基于DIC技术的自密实混凝土界面裂缝扩展规律研究OA北大核心CSTPCD

A novel engineering structure is introduced,in which the self-compacting concrete is used as the anti-abrasion layer of the rock-filled concrete dam,and then cast in place with the dam body.Therefore,the performance of the interface between the anti-abrasion layer and the dam body is crucial to the stability of the whole structure.600 mm×600 mm×600 mm self-compacting concrete(SCC)specimens(C40SCC,C25SCC)and layered pouring specimens(C40-C25SCC)were prepared for the splitting tensile tests,and the digital image correlation(DIC)technique was adopted for the analysis of the crack propagation behavior at the SCC interface.The results show that the failure modes of SCC were the splitting and spalling of aggre-gates;the splitting tensile strengths of C40SCC,C25SCC and C40-C25SCC were 1.861,1.416 and 1.362 MPa,respectively.The crack-related parameters were obtained based on DIC technique,among which the maximum crack opening width and propagation time of C40-C25SCC were the largest,measuring 0.125 mm and 10.667 ms,respectively.The fastest crack propagation speed was observed in C25SCC,which was 10.12 m/s.The study demonstrates that the presence and size of aggregates affect the failure mode of the speci-mens,as well as the variation of crack opening width and propagation speed.