INVESTIGATION ON THE CHANGE OF SUBGRADE CONDITION AFTER PAVING AND A PROPOSITION WITH IMPROVING THE PRESENT CBR METHOD

Abstract

The essential point in rational design of pavement thickness is to forecast the bearing value of subgrade which reached equilibrium state after paving.
This investigation dealt with the change that occurred in subgrade condition before the subgrade reached on equilibrium state, but the subgrade condition was treated with each element that had a certain inflence to subgrade bearing value, i. e. these elements are soil suction, process on variation of water content after compaction, dry density, compaction method, thixotropic effect.
Also, this paper shows a proposition with improving the present CBR method, the new CBR method introduced a specimen preparing procedure which gives on equiliblium subgrade condition that estimated from the results of above investigation.