Posted By: technopediasite
Spacing Between Man -holes/Hand-holes
➤ Man-holes/hand-holes shall be provided to facilitate optical fibre cable blowing, jointing and storing loops of fibre cable for future use during maintenance activities. There is no difference in construction of man-hole and hand-holes. They are named so to distinguish the functions they perform. Man-hole is used for jointing of fibre and joint closures will be installed inside the man-hole chamber. The hand-hole shall be used for only storing extra optical fibre cable loops.
➤ In case of inter-city routes, man-holes shall be installed along the route at a spacing not exceeding 4km. In between two man-holes, hand-holes shall be installed. The spacing between two adjacent man-hole/hand-hole and handholes/ man-hole shall not exceed 1km.
➤ For intra-city routes (Including inter-city routes in common with intra-city routes) man-hole/hand-hole spacing shall be indicated in approved for construction drawings.
Design of Man -hole/Hand-holes
➤ Design of man-holes and hand-holes shall be as per approved for construction drawings issued by Company. MH on intra-city section of intercity routes (i.e. NLD overlaid with intra-city path) shall be rectangular of square as per intra-city specifications. Depth of MH shall be 1200mm for cities where primary installation method is specified as HDD and 1650mm where primary mode of installation is specified as open trenching.
➤ Man-hole / hand-hole covers for intra-city routes shall be suitable for grade MD-10 or HD-20 or EHD 35, depending on their location.MH body and cover ring shall be suitable for corresponding loading.Type and grade of manhole to be used shall be indicated in approved for construction drawings. Generally covers of MH on footpaths / non carriage way areas shall be suitable for grade MD-10, one on road carriage way shall be suitable for grade HD-20 and those installed on carriage way of roads having high frequency heavy traffic shall be suitable for grade EHD-35.
➤ Man-holes and hand-holes shall be of adequate size to accommodate number of joint closures and associated loops for each OFC specified in approved for construction drawings. Minimum MH size for various paths shall be as follows:
Core paths (AG1/AG2/NLD) : 800mm x 900mm
CSS Paths : 600mm x 900mm
All MH at locations where more than one route merges shall (irrespective of ring type) be of size 900mm x 900mm.
➤ Use of Cast-in-situ concrete MH/ hollow block MH made at site shall be minimized unless pre-cast/pre-fabricated MH cannot be used due to presence of utilities or other space constraints.
Installation of Man -holes/Hand-holes
➤ In general and specifically for inter-city routes, the man-holes/hand-holes shall be installed such that the lid would be buried at least 500mm below the natural ground surface. It's depend upon the company specifications.
➤ In intra-city where adequate depth of burial is not available, the man-hole lid shall be installed flush with ground surface. In no case the lid shall protrude above surrounding surface.
➤ Manholes at the crossings shall not encroach into the easement / RoW of the existing utility/facility.
➤ The man-holes/hand-holes shall be installed over well compacted ground and over a layer of concrete base.
➤ The entry of the duct into man-hole/hand-hole shall be smooth and at its floor level. Sharp bends to force the entry shall be avoided. Always, sequence of ducts on both entry and exit side shall be same.
➤ All openings after installation of ducts shall be closed with cement grout or equivalent method to prevent entry of rodents, snakes, insects etc.
Spacing Between Man -holes/Hand-holes
➤ Man-holes/hand-holes shall be provided to facilitate optical fibre cable blowing, jointing and storing loops of fibre cable for future use during maintenance activities. There is no difference in construction of man-hole and hand-holes. They are named so to distinguish the functions they perform. Man-hole is used for jointing of fibre and joint closures will be installed inside the man-hole chamber. The hand-hole shall be used for only storing extra optical fibre cable loops.
➤ In case of inter-city routes, man-holes shall be installed along the route at a spacing not exceeding 4km. In between two man-holes, hand-holes shall be installed. The spacing between two adjacent man-hole/hand-hole and handholes/ man-hole shall not exceed 1km.
➤ For intra-city routes (Including inter-city routes in common with intra-city routes) man-hole/hand-hole spacing shall be indicated in approved for construction drawings.
Design of Man -hole/Hand-holes
➤ Design of man-holes and hand-holes shall be as per approved for construction drawings issued by Company. MH on intra-city section of intercity routes (i.e. NLD overlaid with intra-city path) shall be rectangular of square as per intra-city specifications. Depth of MH shall be 1200mm for cities where primary installation method is specified as HDD and 1650mm where primary mode of installation is specified as open trenching.
➤ Man-hole / hand-hole covers for intra-city routes shall be suitable for grade MD-10 or HD-20 or EHD 35, depending on their location.MH body and cover ring shall be suitable for corresponding loading.Type and grade of manhole to be used shall be indicated in approved for construction drawings. Generally covers of MH on footpaths / non carriage way areas shall be suitable for grade MD-10, one on road carriage way shall be suitable for grade HD-20 and those installed on carriage way of roads having high frequency heavy traffic shall be suitable for grade EHD-35.
➤ Man-holes and hand-holes shall be of adequate size to accommodate number of joint closures and associated loops for each OFC specified in approved for construction drawings. Minimum MH size for various paths shall be as follows:
Core paths (AG1/AG2/NLD) : 800mm x 900mm
CSS Paths : 600mm x 900mm
All MH at locations where more than one route merges shall (irrespective of ring type) be of size 900mm x 900mm.
➤ Use of Cast-in-situ concrete MH/ hollow block MH made at site shall be minimized unless pre-cast/pre-fabricated MH cannot be used due to presence of utilities or other space constraints.
Installation of Man -holes/Hand-holes
➤ In general and specifically for inter-city routes, the man-holes/hand-holes shall be installed such that the lid would be buried at least 500mm below the natural ground surface. It's depend upon the company specifications.
➤ In intra-city where adequate depth of burial is not available, the man-hole lid shall be installed flush with ground surface. In no case the lid shall protrude above surrounding surface.
➤ Manholes at the crossings shall not encroach into the easement / RoW of the existing utility/facility.
➤ The man-holes/hand-holes shall be installed over well compacted ground and over a layer of concrete base.
➤ The entry of the duct into man-hole/hand-hole shall be smooth and at its floor level. Sharp bends to force the entry shall be avoided. Always, sequence of ducts on both entry and exit side shall be same.
➤ All openings after installation of ducts shall be closed with cement grout or equivalent method to prevent entry of rodents, snakes, insects etc.
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