While constructing long embankment (appx 4 km) in multiple layers of 300mm depth, what shall be spacing of core cutter samples to ensure adequate dry density measurement.
Height of Instrument : It is the method which deals with the obtaining of RL of the line of collimation by adding BS reading of a known RL point. Thus, RL of the line of collimation is called the Height of Instrument. It is always measured from the benchmark. Hence the benchmark is the point on theRead more
- Height of Instrument :
It is the method which deals with the obtaining of RL of the line of collimation by adding BS reading of a known RL point. Thus, RL of the line of collimation is called the Height of Instrument. It is always measured from the benchmark. Hence the benchmark is the point on the sea derived from mean sea level.
– method to calculate RL;
height of collimation (H of C) = reduced level(R.L.) + backsight (B.S.)
reduced level (R.L.) = height of collimation (H of C) – foresight (F.S.)
reduced level (R.L.) = height of collimation (H of C) – intermediate sight (I.S.)
- Rise & fall method :
It is the method which gives the difference of elevation between consecutive points by comparing each point after the first that immediately preceding it. Rise and fall are indicated by the difference in staff reading. After that RL is found by adding the rise to or subtracting the fall from the reduced level of the preceding point.
– method to calculate RL;
fall (F) = foresight (F.S.) – backsight (B.S.)
fall (F) = intermediate sight (I.S.) – backsight (B.S.)
rise (R) = backsight (B.S.) – foresight (F.S.)
reduced level (R.L.) = precede reduced level + rise (R)
reduced level (R.L.) = precede reduce level – fall (F)
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AdityaBhandakkar
Hi, There are not any specific criteria for the spacing of sample taken, and the decision is purely based upon site civil engineers and various criteria of soils and on observations. if you found soil which is less compacted or even is created then take samples for observation and check the bulk denRead more
Hi, There are not any specific criteria for the spacing of sample taken, and the decision is purely based upon site civil engineers and various criteria of soils and on observations. if you found soil which is less compacted or even is created then take samples for observation and check the bulk density of soil and moisture content. Please refer to the following article for details about core cutter method and its applications: Link: https://theconstructor.org/geotechnical/dry-density-of-soil-by-core-cutter-method/2680/
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