EXCAVATION FOR ROADWAY
THIS WORK SHALL CONSIST OF EXCAVATION, REMOVAL & DISPOSAL OF MATERIALS NECESSARY FOR THE CONSTRUCTION OF ROADWAY, SIDE DRAINS& WATERWAYS IN ACCORDANCE WITH THE REQUIREMENTS OF THESE SPECIFICATIONS & CROSS-SECTION SHOWN IN THE DRAWING OR AS INDICATED BY THE ENGINEER-IN-CHARGE.
CLASSIFICATION OF EXCAVATED MATERIAL
1. SOIL
THIS SHALL COMPRISE OF SAND, SILT, LOAM, CLAY, MUD, BLACK COTTON SOIL, SOFT SHALE OR LOOSE MOORUM, AND A MIXTURE OF THESE MATERIALS.
EQUIPMENT REQUIRED:-
MANUAL LABOUR(PICK, SPADE OR SHOVEL & RAKE)
BY MECHANICAL MEAN
2. ORDINARYROCK (BLASTING NOT REQUIRED)
ROCKS SUCH AS LATERITES, SHALES &CONGLOMERATES
LIMESTONE & SANDSTONE WATERBOUND & BITUMEN BOUND MACADAM, CEMENT CONCRETE PAVEMENT, COBBLE STONE & COMPACTED MAROOM AND BOULDERS WHICH DO NOT REQUIRE BLASTING
3. HARD ROCK (BLASTING REQUIRED)
ANY ROCK AND (CC OR RCC) BELOW GROUND LEVEL OF WHICH THE USE OF MECHANICAL PLANT OR BLASTING IS REQUIRED
BOULDERS REQUIRING BLASTING
4. HARD ROCK (USING CONTROLLED BLASTING )
CONTROLLED BLASTING IS CARRIED OUT IN LOCATIONS WHERE BUILD-UP AREAS & HUTS ARE SITUATED AT WITHIN 200 M OF THE BLAST SITE.
5. HARD ROCK (BLASTING PROHIBITED)
BLASTING IS PROHIBITED FOR ANY REASON LIKE PEOPLE LIVING WITHIN 20M OF BLAST SITES & EXCAVATION IS CARRIED OUT BY CHISELLING, WEDGING OR ANY OTHER AGREED METHOD.
6. MARSHY SOIL
THIS INCLUDES SOFT CLAYS & PEATS.
EXCAVATION IS DONE BELOW OGL OF MARSHES & SWAMPAND SOIL EXCAVATED FROM OTHER ARE AS REQUIRING CONTINOUS PUMPING OR BAILING OUT OF WATER
EMBANKMENTS SUBGRADE CONSTRUCTION
EMBANKMENT FOR CONSTRUCTION
THIS APPLY TO THE CONSTRUCTION OF EMBANKMENT INCLUDING SUB-GRADES, EARTHEN SHOULDERS & MISCELLANEOUS BACKFILL WITH APPROVED MATERIALS OBTAINED FROM APPROVED SOURCE.
PHYSICAL REQUIREMENTS
MATERIALS TO BE USED:- SOIL, MOORUM, GRAVEL, RECLAIMED MATERIALS FROM PAVEMENT, FLY ASH, POND ASH, A MIXTURE OF THESE, OR ANY OTHER MATERIAL AS APPROVED BY THE ENGINEER
MATERIALS NOT TO BE USED:-
1. MATERIALS FROM SWAMPS, MARSHES & BOGS
2. SOIL THAT CLASSIFIES AS OL, OI, OH & Pt
3. COMBUSTIBLE MATERIALS
4. CLAY:- LIQUIDLIMIT>50
PLASTICITYINDEX>25
5. MATERIALS WITH SALTS RESULTING IN LEACHING IN THE EMBANKMENT.
6. EXPANSIVE CLAY HAVING FREE SWELLING INDEX>50% NOTE:- SUBGRADE & TOP 500MM PORTION OF EMBANKMENT JUST BELOW THE SUBGRADE SHALL BE NON-EXPANSIVE IN NATURE
SIZE OF COARSE MATERIALS IN THE MIXTURE OF EARTH
1. FOR EMBANKMENT:- NOT EXCEEDS75MM
2. FOR SUBGRADE:- NOT EXCEEDS 50MM NOTE:-
3. MATERIALS COARSER THAN THIS CAN BE USE BY THE PERMISSION OF THE ENGINEER-IN-CHARGE & IT SATISFIES THE SAME AND WILL NOT PRESENT ANY DIFFICULTY AS REGARDS THE PLACEMENT OF FILL MATERIAL & IT COMPACTION.
4. MAXIMUM PARTICLE SIZE < 2/3 OF THE COMPACTED LAYER
THICKNESS
DRY DENSITY REQUIREMENT OF EMBANKMENT & SUBGRADE MATERIALS:-
NOTE:- THE MATERIALS SHALL SATISFY THE DESIGN CBR AT THE SPECIFIED DRY DENSITY & MOISTURE CONTENT
COMPACTION REQUIREMENT OF EMBANKMENT & SUBGRADE MATERIALS:-
NOTE:-THE CONTRACTOR SHALL SUBMIT THE TEST REPORT AT LEAST 7 DAYS BEFORE THE COMMENCEMENT OF COMPACTION.
1. VALUE OF MAX. DRY DENSITY & OMC
2. GRAPH OF DRYDENSITYPLOTTEDAGAINSTMOISTURECONTENT
SPREADING MATERIALS IN LAYERS:-
THE EMBANKMENT AND SUBGRADE MATERIALS SHALL BE SPREAD IN LAYERS OF UNIFORM THICKNESS IN THE ENTIRE WIDTH WITH A MOTOR GRADER.
COMPACTION :-
THICKNESS OF LAYER NOT MORE THAN 250MM:- VIBRATORY
ROLLER/VIBRATORY SOIL COMPACTOR
THICKNESS OF LAYER NOT MORE THAN 200MM:- 80-100 KN STATIC ROLLER
MOISTURE CONTENT OF SOIL :-
TEST SHALL BE PERFORMED AS PER IS-2720(II):- WATER CONTENT OF SOIL SHALL BE DETERMINED
MEASUREMENTS FOR PAYMENT OF EMBANKMENT & SUBGRADE:-
IT SHALL BE MEASURED SEPARATELY BY TAKING CROSS-SECTION AT SUITABLE INTERVALS AFTER COMPLETION OF CLEANING AND GRUBBING & EMBANKMENT/SUBGRADE.
THE VOLUME OF EARTHWORK SHALL BE COMPUTED IN CUM. BY METHOD OF AVERAGE END AREAS.
MEASUREMENT OF FILL MATERIAL FROM BORROW PITS= NET QUANTITY OF COMPACTED FILLS– NET QUANTITY OF SUITABLE MATERIALS BROUGHT FROM ROADWAYS EXCAVATION