Grade changes shall not be too frequent as to cause kinks and visual discontinuities in the profile. Desirably there should be no change in grade within a distance of m. Decks of small cross drainage structure i. The vertical alignment shall be coordinated with the horizontal alignment as indicated in Section 2. Ruling gradient shall be adopted as far as possible. Limiting gradients shall be adopted only in very difficult situations and for short lengths.
In cut-sections, minimum gradient for drainage considerations is 0. Long sweeping vertical curves shall be provided at all grade changes. Summit curves and Valley curves shall be designed as square parabolas. The length of the vertical curve is controlled by sight distance requirements, but desirably curves with longer length shall be provided from aesthetic considerations.
The minimum grade change requiring vertical curve and the minimum length of vertical curve shall be as given in Table 2. The overall appearance of an expressway can be enhanced considerably by judicious combination of the horizontal and vertical alignments.
Plan and profile of the road shall not be designed independently but in unison, so as to produce an appropriate three-dimensional effect. Proper co-ordination in this respect will ensure safety, avoid visual discontinuities and contribute to overall aesthetics. Vertical curvature superimposed upon horizontal curvature gives a pleasing effect. As such the vertical and horizontal curves shall coincide as far as possible and their length shall be more or less equal.
If this is difficult for any reason, the horizontal curve shall be somewhat longer than the vertical curve. Short vertical curve superimposed on long horizontal curve and vice versa gives distorted appearance and shall be avoided.
The designer shall check profile design in long continuous plots to help avoid a roller-coaster profile. Wherever a cross road is proposed to be taken below the Project Expressway, minimum clearances at underpasses shall be as follows:. However, these will not be a substitute for normal requirements of pedestrian and cattle crossings as per para 2. Wherever any structure is provided over the Project Expressway; the minimum clearances shall be as follows:.
Full roadway width for 8-lane carriageway or wider where specified in Schedule-B of the Concession Agreement shall be carried through the overpass structure. The abutments and piers shall be provided with suitable protection against collision of vehicles. Crash barriers shall be provided on abutment side and on sides of piers for this purpose. The ends of crash barriers shall be turned away from the line of approaching traffic. The span arrangement for the overpass structure shall be as specified in Schedule-B of the Concession Agreement.
A minimum 5. Project Expressway shall be designed for fast motorized traffic with full control of access. Access to the Expressway shall be provided with grade separators at location of intersections. The locations of individual interchanges are determined primarily to reduce detour considering regional network and nearness to places of importance. Location of interchange is guided by the following situations:.
The interchanges shall be provided at the locations specified in Schedule-B of the Concession Agreement. These shall be provided outside the fencing. The location, length, other details and specifications of connecting roads, to be constructed by the Concessionaire shall be specified in Schedule-B of the Concession Agreement. The width of the connecting road shall be 7.
The construction and maintenance of connecting roads shall be part of the Project Expressway. The type, location, length, number and the openings required and approach gradients for various grade separated structures shall be as specified in Schedule-B of the Concession Agreement.
The approach gradient to the grade separated structure shall not be steeper than 2. The structure may be either an underpass or an overpass depending upon the nature of terrain, vertical profile of road, availability of adequate right of way, etc.
Unless otherwise specified in Schedule-B of the Concession Agreement, the Project Expressway shall be carried at the existing level and the entire cost involved in raising or lowering the road would be included in the cost of the Project Expressway.
Decision whether the cross road or the Project Expressway will be carried at the existing level will be taken at the time of preparing the feasibility report and would be based on considerations of drainage, land acquisition, provision of ramps for the grade separated facility, height of embankment and project economy etc.
In built up areas, the Project Expressway shall be elevated on via duct as specified in Schedule-B of the Concession Agreement. The crossing facilities shall be provided such that the pedestrians do not have to walk for more than m to reach the crossing point. These shall be provided as specified in Schedule-B of the Concession Agreement. Median openings with detachable barrier shall be provided for traffic management for maintenance works and vehicles involved in accidents.
