approximately 5 mm thick. The slurry must be allowed to dry before allowing traffic over the area.
Repairing isolated cracks by filling them with hot cut back bitumen. The surface is swept clean. Hot cut back bitumen is then sprayed by a spray lance or watering can on the surface following the line of the crack. The width of binder spread should be kept as small as possible. Then, coarse sand is scattered over the strip of the binder by a shovel.
Repairing subsidence of surface and surface irregularities due to shoving by filling with hot bituminous mix.
The surface of the depressions is swept clean and it should be dry. The area is outlined with chalk. High spots in the depressed area are removed with a pickaxe. Edges of the area are trimmed to lower them to ensure a flush edge on completion of the filling work. Hot cut back bitumen is applied as tack coat on the surface with a spray lance or watering can at a rate of 0.5 kg/m2. The depressed area is then filled with hot bituminous mix using a rake and leaving an excess thickness of about one third of the depth of the depression to allow for compaction. The bituminous mix thus laid is compacted thoroughly using a small vibrating roller or a three drum steel roller until finished level is 3 mm proud of the surrounding surface. The surface is then sealed by a seal coat to prevent penetration of water.
Repairing local loss of aggregate in the surface by surfacing patching. This is one of the most common treatments on RHD roads.
The area is to be swept clean and the surface must be dry. Surfacing to be repaired is outlined by chalk.
The surface is cut back so the edge is deep enough to receive materials and to allow a level edge on completion.
The area to be repaired is sealed with cold emulsion or hot cut back bitumen and a tack coat is provided at 1.5kg/m2 for bitumen emulsion or 1kg/m2 for cut back bitumen. Then, apply chippings (such as 6-10 mm size) to ensure a complete coverage. Thereafter, the chippings should be lightly rolled using a roller.
Alternatively, hot cut back bitumen is applied to the area of repair with a spray lance or watering can at a rate of 0.5kg/m2 to form a tack coat. Then, fine premixed bituminous material (made from material up to 5 mm size) is spread over the area evenly and compacted to the level of the surrounding surface, using a roller, vibrating plate or rammer.
Repairing area cracking, ruts and depressions, edge subsidence, edge surface failure, potholes, shoving or any other repair deeper than 1 cm by Base Patching.
The area is marked out with chalk.
All material from within the marked out area of the road surface is removed. The depth of the hole is increased until firm, dry material is found out and then the walls of the hole are trimmed so that they are vertical. If water or excessive moisture is present, then arrangements must be made to drain it away from the pavement foundation.
The bottom of the hole is trimmed such that it is flat, horizontal and free from loose material, and then, the bottom is compacted thoroughly.
The hole is then filled with a selected well graded material brought to the site.
It may consist of a material of the same quality as that of the base layer that is to be repaired or a bituminous mixed material.
The material is placed in the hole and compacted in one or more layers depending upon the thickness involved. The last layer, prior to compaction, must have an excess thickness of about 1/5 of the depth of the final layer to allow for settlement during compaction.
Compaction is continued depending on the size of the excavation, using a vibrating roller, plate compactor or a rammer, until the surfacing is level with the existing road surface.
The repair should, then be sealed, to prevent penetration of water, by spreading cut back bitumen at 1kg/m2 or 1.5kg/m2 bitumen emulsion and covering with coarse sand up to 5mm.
Repairing pothole and edge break of Herring Bone Road Brick pavement.
Bricks from damaged area is removed and placed in good condition in a pile off the roadway.
All vegetation (grass and weeds) is cleaned away from the area. New sand as necessary is added to correct the levels in the damaged area and the subgrade/subbase compacted and levelled.
The flat soling brick course is relayed, sand spread over the soling and swept into joints. A Vibrating plate or wooden tamper may be used to ensure sand penetrates into the joints between bricks until the bricks are all locked into place. Surplus sand is then cleared away.
Bricks in Herringbone pattern are placed to interlock with existing surface. To ensure a continuous bond and interlock, bricks from adjacent areas should be removed.
Sand is spread over the area and swept into joints. Vibrating plate or wooden tamper is used to assist the penetration of sand into the joints until the surface locks firmly.
Repairing depression in Herring Bone Bond Brick pavement.
All bricks are removed from the damaged area and placed in good condition in a pile off the roadway.
All vegetation (grass and weeds) is cleaned away from the area.
Sand sub-base material is removed and placed in clean stockpile area. Sub-grade is excavated, unsuitable materials rejected until sound material is located. Area of excavation should be extended, if necessary, to ensure a safe working environment. Fill and subgrade are replaced with selected materials meeting the RHD Technical Specifications requirements. These materials are compacted in 10 cm. layers until the level of the sub-base. The removed sub-base material can be used, provided it meets the specifications requirements.
New sand sub-base is replaced as necessary to correct the levels in the damaged area, and the sub-base is levelled and compacted in every 10-cm. layer.
The levels in the compacted sub-base are adjusted.
The flat soling brick course is laid, fitting closely into the existing bond. Sand is spread over the soling and swept into joints. A vibrating plate or wooden tamper may be used to ensure sand penetrate into the joints between bricks until the bricks are all locked into place.
Any surplus sand is cleared away.
Bricks are then placed in herringbone pattern to interlock with existing surface. Any bricks lying in adjacent areas are removed, if necessary, to ensure a continuous bond and interlock.
Sand is spread over the HBB layer and swept into joints. A vibrating plate or a wooden tamper is used to assist the penetration of sand into the joints until the surface locks firmly.
Finally, all excavated materials should be removed from the road.

