Experimental analysis and numerical calculation on equivalent strength of induced joints of different ages and weakening degrees

Abstract

As with any concrete dam, temperature stress is a major issue and when it exceeds its maximum limits cracks may occur, the roller compacted concrete (RCC) arch dam is no exception. To overcome this issue, the specific setting of induced joints in the dam can induce cracks at these positions reducing the effect of temperature cracks. However, the study of the induced joints usually ignores the influence of concrete age on the induced joints, thus the obtained equivalent strength of the induced joints deviate from the actual situation. In this paper, the axial tensile test of the both-way interval induced joint test piece of RCC is carried out, in which quantitative analysis is performed on the variation rules of its equivalent strength under different ages and degrees of weakening. The finite element calculation software was also used to perform numerical simulation of the axial tensile test piece, and conduct comparison and analysis between the simulation and test results, thus verifying the correctness and reliability of the equivalent strength model of the both-way interval non-penetrating induced joint established by the test. According to the stress distribution cloud map of the simulated induced joint, the development process of the induced crack under the load was analyzed to propose a more reasonable type of induced joint layout, thus further optimizing the fracture test of the RCC induced joints, and providing a basis for the design of induced joints in actual engineering practice.