Quality Assurance Handbook for Rural Roads Volume-I - pmgsy

3. Section-1300
A-3 Toe Protection
The toe wall shall be in dry RR matting conforming to the Clause 1302.5 of MORD Specifications
for Rural Roads or as per drawings. Toe protection shall be done by constructing a toe wall,
retaining/breast wall or close bamboo walling at the junction of embankment slope and general
ground level, to protect the embankment from damages.
1. Use dry rubble or brick masonry for toe walls.
2. While using bamboo walling, examine the ballies of 65mm to 75mm dia from a distance of 1.2m
from wider end. Paint the entire length in coal tar.
3. Choose lengths between 1.2m and 3m and drive the ballies into the ground at close intervals of
150 mm c/c. Use atleast three half split runner/stays at equal spacing for horizontal stiffness and
fix them with nails.
4. Line the exposed surface of bamboo walling with sheets made of cut drums and fix with nails.
A-4 Rubble Stone/Brick flooring
1. Where specified provide rigid flooring under culverts and extend for a minimum distance of 1.5
m on upstream side and 3m on downstream side or as shown in drawings.
2. Excavate trench for laying foundation of bed protection and lay 150 mm thick cement concrete of
M10 grade, so as to commence paving work.
3. Where rubble stone is specified as flooring, carryout the work with flat stones 150 mm thick,
which are bedded on a 25 mm thick layer of 1:5 cement mortar. Fill the joints with 1:3 cement
mortar.
4. Where bricks are to be used, carryout the work on 150 mm thick brick on edge, with each layer of
brick bedded on 25 mm thick 1:5 cement mortar. Fill in the joints with 1:3 cement mortar.
5. Keep the top of flooring 300 mm below the lowest bed level and extend the flooring. Extend the
line connecting the end of splayed wing walls on either side of the culvert/bridge.
6. Adopt dry rubble stone/brick flooring at CD works where the velocity of flow is less than 1.5 m/
sec by keeping the top of flooring 300 mm below the low bed level.
7. Lay the rubble stones closely, breaking joints and fill all joints with spalls of proper size and
wedged in with rammers to ensure tight packing.
8. When dry brick is to be used, follow the procedure as above on a prepared base and lay in one or
more layers. Ensure proper bond.
A-5 Curtain wall
Enclose flooring by curtain walls in cement concrete (M 10) or stone/brick masonry in cement
mortar 1:4 and take to a depth of atleast 1.5 m on u/s side and 2 m on d/s side below the floor
level.
A-6 Chute drain, Roadside drain, Hillside drain, Catch water drain
1. Provide rectangular or trapezoidal chute drains of specified dimensions in sections of road
embankment, of height more than 8 m at minimum 10 m intervals. Provide them in embankment
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