Such barriers shall be located at ends of interchanges and rest areas. It is desirable to provide median openings with detachable barriers at about 5 km spacing. Maintenance and emergency crossovers generally should The fencing shall be of type and design given in Section of this Manual.
Typical cross sections of Project Expressway are given in Figs. Typical cross sections for culverts, bridges, and grade separated structures are given in Section-6 of this Manual. A clear zone is the unobstructed traversable area provided beyond the edge of the through carriageway for the recovery of errant vehicles. Embankment slopes of 1V:4H or flatter are recoverable slopes and if it is not feasible to provide the suggested clear-zone distance from the edge of the carriageway, a crash barrier should form part of the clear-zone distance.
The concept is illustrated in Fig. The design service volume per day will depend on the peak hour flow and will be as specified in Table 2. These shall be specified in Schedule-B of the Concession Agreement. The access from the Project Expressway to the cross roads in case of Grade Separators shall be through the nearest interchange. Gradient for approaches shall not be steeper than 2. Design of structures shall conform to Section-6 of this Manual. Minimum length of viaduct required to be provided shall be specified in Schedule-B of the Concessionaire Agreement.
This requires the consideration of tolling system which considers a barrier system as well as toll booths on the interchange ramps. This requires provision of appropriate deceleration and acceleration lanes and operating speed limitations in the interchange areas. For this category, since both the intersecting routes are toll roads under closed system, toll booths on ramps are not required. The system needs to cater for high speed operation.
The toll collection arrangements need to be considered on integrated basis between the two involved expressway stretches. The modalities need to be suitably addressed. Generally, Trumpet-type and T-type Interchanges are the preferred configuration. The advantages are;. System interchanges are to handle high volume of traffic. The connecting ramps can be directional, semi-directional and large radius loops as well.
The aspect of toll sharing between adjacent concessionaires shall be integrated. The basic forms may comprise of three legs or four legs. For Three Leg Interchanges, the T-type configuration would require larger loops and semi directional ramps of larger radius based on traffic volumes. This may also require catering for frontage road. For Four Leg Interchanges, the forms may be Diamond, clover leafs directional and semi directional interchanges and composite interchanges requiring combinations of straight, curved or with loops and weaving.
These configurations generally require multi-level structures. Ramps are provided at interchanges for desired turning movements. Based on movement requirements, the connecting ramps may be classified as Direct, Semi-direct and Loop ramps Fig. Interchange spacing is based upon demand for access from the important cross roads, adequate distance to provide for signing and weaving and permit sufficient lengths of speed change lanes for respective adjacent interchange to operate safely and efficiently For expressways, a spacing of 3 km is absolute minimum from deceleration, weaving and acceleration consideration.
For spacing less than 3 km, both the interchange shall be considered as a combined one. For expressways, a spacing of km is desirable. The ramp shall have two lanes. The ramp cross-section showing carriageway width and shoulder both paved and earthen is given in Fig. The width of paved and earthen shoulders considered here are for interchange ramp design only.
Applicable extra wide carriageway shall be provided, as needed from ramp radius consideration. Drivers exiting an interchange are required to reduce speed to meet with toll payment where such a scheme exists.
Drivers entering an expressway from a ramp accelerate until the adjacent through lane speed is reached. For safety, expressway exits should be located on tangent sections, wherever possible to provide maximum sight distance and optimum traffic manoeuverability operation. The following recommendations should be considered from safety aspect. Typical requirements of Acceleration length and Deceleration length and speed change length adjustment factors are presented in Table 3.
For intermediate values of design speed, suitable rate of taper be adopted. The Concessionaire shall submit the details of the ground surveys, traffic data, traffic forecast, design and drawings of the intersections and interchanges showing all safety features to the Independent Engineer for review and comments, if any. The design and construction of the road in embankment and in cutting shall be carried out in accordance with Section of MORTH Specifications and the requirements, and standards and specifications given in this Section.