c) Routine Maintenance of the Drainage System
The drainage system consists of side drains, cut-off-drains, drainage pipes, manholes, chutes, cascades, culverts and sub-soil drains.
The purpose of the system is to rapidly collect and conduct rain and groundwater away from the road.
Water can cause widespread and major damage to the road by weakening the pavement or foundations and erosion. The Drainage System is, therefore, the most important component of a highway or rural road.
The routine Maintenance of the drainage system is essential to preserve the road structure and running surface. More major repairs or improvements that are required would be carried out under Periodic Maintenance. Most Routine Drainage maintenance activities are ideally carried out by labour.
Routine maintenance of the Drainage System includes:
Clearing and cleaning of Ditches and Drains.
Remove all soil, high vegetation, materials and objects from the ditch that could interfere with water flow or cause an eventual blockage. These materials should be disposed of well away from roadside such that they will not impede water flow and such that they will not fall back into the drain.
On unlined ditches, a short grass cover can help stabilise the invert and sides of the drain. Therefore, a side drain is established to the correct depth and profile with grass cover and no erosion, it is advisable to only cut the grass short. This will leave the grass roots in place that will securely bind the surface to resist erosion.
Reshape/Regrade/Deepen Ditch/Drain
Remove material from the ditch to obtain the correct cross section and grade.
It is normal to adopt a trapezoidal ditch shape when using labour-based methods. A ditch template should be used to obtain the correct drain shape. Using the template, a 50 cm wide slot should be excavated to the correct ditch shape every 10 metres. The slots act as a guide for excavating the ditch to the correct shape.
In flat areas, the gradient of the ditch should be checked using ranging rods and profiles or similar methods, to ensure that water will not pond. The levels at adjacent slots should be checked using a line and level or abney level, and the level of the slot adjusted, if necessary.
Excavate all surplus material between the slots and to the correct shape with the aid of string lines stretched between the slots. If necessary, the intermediate invert levels can be checked, using a traveller sighted between the ranging rod profiles.
Material excavated from the drain must be removed and spread well clear of the drain so that it cannot wash back or fall back into the ditch. This material should not be used to reshape an earth road or shoulder. Transport the material from site, if it cannot be disposed of conveniently.
When excavating a completely new ditch, it is preferable to split the operation into two operations:
i) Cut the central rectangular shape and check it with template (invert)
ii) Cut the slopes and check with the full template (slopes)
The alignment of the drain should be set out, using string lines and pegs.
The ranging rods and profiles should be set up at the start and outfall of the ditch.
Intermediate profiles may be required on long ditches. The levels of intermediate slots can be determined, using the traveller.
Erosion control of Ditches and Drains
There are a number of different activities possible to prevent or repair erosion damage to ditches and drains.
In Bangladesh, most drain sections are in the hill areas; these are often laid at a steep gradient or on sharp bends without erosion protection along the drain or at the outfall. The following options should be considered:
i) Regrade/Realign drains
ii) Repair lining
iii) Provide/Repair Scour Protection
Where these activities are inadequate or insufficient, larger intervention should be considered as part of a Periodic Maintenance Progrmme.
i) Regrade/Realign Drain
The drain may be extended with a flat outfall to reduce the speed of the water when leaving the ditch. The gradient should ideally be between 2% and 5%.
The drain could be realigned to follow the contour lines more closely, until a location is reached where it may safely discharge.
Water cannot flow round sharp bends. The result is usually collapsed of drain sides. To overcome these:
a) Relay drain lining sections to a smooth easy curve and grout smooth any open joint or
b) Install special pre-cast concrete curved ditch sections.
ii) Repair lining
Ditches lined with masonry or other material need repair when the lining is damaged. The cause of such damage is usually settlement of the supporting soil.
The repair work is to be carried out as soon as possible as the ditch can be quickly destroyed if water can flow under or behind the lining.

