PACKAGE : I Bid Document VOLUME : II - Public Health Engineering

5.9 Over excavation of trench bottom.
All excavation carried below the grades shown on drawings or bottom of the
bedding shall be refilled with sand/concrete at the Contractor's expense.
5.10 Excavated material.
The material from the excavation shall be deposited on either side of the trench
leaving clear berm on one side at least 40cm wide or at such further distance from
the edges of the trench as may be necessary to prevent the weight of materials from
causing the side of the trench to slip or fall, or at such a distance and such a manner
as to avoid any wall or structure or causing inconvenience to the public or other
persons or otherwise as the Engineer may direct, till it is carted away.
The excavated soil should be so placed and handled as not to inconvenience the
usual traffic, till it is carted away. The Contractor should also provide necessary
bridging over the excavated trenches for the house-holders and pedestrians to cross
over and vehicular crossings if and where required at no extra cost; if the Engineer
decides that there is no hindrance to traffic due to not carting away the excavated
earth, he will give instructions to that effect. The Contractor shall be responsible for
making all arrangements for the disposal of surplus excavated material upto a
distance of 10kms.
5.11 Pipe bedding.
Sand Bedding: Where specified, the river sand bedding the required thickness and
level shall be provided below pipe prior to laying the pipe in trenches. It shall be
compacted with a light hand hammer. Any reduction in compaction shall be made
up by adding sand during ramming. For the purpose of bedding under this item,
only screened fine sand of grain size not larger than 2mm shall be used. The sand
shall be clean, uncoated and free from clay lumps, injurious amount of dust, soft
particles, organic matter, loam or other deleterious substances.
If the sand supplied is unclean, it shall be washed. In no case shall sand containing
more than 3.5% by dry volume or 5% by wet volume of clay, loam or silt be
accepted. Tests specified for determining silt in sand and organic impurities
described in IS: 383 shall apply. Sieved and washed sand shall be stored on the
works in such a manner as to prevent intrusion of any foreign matter, including
coarser particle of sand or any clay or metal or chips. Tests as indicated above shall
be performed if called for by the Engineer at the expense of the Contractor.
GTS : General Technical Specification. Page 36