This Section also covers specifications for subgrade and earthen shoulders. The final centre line of the road and the road levels shall be fixed duly considering all the relevant factors covering structural soundness, safety and functional requirements as per relevant IRC Codes and provisions of this Manual. In rolling terrain where fill material is available from cuttings, the embankment could be sufficiently raised to permit construction of underpasses without lowering the level of cross roads.
The principles given in para 4. The height of the embankment shall be measured with respect to the finished road levels. The following principles shall be kept in view while fixing the road level:. To attain a natural appearance along the roadside, the side slopes should be as flat as possible and rounded.
The slopes should be designed from stability considerations and to provide a reasonable opportunity for a driver to recover control of an errant vehicle. If the right of way or other constraints make it impractical to provide recoverable slopes, it would be necessary to provide a safety barrier. Embankment slopes 1V:4H or flatter are recoverable slopes. Fixed obstacles such as culvert headwalls shall not extend above the fill slope within the clear zone distance.
Embankment slopes between 1V:3H and 1 V:4H are traversable but non-recoverable and a clear run-out area at the base is desirable as shown in Fig. Embankment with height 6. Drainage arrangement shall be provided as per Section-6 of this Manual.
Where pond ash is used for embankment construction in pursuance of the instructions of the Ministry of Environment and Forests or otherwise, the embankment shall be designed and constructed in accordance with IRC:SP The road level shall be fixed, keeping in view the provisions of relevant IRC Codes, and the side slopes of the cut section shall be governed by the type of soil met with. Generally, the side slopes shall be as given in Table 4. The slopes should be evaluated with regard to soil stability and potential crash severity.
Desirably, the toe of the rock-cut slope should be located beyond the minimum lateral distance from the edge of the carriageway needed by the driver of an errant vehicle to either regain control or to slow down the vehicle. The Concessionaire shall carry out necessary soil surveys, and field and laboratory investigations for selecting appropriate borrow pits, identifying and treating problematic ground locations, if any, and for finalizing structural features and design of the embankment and cut sections and establishing improved ground properties.
A report on the soil investigations shall be furnished along with the design to the Independent Engineer. Soil investigations and tests shall be carried out in accordance with the requirements specified in IRC:SP and information regarding depth of water table, seepage flow, presence of any weak, unstable or problematic strata. The Concessionaire shall prepare the design report with all relevant details including the following:. The design and construction of pavement shall be carried out in accordance with the criteria, standards and specifications given in this Section.
Where alternative specifications or materials are proposed to bring in innovation in design etc. The design of pavement shall take into account all relevant factors for assuring reliable performance, surface characteristics and shall satisfy the specified minimum performance requirements. The Concessionaire shall undertake the necessary soil, material and pavement investigations and traffic volume and axle load studies in accordance with the good industry practice for preparing detailed designs.
Where problematic conditions such as expansive soils, swamps or marshes, flooding, poor drainage, frost susceptible areas etc. Such requirements shall be as specified in Schedule-B of the Concession Agreement. The pavement shall be designed to ensure the specified performance for the projected traffic needs, climate and type of soils in the given area. The Concessionaire is expected to use a design procedure that is appropriate to produce a cost-effective structure meeting the performance requirements and long term durability.
Continuously Reinforced Concrete Pavements CRCP shall be designed as per any recognised international guidelines which shall be subject to approval by the Independent Engineer. The design traffic shall be estimated in terms of cumulative number of standard axles kg to be carried by the pavement during the design period. Estimate of the initial daily average traffic flow shall be based on determination of diverted traffic, induced and development traffic.
Any likely change in traffic due to future development plans, land use, shall be duly considered in estimating the design traffic.
Traffic growth rate shall be estimated for each category of commercial vehicles to be considered for design of pavement. For traffic projections, the procedure outlined in IRC: may be followed. The Concessionaire shall adopt a realistic value of the rate of traffic growth, provided that annual rate of growth of commercial vehicles shall not be adopted less than 5 percent.
Where strengthening of pavement is needed, a detailed pavement condition survey and evaluation shall be carried out to determine. Necessary corrective measures to treat the identified deficiency shall be taken with strengthening of the pavement. The thickness and composition of the paved shoulder and edge strip shall be same as that of the main carriageway.
