SKP has completed various projects of Seismic data acquisition work for Pipelines & Power plants for various Public & private organizations like GSPL, HPCL, GAIL, BPCL, Mecon, Reliance, etc.
Seismic Analysis Survey
Proposed Route are superimposed on Seismotectonic Map and if pipeline is cutting any fault line, the alignment upto distance of 2 Km on either side of fault line shall be treated as seismic area and it is shown on the alignment sheet as well as on ground.
Bore holes are carried out generally up to 5.0m depth below existing ground level. SPT tests are conducted in boreholes at depths 0.50m, 2.0m, 3.50m & 5.0m. Undisturbed samples (UDS) are collected from depths 1.0m, 2.50m & 4.0m (if the strata is suitable to collect the samples). These samples are tested in the laboratory.
Cross Hole Seismic Test:
The cross hole seismic test is conducted on field as per the ASTM D 4428/IS 13372 (Part 2):1992 and the test are carried out generally at 1.5m interval throughout the depth of borehole of 30 M.
The Cross Hole Seismic test consists of generation of horizontally traveling P and S waves at a particular level in one borehole (Source Hole) and recording their arrivals at same level in two nearby boreholes (Receiver Holes).
Equipments & accessories used:
Soil Stratification and Classification Survey
Augur boring is carried out at 500 m interval, using 150 mm dia. Post hole manual augurs and soil samples are collected for visual classification. The depth of boring is generally up to 3 m from the NGL or refusal (rock encountered) whichever is earlier.
Additional boreholes are done at interval of 50 m in dry river beds. In case of flowing rivers, one borehole are done on each bank up to 5 m depth or refusal (rock encountered) whichever is earlier.
To carry out the soil resistivity measurement using 4 pin Wenner’s method, the soil resistivity readings shall normally be taken at an interval of 500 m interval, at a depth of 100 cm, 300 cm and 500 cm.
Sampling & Soil Chemical Analysis
Disturbed samples are collected from boreholes and laboratory testing is done at Soil Testing Laboratory or NABL Accredited Laboratory.
Soil and water samples are collected at a depth of 1 mtr. and 2.5 mtr. at 1 km interval for chemical analysis.