In high arch dam abutment stability geomechanical model test

the relative displacement of weak structural plane is the important reference to determine dam abutment instability and analyze whole dam abutment safety degree. But the current measuring instruments

such as resistance strain gage

surface displacement meter just can measure the strain of dam body and displacement of surface dam abutment; for the relative displacement of weak structural plane which in dam abutment is difficult to obtain. So in light of this problem

based on the resistance strain gage technology

a new type of inbuilt displacement system has been developed and installed on the structural planes to obtain the relative displacement of structure. This system are composed by signal acquisition instrument

Wheatstone bridge and displacement sensor. In model test

strain changing process is got using the inbuilt displacement system; and displacement value is got through the strain-displacement curve. In integral stability geomechanical model test of Jinping high arch dam

installing this system in weak structural plane

the relative displacement is obtained efficiently during the loading process. Comparing with the strain and the abutment surface displacement monitoring results

the feasibility of inbuilt displacement system is proved. The results can provide reliable data to determine the overall stability of the dam and foundation.