The Concessionaire shall prepare a design report and submit it to the Independent Engineer for review and comments. The overall width of structures shall be such that the outer face of left crash barrier on the structure is in line with outer edge of earthen shoulder and inside crash barrier is located at a clear distance of 0.
These are applicable both for depressed median and flush type median on The Concessionaire may choose any type of structure and structure system commensurate with safety, serviceability and durability requirements. The general guidelines as below shall be followed:. The Concessionaire shall be responsible for the safe, workable design and methodology for all temporary or permanent forms, staging and centering required for supporting and forming the concrete of shape, dimensions and surface finish as shown on the drawings Refer IRC Adequate foundation for the staging shall be ensured.
Redundancy in support system shall also be ensured by providing diagonals and additional members. Designs, drawings and methodology proposed by the Concessionaire in the use of special temporary and enabling works like Launching Girders, Cantilever Construction Equipment, Tall Formwork, Shoring for Earth Retention, Lifting and Handling Equipments and the like shall be submitted to the Independent Engineer IE for his review and comments, if any.
The Concessionaire shall be fully responsible for the design and structural adequacy of all temporary and enabling works. Review by the IE shall not relieve the Concessionaire of this responsibility. All bearings shall be easily accessible for inspection, maintenance and replacement. Suitable permanent arrangements shall be made for inspection of bearings from bridge deck. Spherical bearings shall conform to the requirements of BS and materials of such bearings may conform to the relevant BIS codes nearest to the specifications given in BS The drawing of bearings shall include the layout plan showing exact location on top of pier and abutment cap and the type of bearings i.
The bearing should cater for rotation and movement in both longitudinal and lateral direction. The Concessionaire shall submit detailed specifications, designs and drawings including installation drawings and maintenance manual incorporating the replacement procedure for review of the Independent Engineer.
The bearings shall be of such type which do not require replacement for at least 50 years for major bridges, vehicular underpasses and rail road structures and 25 years for other structures. The QAP shall give the full details of the process of quality control, raw material testing, various stages of manufacture, testing of bearing components as well as testing of complete bearing in conformity with relevant part of IRC, prior to the commencement of manufacture of the bearings.
The Concessionaire shall submit a certificate of confirmation regarding quality control measures taken during manufacture of the bearings and the material conforming to the prescribed standards and specifications. Full lot of bearings of the sample found to have inferior specifications to those certified by the manufacturer or to have major discrepancy in material specifications or which fail to meet the acceptance criteria, shall be rejected.
Reinforced earth retaining structures shall not be provided near water bodies. Local and global stability of the structure shall be ensured. Guidelines for drainage given in Section-9 of this Manual shall be adopted. The sketches of concrete crash barriers extracted from IRC:5 are given in Figs. Future widening of structures shall be adopted by suitable method so that there is seamless travel path. Suitable markings and signages shall be placed for guidance of traffic.
It will be better if the new structure is stitched with the existing structure by dismantling the crash barrier on the existing structure. Where stitching is not possible, new structure may be added abutting the old structure, crash barrier dismantled and longitudinal joint provided between the old and widened structure.
The edge strips of the two structures may be suitably marked to prohibit vehicles travelling on this portion. Any other innovative method of widening the old structure may be adopted so that safety of structure and traffic is not compromised. The Concessionaire shall furnish the design report, including the following, to the Independent Engineer for his review and comments, if any.
Expressway shall be constructed in tunnel either to carry the alignment under or through a natural obstacle or to minimize the impact on the community under conditions such as:. Planning and design of tunnel shall be based on various conditions along the expressway alignment including the topography, geology, meteorology, environment, locations and traffic volumes and shall generally conform to provisions of IRC:SP and this Manual.
Wherever tunnel is required to be provided, its location, length and number of lanes shall be indicated in Schedule-B of the Concession Agreement. A tunnel shall have the same geometric standards as on the expressway carriageway outside the tunnel except as specified in this Section.