The Procedure is :
Remove settled or damaged precast sections or loose stone blocks, compact the underlying soils,
Backfill with suitable, free draining granular material and compact to correct levels,
Replace the precast sections or blocks to the correct line and grade on a minimum 50mm mortar (1 cement: 4 sand) bed, grout up any open joints with mortar,
Remove all debris.
iii) Provide/Repair Scour Protection
Unlined ditches may sulphur from scour of the invert and sides. To overcome these:
Simple repairs may be achieved by filling the affected areas with soil and turfing where climatic conditions are favourable. The turves will probably need to be pegged in place to retain them in place and watered until they have established roots into the soil.
Simple scour checks may be constructed of wood or stones. Larger ones may be constructed of stone masonry, brick or concrete. They reduce the speed and hence the erosion force of the water. They also hold back the silt carried by the water flow and thus create a series of gently sloping sections of ditch separated by steps.
The scour checks must not be too high; otherwise, water will be forced onto the surrounding ground, the shoulder or the carriageway. The scour check construction should then be controlled with the aid of a template. Scour checks should not be constructed on ditches with gradients less than 4%. Too much silting would result from this that could lead to road damage.
After the basic scour check has been constructed, an apron should be built immediately downstream, either using stones or grass turves pinned to the ditch invert with wooden pegs. The apron will help resist the forces of the water flowing over the scour check. Grass sods should be placed against the upstream face of the scour check to prevent water seeping through the scour check and to encourage silting behind the scour check. The long-term objective is to establish complete grass cover over the silted scour checks to stabilise them.
More substantial erosion control measures should be designed appropriately.
Turfing, wattling and stone pitching can be used for protecting areas from erosion that are downstream from outfalls.
Clearing and cleaning culverts
In order to function properly, a culvert must retain the full opening over its complete length. In addition, the upstream approaches and the downstream area must be free of obstructions. Floating debris (tree branches, bushes etc.) carried by the water is a great danger to culverts. The debris may completely block the culvert inlet.
The following activities may be required:
If debris racks are already provided, these should be freed of all accumulated obstructions.
Sanding or silting of culverts, especially those with openings smaller than 1 meter, is a particular problem. These culverts can be cleaned by pulling a cable or rope through to which is attached any suitable object (e.g. a bucket). Alternatively, a long handled trowel and spike can be used. If the silting problem continues despite regular clearing, it may be necessary to reconstruct the culvert at a higher level or to enlarge it.
Materials and debris from the culvert must be spread or dumped where they cannot cause an obstruction to water flow, preferably on the downstream side of the culvert, well away from the watercourse.
Erosion Repair of Culverts
The following are actions that may be included under Routine Maintenance, if of a limited extent.
Where light erosion of the streambed has taken place at the culvert outlet, the following is a suitable action:
Fill eroded area with stone blocks of about 30 cm sizes to produce a rough energy dissipater. The block pitching or riprap should preferably extend beyond the eroded area. If larger stone sizes are available, these should also be used. In the dry season or when the water flow is light or non-existent, the blocks can be grouted with a concrete mix. (1 cement: 4 sand: 8 gravel).
Jute or plastic sacks, filled with soil or weak concrete (1 cement: 4 sand: 8 gravel) can also be used as an alternative to rock lining. The soil can also be mixed with 5% cement for extra stability.
Sacks should not be overfilled. Tie sacks either with soft galvanised wire or with string so that they cannot open even when roughly handled.
Lay sacks flat in layers, the sacks of one layer covering the joints of the layer below.
Cracking Repair of Culverts
Cracks in concrete or masonry are easily identified during low water or dry periods; they should be repaired as follows:
Chase out the cracks with a cold chisel and hammer. Clean the enlarged cracks with brush and water. Remove old mortar from any damaged masonry joints and clean the joints;
