Experimental study on direct shear test of rock mass structure for a dam foundation

Value c and Ф are main parameters for measuring the shear-strength of rock mass structure and are generally obtained through direct shear test of rock mass structure.The direct shear test method of rock mass structure includes multi-point method and single point method,but multi-point method is generally adopted in engineering design while the importance of single point method is neglected.In order to compare the two test methods,in the combination of concrete test program and using portable shear apparatus,the test on shear-strength parameter of rock mass structure for dam foundation of a hydropower station was conducted with the two methods.The test result shows that each method has its merits and only their combined use can objectively reflect the shear-strength of rock mass structure,and improve the correctness and reliability of engineering design.