Shape of tunnel cross section shall be commensurate with the methodology of construction, e. The tunnel shall cater for carriageway, paved shoulder, edge strip as on the adjoining carriageways outside the tunnel, and space to be provided for ventilation ducts, escape footway, emergency lay-bye where necessary, lighting, drainage, fire and other services. The tunnel shall have a minimum vertical clearance of 5. Vertical clearance over footway shall be 3. Additional vertical clearance shall be provided for accommodating tunnel ventilation and lighting fixtures.
Tunnels shall have paved shoulder of 3. In case of tunnels having more than m length, provision shall be made for 10 m long and 1. Proper transitions, line of sight and informatory signs shall be ensured for such lay-bye. Typical tunnel cross sections for unidirectional traffic conditions for three-lane carriageway configurations are given in Fig. A typical layout of lay-bye is shown in Fig.
The clear distance between the twin tubes shall be kept depending upon the type of strata and structural stability of the tunnel. The cross passage shall be at an angle of 30 degrees with the direction of flow as shown in Fig. The cross passage shall have provision for one traffic lane, edge strip of 0.
In normal conditions, the cross passage shall be barricaded. The vertical gradient shall not be more than 3 percent for tunnels of length more than m. In short tunnels, the gradient may be limited to 6 percent. However, in such cases the ventilation system should be designed to take effect of gradient and possible incidence of fire. The horizontal alignment shall be straight as far as practicable. However, the straight stretch shall not be more than m to avoid the effect of monotony and induction of an unconscious increase in speed.
Similarly, the last few metres of the tunnel shall have gentle curve. The curves, if provided, shall be gentle and meet the minimum radius requirements for design speed of the tunnel. In case of twin tunnel, the crossing of Tunnel wall lining shall be of white colour with high luminous reflectance. Tunnel portals should, apart from providing protection at entry and exit, convey drivers about the presence of the tunnel, reduce the luminance of facing walls and be in harmony with the surrounding environment from aesthetics considerations.
In order to make a realistic geotechnical and geophysical assessment of the ground through which the tunnel is to pass and detailed mapping of surface geology of the tunnel area necessary for the planning and design of alignment and portal locations, shape of tunnel, tunnel supporting systems, minimum distance to be kept between two tunnels, independent geotechnical investigations should be carried in accordance with the provisions of Section-3 of IRC:SP Assessment of applicable loads shall be based on structural properties of the ground likely to be met during tunneling as arrived from detailed geo-technical investigations.
The design shall cater to the most adverse combination of load conditions including only those loads which have reasonable probability of simultaneous occurring with due consideration for the methodology of construction particularly in case of soft strata and soils.
The design shall be checked for loading conditions during the stages of construction, operation and maintenance. Structural design of tunnel system passing through soft strata and soils may be carried out by suitable national or international standards, specialist literature and best engineering practices.
The drains shall be located below the walkways meant for the pedestrians and maintenance personnel. The carriageway shall have suitable camber to facilitate drainage into the side drains. In case of bi-directional tunnel, the camber shall be from the centre outwards and in case of uni-directional tunnel from high speed lane towards low speed lane.
The vertical profile shall facilitate self draining of tunnel. In case this is not feasible, detailed draining system shall be designed by providing sumps and combination of self draining and pumping arrangements. The black-topped road surface inside tunnel, generally constructed on rocky subgrade, gets damaged due to seepage water and creates severe problem for surface drainage.
Hence the pavement inside the tunnel and in approach cuts shall be of high performance pavement concrete. Waterproofing in the form of tunnel lining such as cast in situ concrete shall be provided for structural protection from surrounding weathering effects as well as operational considerations.
To prevent water leaks inside the tunnel, water proof sheet at least 0. Natural ventilation may be sufficient for tunnels of length up to m. However for tunnels of length more than m natural ventilation system should be used only after thorough evaluation of reliance on natural ventilation especially with reference to effects of meteorological and operating conditions.