Where compressed air is available, deposits in cracks can be more easily removed by directing an air stream into the cracks;
Wet the crack openings before filling with a mortar (1 cement: 4 sand);
Fill cracks with mortar
Trowel the mortar smooth after the crack has been filled:
Headwall/Wing wall/Apron Repair of culverts
Where part or all of a masonry or brick headwall/Wing wall/Apron has been damaged by erosion or settlement, a repair should be carried out as soon as possible as follows:
Remove settled or damaged section of the headwall/apron,
Compact the underlying soil,
Rebuild the headwall, wing wall or apron, using similar materials to the original,
Grout up all joints with mortar (1cement: 4 sand),
When the walls are strong enough (after 2 or 3 days) back fill behind walls with soil in 10 cm layers, compacting each layer with a hand rammer to ensure it is fully compacted,
Remove all debris.
Minor Repairs of Drifts and causeways
In the case of paved crossings (masonry, brick or concrete slab), cracks should be filled with a bituminous mortar. Before filling, remove all soil and sand. Clean the crack thoroughly with water.
Potholes should be broken out down to the depth of the slab, cleaned out and filled with concrete (1 cement: 2 sand: 4 gravel), mortared stone work or bricks as appropriate.
Erosion cavities immediately upstream or downstream should be filled with large stones or rip-rap. In case of serious or recurring erosion, gabion mattresses should be laid on the bed of the watercourse with their top surface at the same level as, or slightly below the level of, the drift or causeway inverts.
Grading/Cleaning Drifts and Causeways
Water will deposit silt, sand and debris on the drift or causeway from time to time, and in or against the causeway openings. This must be removed regularly to avoid danger to traffic and the risk of erosion at the drift or causeway.
Material and debris should be removed by hand and disposed of well clear of, and downstream from the crossing.
Replace guide posts of drifts and causeways
Missing or damaged marker or guideposts on drifts or causeways must be replaced as required before the monsoon. Use steel pipe of suitable diameter and length, painted in black and white sections.
Examine the pipe sockets; remove water, sand, silt, loose mortar etc, if present. Socket depth should at least be 15 cm. Use mason's hammer and chisels to enlarge or deepen the hole if necessary.
Place the pipe in the socket and pack it, if necessary, to the correct position and height. Use a mortar (1 cement: 3 sand) to grout the space between pipe and socket wall.
Timber guideposts are not recommended as they can easily break. However, hardwood posts can be used, if properly anchored in the socket (tight fit) so they will not be washed away with the floodwaters.
Clear Manhole and underground pipes
Remove manhole cover or grating,
Before entering manhole, ensure it is free from noxious gases,
Remove all debris, sand and silt from manhole, using hand tools and buckets,
If water still cannot flow, rod from the manhole downstream of the blockage until the blockage has been removed and water flows again,
If rodding from the downstream manhole is not successful or not possible, pump water from the water-filled manhole and attempt to clear the blockage from the upstream manhole using rodding equipment.
Replace Manhole Cover or Grating of Manholes and Drainage Pipes
When a manhole cover or grating cover is damaged or broken, remove it completely, including parts that may have fallen into the manhole,
When a cover or grating is missing, search the vicinity, if it is found undamaged, replace it on the manhole. Be sure that the cover or grating is seated properly and level around the complete rim.
This will prevent unwanted movement and breakage.
If a new cover or grating has to be provided, ensure that it is the correct size and type.
If a cover or grating cannot immediately be replaced, make a temporary cover repair, using wooden planks of adequate thickness.
Clear Manhole area
Locate manhole using the drainage plan, or by trial excavations,
Remove all vegetation within a distance of 2 to 3 metres from the manhole and remove from the site,
Excavate all deposits of silt or soil covering the manhole down to a depth of at least 10 cm below the manhole cover level and for a distance of al least 1 metre from the manhole edges,
Check that the manhole cover is free of sand or silt and replace the cover,
Where necessary raise the manhole cover frame to the same level as, or just above surrounding ground level.
Clean Catchpit sump
Remove all silt and debris from the catch pit sump.

