Sub grade reaction 'k' value IS 9214

This procedure is used to know the modulus of sub grade reaction 'k' value of the road sub grade or runways. Its similar to plate load test in this test. K value may be defined as  pressure of 0.7 kgf/cm2 divided by corresponding settlement. That is when a standard plate of 75 cm dia is subjected to 3100 kgf load

k= 0.7/d (kgf/cm2/cm) where d is settlement in cm

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