Detailed design of ventilation shall be carried out as per Section-7 of IRC:SP keeping in view the length, shape, size, tunnel environs and complexion of the likely traffic for which tunnel has been designed. Provisions shall be made for installation of tunnel furnishing such as sign boards, fire fighting arrangements, cable trays for telephone and power lines etc.
Signage system shall be complemented by providing traffic lights above each lane at the entry portal end and inside. The markings shall be done by means of self propelled machine which has a satisfactory cut-off capable of applying broken line automatically. Tunnel emergency facilities to mitigate damage in the event of incidence of fire or any other accident in the tunnel shall be provided in conformity with the standards for installation of emergency facilities according to the classification based on traffic volume and length of tunnel as shown in Fig.
Types of details of emergency facilities to be provided are categorized as Information and Alarm Equipment, Fire Extinguishing Equipment, Escape and Guidance Facilities and other equipment. Requirements are as under:. It shall be ensured that all applicable rules and regulations relating to the construction of tunnels are duly complied with in strict conformity with the spirit and body of such regulations.
A project safety plan PSP relevant to particular site shall be prepared by the Concessionaire and got approved from the competent authority. The PSP shall address all site-specific issues and take all the identified risk elements.
During all operations connected with the construction of tunnels, appropriate safety precautions shall be taken through the implementation of the PSP.
An emergency management plan shall be part of the approved Project Safety Plan which shall be well communicated to all working personnel and prominently displayed at site.
Emergency Research Measures should be drawn up to take care of various possible contingencies. All materials to be used in works shall be in conformity with the requirements laid down for relevant item in MORTH Specifications. Proprietary products proposed to be used shall be proven by use in comparable international road and bridge projects, and shall be supported with authenticated licensing arrangement with the manufacturer. The design and construction of surface and subsurface drains for road drainage and drainage for structures shall be carried out in accordance with the requirement of this Section.
In road sections in cuttings and at underpasses where it may not be possible to drain out the water using gravity flow, vertical drains may be provided and if necessary, arrangement for pumping shall also be made. The selection of type of roadside drains shall be based on the magnitude and duration of flow.
The roadside drains shall be designed on the principles of flow in open channel. The road side drains shall not pose any danger to traffic, slopes of cuttings, embankment, pavement or structures. As far as possible, longitudinal slope shall not be less than 0.
Permissible non-erodible flow velocity for corresponding earth surface as mentioned in Clause 9. The side slopes of the unlined drains shall be as flat as possible and shall not be steeper than 2H:1V. In case of depressed median, longitudinal drain lined or unlined shall be provided to drain off rain water. The drain should have adequate longitudinal slope to the nearest culvert to drain off transversely.
In superelevated sections, the longitudinal drain shall be designed to take the discharge from one side carriageway also. The flush median shall be paved and provided with camber for drainage across the pavement. In superelevated sections, combination of covered longitudinal and cross drains shall be provided. In embankments with height more than 6 m and approaches to bridges, special arrangement for protection of embankment slopes shall be essential in order to ensure that embankment slopes maintain their shape during the monsoon season.
In this respect, directions contained in Clause 7 of IRC:SP may be followed as appropriate for the climatic conditions of the area of the Project Expressway. The drainage system and slope protection shall be kept well maintained at all times.
The chute drains and drains at toe of the embankment shall be of Plain Cement Concrete M15 grade , over bedding in Cement Concrete M Suitable catch water drains shall be provided on the hill slope above cutting to collect and remove surface water run-off from upper reaches. These drains shall be of trapezoidal shape with stone lining pointed with cement sand mortar.
The catch water drains shall be designed to carry the intercepted water to the nearest culvert or natural drainage channel. Where required, lined chutes shall be provided to lead the discharge to the catch pit of culvert or to a natural drainage channel. Perforated pipes and un-perforated pipes shall meet the requirements of Clause Sub-surface drains outside the road pavement shall be sealed at the top to avoid percolation of surface water into these drains.