d) Routine Maintenance of Bridges
The objective is to keep the bridges in sound structural condition and safe for traffic.
Where a bridge spans a watercourse, the water must be able to flow freely at all flood levels without damaging the bridge or the waterway. Routine Maintenance of bridges include:
Cleaning/Clearing Bridges
Broom the bridge deck and sidewalks clear of all loose soil, dirt, aggregate, debris and remove these from the site.
Remove all dirt and stones, lodged between deck planking. Clear all drainage scuppers of dirt and debris so that rainwater can drain freely.
Remove all dirt and debris in joints between beams and abutment walls, and around beams bearings or supports.
Remove debris carried by floodwater or wind and lodged at piers and abutments, or at any point under the bridge.
Termites
Remove termite or white ant tunnels in the vicinity of bridges with timber components using hoes, shovels or other suitable tools. At the same time soak the ground with an approved effective chemical solution against wood-destroying agents.
Locate the termite nest, if possible. Excavate ground and soak with approved chemical. Soil poisoning can be effective but may need to be re-applied in several areas of severe termite activity.
Wood termites are difficult to exterminate completely. Most repair measures are only temporarily effective. Only pressure treated timber, which has been carefully handled after treatment, can effectively resist insect attack.
When pressure treated timber is not available, local soil soaking treatment with an approved preservative and replacement of infected timber are among the limited measures possible.
Infested timber removed from the bridge should be completely burned. Frequent inspections should be made where termites are common.
Penta-chloroprene-oil solution can be used, but it is toxic for humans and plants and is also a fire hazard. It should be handled with care and only by workmen who have received instructions regarding proper application. Care must be taken not to contaminate water supplies or watercourses.
Repair of loose/missing connectors and fixings.
The most common timber connectors are nails and bolts. These work loose under traffic and must be frequently checked. When lost or rusted, they must be replaced.
a) Bolted Joints
- The bolt shaft must fit tightly in the drilled hole. Washers must be thick enough and of ample diameter so that the timber does not crush when the nut is tightened.
b) Nailed Joints
- Nails are frequently a source of trouble. Especially when the wrong type or length is used. They work loose in timber decks and running boards; can also be drawn out by tyre suction, and damage vehicle tyres.
Examine running boards under passing traffic for movement. Extract all loose nails. Re-nail at different points (non-in old nail holes), using nails about 3 times the plank thickness. Pre-bore the planks if they tend to split when driving nails. The diameter of the bored hole should be slightly smaller than the nail diameter. For better resistance to nail withdrawal use nails with irregular shanks, for example: Annular grooved nail, spirally grooved nail.
On steel bridges, friction grip bolts do not normally work loose. Bearing bolts may work loose and should be tightened, using a torque wrench to the settings instructed by the Executive Engineer or the HQ Bridge Maintenance Engineer.
Loose rivets should be heated care-fully with an oxy-acetylene torch until blood red in colour. They should then be beaten tight using cup-sized dies that fit over the hot rivet and sledge hammers. Care must be taken not to overheat the rivet (light-yellow) or the surrounding steel.
Replace damaged planks
a) Running Boards
Extract all nails; remove defective planks and clean deck area at contact surfaces.
Use new planks of same dimensions as the planks to be replaced. New planks must be well seasoned and treated with a wood preservative. Use about 3 nails for ends of each planks and 2 nails every 25 cm along the plank. Do not drive nails near the edge of the plank: stay at least 3 cm from the edge. All nail heads must be flush with the surface of the plank.
Do not use defective timber, for example; planks with bows, crooks, twists, cups, excessive knots.
b) Deck Planks
Extract nails; lift off running boards and deck planks carefully to avoid damage to the timber stringers. Examine top surface of stringers for decay or damage (decayed stringers will need to be replaced).
Cover top of stringer with a layer of bituminous felt, place new transverse planking, properly seasoned and treated with wood preservative and nail in position. Retain ventilation/drainage gaps between planks.
When new deck planks are in position, relay old running boards, if in good condition. Otherwise replace these with new properly seasoned and treated planks. Nail into position using staggered joints.
Painting
Steel work painting by the bridge gang is generally restricted to small-scale work, for example painting of railings and occasionally steel beams. Care must be taken to ensure a satisfactory standard of workmanship.
Under no circumstances should painting be undertaken while surface are wet or if rain is expected within six hours after paint is applied.
The following steps are recommended:
a) Clean all metal surface by removing dirt dust, rust scale and loose paint. Where possible use a burner (blow torch) and then wire brush the surface to remove loose particles.
b) Apply primer coat with a brush: brush thoroughly into the steel surface ensuing that the paint covers with an even thin film with no drips.
c) Allow primer coat to dry thoroughly (24 hours minimum).
d) Apply intermediate coat (using an oil-based, metallic-based, synthetic resin or other proven high quality paint) in the same manner as for the priming coat.
e) Allow the intermediate coat ample time to dry thoroughly
f) Apply a final coat as in (d). The colour of both the intermediate and final coat should be as bright as possible for better visibility and safety.
Wood Preservation
Wood preservation of structural timber can only be thoroughly and reliably achieved by pressure impregnation where the preservative liquid is injected deep into the timber. When such treatment cannot be employed in replacement sections, apply a superficial treatment. But this method is of limited value and cannot be regarded as permanent, especially if the wood comes into contact with the soil or is used in moist conditions.
A suggested procedure for superficial treatment is as follows:
a) Put on protective clothing and protective gloves
b) Apply the wood preservative (for example, a solution of coal tar creosote and used motor-oil) with a paintbrush.
c) Ensure the preservative completely covers the wood surface and ends, and that every crack is also filled with oil. Brush in at the same time. No part should be left untreated as fungi could then easily enter.
d) Allow the first coat time to dry
e) Repeat a second application in the same manner.
f) When the surface of treated wood has been damaged by handling transport, bored-bolt-holes or sawing, apply oil treatment to the exposed surfaces as above, before installation.
g) After brushing work is completed, clean all brushes and container with solvent.
Wash away all traces of preservative where it comes into contact with the skin.
Pointing Masonry
This activity should only be carried out on masonry structures in reasonably good condition. If the structure has settled or is in danger of collapse, only complete reconstruction can be recommended.
Clean and rake out defective joints of weak mortar, soil and vegetation, using compressed air or a water spray, hammer and chisel.
At locations where the joint has to be completely renewed, the stone or brick should be eased out of place temporarily until a new mortar bed is placed.
Dampen the joint surfaces where fresh mortar has to be applied.
Mix a mortar of cement and sand as required (1 cement: 3 sand) and add only enough water to permit mortar to be applied.
Apply fresh mortar to joint, filling all space available, compacting with a suitable wooden rammer. Do not use mortar that has fallen on the ground.
Smooth joints with a suitable tool (a piece of rubber or plastic, water hose or bent reinforcing steel).
The final mortar surface should be inset slightly from the stone/brick surface to achieve a tidy finish.
In dry weather conditions mortar can dry out quickly. Prevent this by sprinkling water or joints after the mortar has set and until the mortar has completely hardened. Alternatively, cover the work area with wet jute sacks or similar.
Clean visible stone and brick surfaces that have been stained by mortar or cement water in the process of the work so that the finished work will present a neat appearance.
Do not use mortar that is greater than 30 minutes old.
Remove surplus materials and leave the site in a clean and tidy condition.
Repair barriers and safety features
Steel safety barriers, railings or parapets are damaged by vehicles from time to time. They must be repaired to continue to provide their safety function.
The damaged section should be dismantled by unbolting or using cutting equipment, if necessary.
A new section should be bolted or welded in place and painted, if necessary.
If new sections are not available, the damaged parts should be repaired in the workshop and re-installed.

