Experimental study on mechanical properties of weak interface of rammed earth structure

Abstract

Under the action of an earthquake, the rammed earth structure will produce shear failure due to insufficient shear strength. This damage is more serious at the weak interface of each rammed earth layer. In order to study the shear strength of each weak interface, through large-scale direct shear tests, the effects of different modification ratios and sheet roughness on the shear strength, cohesion, internal friction angle and failure morphology of each weak interface were studied. The results of the study show that the addition of modified materials can significantly increase the shear strength of the rammed earth-rammed earth interface. Under different normal pressures, 15% cement has the best lifting effect, but it has the best resistance to rammed earth and building boards. The shear strength has little effect; The shear strength at the interface between the rammed earth and the plate is also affected by the normal pressure, the surface roughness of the plate and the strength of the rammed earth material; The curing agent is significantly improved by improving the bonding effect between particles. The shear strength at the interface of the rammed layer is not obvious, but the influence on the angle of internal friction is not obvious.