Trench excavation, laying of pipe, backfilling, and use of geo-synthetics shall conform to the requirements of Clause The drain outlet shall be a free outlet and shall be provided as per Clause Design of subsurface drainage shall be based on a rational basis.
The length and location of these drainage spouts should be such that the water is not discharged on any bridge element. The bridges particularly those in high rainfall area shall preferably be built in longitudinal gradient with suitably designed cross drains at abutment locations to facilitate proper drainage.
Effective drainage shall be provided both longitudinally and transversely. The transverse drainage shall be secured by means of suitable camber in the roadway surface. Longitudinal drainage shall be secured by means of scuppers, inlets, or other suitable means of sufficient size and numbers to drain the run-off efficiently. Efficient drainage of the deck structure shall be ensured by providing a suitably designed drainage arrangement consisting of drainage spouts connected to horizontal and vertical pipe system such that the water from the structure does not fall on the road, does not stagnate over the road or at entry and exit points of grade separated structure and is discharged into the draining system of the area.
Care must be taken that the pipes are taken down in such a way that they are aesthetically pleasing. Typically, water spouts are provided at the kerbs at the rate of one number per 12 sqm of the surface in level portions and one number per 15 sqm of the surface area on gradients. Water spouts are connected to runner pipe of suitable diameter minimum mm on either side of roadway and taken down by downtake pipes at pier and abutment locations.
Drainage fixtures and downspouts shall be of rigid, corrosion resistant material not less than mm as the least dimension and shall be provided with suitable cleanout fixtures.
The arrangement of floor drains shall be such as to prevent the splashing discharge of drainage water against any portion of the structure. Overhanging portions of concrete floors shall be provided with drip moulds. Catch water drains are necessary at the ends of viaduct portion so that water coming from grade separated structure does not over saturate and affect the earthen embankment. Similar catch water drains should be provided at the end of gradient so that water coming from the structure is properly let out to the nearest drain.
An integrated drainage plan for the water coming from the deck of structures, local catchment area of the project and all other sources should be prepared so that no water falls on any surface of the structures, or remain standing or flowing over the level roads. All the water is collected through sumps and finally discharged into the local drainage system i. The rainwater from the deck of the structures usually does not flow transversely but flows on the high gradient slopes of the road or approaches and is collected in the valley curve portion.
As such attention is to be paid to get this large quantity of water drained out fast without accumulating there causing problems for traffic flow resulting in traffic jams. The draining out systems should be designed with greater margins so as to avoid this problem, at least for grade separators, inside the cities or inhabited areas. For the existing drains, canals and waterways, to be over passed by the expressway, draining provisions shall be maintained and the effects of prolonged heavy rainfall must be catered for.
Special attention shall be paid to the drainage channels carrying industrial waste and effluent in particular to those draining chloride contaminated effluents which are detrimental to the RCC structures. Adequate care shall be taken while crossing irrigation canals to prevent contamination of the flow in the canal by spillage from the expressway. When expressway runs parallel to existing channels, adequate measures shall be taken in the form of bank protection and channel alignment to avoid water build up or stagnation against the expressway slope endangering the pavement drainage.
The drainage channels at the toe of the expressway may have to be adequately protected or reshaped for discharge into these channels. Where the discharge from road drainage is not permitted, separate cross drainage structures are to be provided on both sides of such channels.
Guidance may be taken from IRC for treatment of! The Concessionaire shall carry out proper surveys and investigations for detailed design of the drainage system. The proposal for drainage system supported with survey investigation report and detailed design report shall be submitted to the Independent Engineer for review and comments, if any.
Traffic Control Devices, Road Safety Devices and Road Side Furniture shall comprise of road signs, road markings, object markers, hazard markers, studs, delineators, attenuators, safety barriers, boundary fences, boundary stones, kilometre stones, etc.
The road signs on expressways are required to provide adequate information on lane driving, advance information to exit, location of facilities for road users and also for emergency need for vehicles, Road signs shall be provided as per IRC and Section of MORTH Specifications.