e) Routine Maintenance of Traffic Control Devices
The task is to carry out all necessary Routine Maintenance activities of traffic control devices including:
Signs, reflectors, guide-posts
Kilometre-posts
Guard Rails
Pavement markings
The associated Routine Activities include:
Cleaning
This activity is limited to cleaning signs, reflectors, guidepost and kilometre-post in order to retain their effectiveness.
Clean signs, reflectors, guide posts etc. at least twice a year or more often, if necessary.
Wash the surface, using a cloth, water and detergent solution. Take care not to scratch the surface or damage the reflective paint surface.
After washing, remove all traces of detergent with a cloth and soft brush and rinse with water.
Where signs or reflectors are contaminated with bitumen or oil streaks, use kerosene for cleaning and then wash them down with water.
Re-painting
This activity involves painting or repainting:
Supporting posts for signs, rear panels of signs, kilometre-posts, guideposts, culvert marker posts, bridge marker posts.
Do not paint the front face of a sign. This work is best done in a paint shop. A reflective material surface should never be touched up with paint, as it will immediately lose its effectiveness over the repainted area
In general:
Surface to be painted are to be cleaned free of rust, dirt and all other contamination.
Use only clean soft brushes and rollers,
Painting should only be carried out during dry weather. Do not paint on a wet or damp surface or during rain,
Paints must be thoroughly mixed before application. If thinners are to be used, follow manufacturers instructions and take precautions against fire,
When reflectors are set into, or mounted on surfaces to be painted, cover these completely with paper or tape for protection during painting. Remove the paper or tape when the paint is dry to the touch.
a) Re-painting steel surfaces (sign supports, rear panels of signs etc.)
If surface paint is flaky, use a wire brush to remove all loose paint and rust, clean surface area to be repainted, using water and cloth, and then allow surface to dry thoroughly,
Use sand paper on existing paint to provide a key for the new paint. Brush the surface clean,
As soon as the surface is dry, apply a prime coat (use only paints of approved type and colour) evenly to all areas where old paint is damaged or removed.
Allow drying,
Apply the finishing coat of specified colour,
Replace lids firmly on paint cans and thoroughly clean brushes and rollers.
b) Repainting Timber Surfaces
Remove all loose paint, using a wire brush, if necessary, clean dust or dirt from surface, using a cloth or water. Allow surface to dry,
Apply a prime coat (of approved type and colour) evenly to all areas where the old paint is damaged or removed. Allow the prime coat to dry,
Apply one finishing coat of specified colour,
Reseal paint cans airtight, and thoroughly clean brushes and rollers.
c) Repainting Concrete or stone surfaces
Wash thoroughly all dirt, dust etc. from the surfaces and allow drying, applying one coat of water based, cement or latex paint of specified colour to visible surfaces,
Number or letters can be painted with the same type of paint of a specified contrasting colour.
Repainting on the Site
Correct signs facing in the wrong direction or that are tilting. Move the post to an upright position, check plumb and orientation. Re-compact soil backfill. Backfill around base of post with concrete, if necessary to improve stability, using temporary supports, if required, until concrete sets,
Replace bolts and nuts. If necessary, apply a drop of oil to the bolt or screw before tightening with wrench or screwdriver. Be sure that the drilled holes are well aligned, and that the bolt thread will not be damaged when inserting,
Replace timber support for signs, use temporary strut to support sign and remove damaged post from its foundation. Clean out foundation of loose soil. Remove any traces of insect infested timber. Replace post with similar post treated with wood preservative and attach to sign, Backfill and compact with hand rammer.
Other minor repairs are :
Setting posts deeper for extra sign stability. The depth of buried post should be at least 1/4 the length of the post where no concrete bases are provided. Signs must be fixed at the specified height.
Repairing at the workshop
Signs that cannot be repaired on the site must be repaired in the workshop or paint shop as follows:
Dismantle the sign from its post (s) carefully, retaining all nuts, bolts, screws and fittings. Transport the sign to the workshop.
When the sign has been repaired transport it to the site, reinstall it in its original location. Be sure that all bolts, nuts, screws etc are replaced and properly tightened.
Do not remove signs that have legal status; e.g. stop signs. These must be replaced.
Vegetation Control
This activity involves the control of grass, weeds, bushes and trees growing adjacent to the signposts. It is carried out at least once per year after the rainy season and often at least once more during the winter months. All these activities can be undertaken, using labour and hand tools only.
Replacing/Repairing Guard rails
Limited repairs/replacement of guardrails can be included under Routine Maintenance as follows:
Unbolt damaged guardrail panels and post and remove. Retain all undamaged bolts and nuts.
If the timber or steel post is damaged, it must be replaced,
New timber posts must be of the correct length, pressure treated, if possible and the top sawn at an angle to allow rainwater to run off. Drill the holes for bolts,
Excavate the posthole wide enough to allow use of the tamper to compact the soil around the post. Alternatively, an excavation can be hand bored using a hand auger for the lower half of the excavation;
Place the post in the excavation; check position, height and alignment. The post must be kept vertical and in alignment during back filling;
Place the backfill in layers not exceeding 10 cm loose soil. Compact the loose soil with a hand rammer, adding water, if necessary, until no further compaction is attainable. Repeat until the backfill is level with the ground surface;
Where steel posts are used, they should be cast into a concrete footing, allow the concrete to set;
Assemble the new guardrails, taking care that the section overlaps are installed exactly as before (the joint overlaps must correspond with the direction of the traffic in the nearest lanes);
Tighten all bolts and nuts
Pavement Marking
Pavement marking is usually limited to repainting existing worn centrelines and shoulder edge lines in order to restore them to their intended colour and outline. Markings are also renewed after major resealing work under the periodic maintenance Programme works.
No painting work should start until all warning and speed reduction signs and flagmen are in position. Ensure the workforce can work safely;
The road surface must be dry;
Clean existing markings, where required, using a stiff brush. No dirt, dust or other contamination should be left on the surface to be painted;
Apply the paint sparingly after thoroughly mixing and adjusting the stencil to the line edges, Thick paint lines tend to crack on drying. Paint only within the limits of the existing markings, otherwise the edges will look ragged. Do not leave open paint cans unattended. If a spill occurs, clean pavement surface immediately;
The road marking paint should dry in 10-15 minutes (depending on paint type and weather conditions). Do not remove any cones or allow traffic to run over the freshly painted lines before the paint is dry enough for traffic;
Ensure that the warning cones are correctly spaced and located along the line being painted. Cones displaced by traffic should be reset in position without delay;
Observe the progress of the work and move the flagmen and warning signs as soon as the paint has dried over a sufficiently long section of road.
The work must be organised so that all painted areas will be traffic dry by the time cones and signs have to be removed at the end of the day's work;
Remove any unwanted markings, using blowlamp and scraper. Do not overheat the bitumen road surface. Do not use black paint to try to cover up mistakes.
Road line- marking can also be carried out; using mechanical equipment, such as, hand or self propelled line-marking machines
Replacing Signs
Remove damaged sign, supporting post and, if necessary, the foundation block;
Locate replacement sing as close as possible to the old one in the correct location and orientation;
Excavate the new post foundation and trim the foundation signs vertical. The foundation for a single post standard sign should be at least 30 cm x 30 cm wide and 50 cm deep if a concrete backfill is used. The foundation must be at least 90 cm deep for soil backfill.
Assemble replacement sign on new post, tightening all bolts, nuts and screws;
For concrete backfill, prepare a mix (1cement: 3 sand: 6 aggregate), adding only enough water to obtain a workable mix;
Erect new post in the middle of the foundation. Use temporary struts to hold the post in position and check for alignment and orientation;
The sign must be turned slightly away from the road so the minor reflection (caused by the headlights at night) is avoided,
Pour concrete and compact with a hand rammer. Alternatively, place and compact soil in 10 cm layers;
Smooth the concrete surface to a slight slope downwards from the post to the edge of the foundation;
Remove damaged sign, surplus soil, concrete and all debris from the site. Do not leave any part of the old sign exposed above ground level;
Reinstate the area of the old sing.
Repairing or Relocating Kilometre post
Kilometre-Post are necessary to inform road users of their location and to identify and locate maintenance works.
They are normally relocated in a simple excavation that is then back filled with soil. The depth of the excavation depends on the size and shape of the kilometre -post.
The location is normally determined and staked by the road surveyor.
Some kilometre-posts may be required to be more stable, and hence, may be set in a concrete foundation.
The kilometre-post should be set as far back from the road edge as possible or as far as the shoulder width will allow, and yet be visible to road users. It should not be placed on the edge of an embankment or road ditch where tilting or setting is likely to occur.
a) Kilometre-Post with concrete foundation