Clustering and proliferation of road signs shall be avoided for enhancing their effectiveness. For direction informatory signs, it shall be white lettering, border and arrows on blue background. In case of facility signs, black symbol shall be displayed within White Square in blue background.
The font type shall be as per Table Size of letters shall be such that these are ligible and visible at design speeds. The size of letters for Advance Direction, Flag type direction, reassurance, place identification and Gantry mounted signs for various approach speeds shall be as per Table For supplementary plates attached with facility signs, regulatory signs or cautionary signs, the letter size shall be mm.
The sheeting for different type of signs can be chosen based on the selection guidance provided in IRC depending upon the situation encountered by road users in viewing the signs. Class B micro prismatic sheeting can be used for delineator posts. Wherever the Expressway alignment is on a curve, there shall be advance cautionary signs for sharp curves depending on whether it is on left or right and chevron signs rectangular in shape with yellow background and black arrow at the outer edge of the curve.
The size of chevron shall be as per IRC Required prohibitory sign shall be placed prohibiting the entry of certain types of vehicles into the Expressway.
Locations and size of overhead signs shall be specified in Schedule-B of the Concession Agreement. The following conditions may be considered while deciding about the locations of overhead signs:. Signs shall be mounted on gantries, cantilevers, and butterfly or on over bridges with vertical clearances as applicable for vehicular operations. The sign supports shall be provided on the earthen shoulder and in the central median.
Placement of foundation and supporting structures shall be sufficiently away from the paved surface. Overhead gantry and cantilever supports within the clear zone shall be shielded by a safety barrier system.
Overhead guide signs may be, where practicable, mounted on overpass structures above the expressway to minimize the number of potentially hazardous roadside structures.
For Cantilever mounted signs, the centre of the sign is typically located over the carriageway edge line; however the left edge of the sign shall be positioned no further left than the left edge of paved shoulder. On exit ramps, guide signs shall be located over the relevant lanes.
Where a number of signs are erected on gantry, the outer edges of signs shall not extend beyond the outer edges of paved shoulders. The desirable minimum distance over which signs should be seen is the legibility distance of the principal legend size, plus an additional one third of this distance to allow sufficient time for the driver to see the sign prior to reading its text. Overhead signs shall be placed on a structurally sound gantry or cantilever structure made of Gl pipes.
Overhead Gantry shall be mounted at 5. Cantilever Gantry shall be mounted at a height of 5. Typical overhead mounted and cantilever mounted structures for signs are given in Fig. Interchange numbering shall be used in signing each expressway exit. Interchange exit numbers shall be displayed with each Advance Guide sign, Exit direction sign and Gore sign.
The exit number shall be displayed on a separate plaque at the top of the Advance Guide or Exit direction sign. Interchange exit numbering can be either i Reference location sign numbering km-base or ii Consecutive numbering and shall be decided in consultation with the Authority and the Independent Engineer. Typical Exit km numbering sign is shown in Fig The Advance Guide sign gives notice well in advance of the exit point of the principal destinations served by the next interchange and the distance to that interchange.
Advance Guide sign should be placed at m, 1 km and at 2 km in advance of the exit. Fractions of kilometers or decimals of kilometers should not be used. Delete Section 33 11 00 entitled Water Distribution and Transmission. Delete Section 33 31 00 entitled Sanitary Sewerage Systems. Delete Section 33 41 00 entitled Drainage Systems. Add Section 33 08 00 entitled Commissioning of Water Utilities attached hereto.
Add Section 33 11 00 entitled Water Distribution and Transmission attached hereto. Add Section 33 31 00 entitled Sanitary Sewerage Systems attached hereto. Add Section 33 41 00 entitled Drainage Systems attached hereto. Delete Section 32 12 Add Section 32 01 31 entitled Pavement Smoothness attached hereto.
Add Section 32 12 05 entitled Bituminous Concrete attached hereto. Add Section 32 12 Section 32 12 05 entitled Asphalt Concrete previously changed by Amendment No. Section 32 01 Section 32 12 05 - Bituminous Concrete Section 32 12
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