When relocating the existing kilometre-post, remove it from its concrete foundation. Backfill the excavation and compact until the surface is level with the surrounding ground;
Transport new or existing kilometre-post to its new location fixed by the surveyor. Two takes and a line should be used to set out the location and face of the kilometre-post.
Excavate the new foundation to allow for 25 cm concrete around the perimeter and 10 m under the base. The sides should be vertical and the base should be level.
Place a 10 cm dry mix concrete (1cement: 3 sand: 6 aggregate) in the foundation and compact;
Place kilometre-post on the dry concrete bed; check its level and orientation. Mix just sufficient water to make the rest of the concrete workable and backfill the foundation with the concrete until it is slightly above the ground level. Trowel the concrete surface smooth with a slight slope downwards from the post to the edge of the concrete.
If necessary, repaint the kilometre-post.
Remove excess soil, concrete and debris from the site.
b) Kilometre-Post without concrete foundation
Excavate the foundation at the location fixed by the surveyor and deep enough for stability (usually half the depth of the kilometre-post) and wide enough to allow for compaction of the backfill with available hand rammers;
Level off foundation base and compact with the hand rammer;
Centre the kilometre post in the foundation excavation; check plumb and correct orientation;
Backfill around the kilometre-post base in loose layers not exceeding 10cm, compact with the hand rammer;
As soon as the compacted backfill has reached a level slightly higher than the surrounding ground, smooth off the soil surface and remove surplus soil away from the site.
2. Periodic Maintenance Works
Periodic Maintenance Works are normally large-scale preventive maintenance works, which go beyond the limits of routine maintenance works of bituminous Road Surface (maximum 150 potholes repair of 30cmx30cmx10cm size in any one kilometre, edge repair of 100 metres in any kilometre and crack sealing of maximum 150 m2 in any one kilometre). These are costly operations identified and determined on the basis of Road Condition Survey, Traffic Survey, Roughness Survey and the economic analysis obtained using HDM4.
The programme analysis tool incorporated in HDM-4 is the analysis for doing the yearly maintenance programme or for the multi-year rolling programme. It is used for easy analysis of the whole road network for identifying the candidate road sections for the maintenance for a particular budget period.
For the constraint budget, the economic criteria for selecting the candidate road are the maximisation of NPV/cost.
RHD has prepared the yearly maintenance programme for the financial year 200-2001 by doing this programme analysis for the bituminous roads of the whole road network.
The Periodic Maintenance Works for bituminous roads selected by HDM-4 analysis include:
Preparatory Patching : Patching potholes prior to undertaking the treatment like DBST, overlay and carpeting.
Preparatory Edge Repair : Restoration of pavement edges that have been damaged by vehicles leaving the road to drive onto the shoulder.
Manual seal coat : Traditional seal coat treatment (15 mm thick) used on the more lightly trafficked roads. This has a 2-3 years life.
Double Bituminous surface : Applying two layers of surface treatment on the prepared road
Dressing (DBSD) surface of the specified specification. The total thickness has been specified as 25mm. This is applied in medium to highly trafficked road. Life expectancy is 4 to 7 years
Bituminous Carpeting : This is a 37 mm thick manual overlay used in low trafficked
roads in place of overlay. Life expectancy is 4 to 8 years
Overlay : Machine laid premixed bituminous asphalt concrete overlay 50 mm thick used in medium to highly trafficked roads. Carefully controlled overlay may be applied in response to badly damaged road or road with higher roughness so as to obtain a predefined roughness level (2-2.5 IRI). Life expectancy is 5 to 10 years.
How Routine and Periodic Maintenance Works are taken up:
The annual maintenance programme for Routine & Periodic Maintenance Works is approved by ACE zones on the basis of allocation of fund by MoC/CE in the Revenue head for such works. The works included in the approved programme for different roads are selected according to HDM-4 analysis on the basis of maximisation of NPV/cost.
The works are taken up as per approved programme and budget grant for different zones. The contractors may be selected by the Planning and Maintenance using for periodic maintenance works depending on how CE, RHD approves it. But the works are executed under the supervision of zonal officers.
 
References :

Bangladesh Routine Road Maintenance Handbook

HDM-4

Road Condition Survey Manual

Traffic Survey Manual

Roughness Survey

Geometric Standards of RHD

Traffic Signs Manual

OP/ZF/1.1 - Annual Budget Request and Survey

OP/ZF/1.4 - Preparation of Annual Work Programme
 
Procedure Flowchart :

The procedure flowchart for this procedure is detailed below -
 


 


 

 

For duties associated with each grade of personnel see

 

Updated on : 1/12/2003

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