三峡库区典型土石混合体与混凝土接触面大型剪切试验研究

利用大型直剪仪和单剪切仪,对三峡库区典型土石混合体—混凝土接触面力学特性开展了不同试验方法和不同法向应力的剪切试验,对比分析了直剪和单剪试验条件下土石混合体—混凝土接触面的抗剪强度和变形特性,试验表明,界面应力应变特性与试验方法、法向应力水平有关。低法向应力情况下,直剪和单剪试验界面应力应变曲线均表现为硬化型,高法向应力情况下,直剪为应变软化型,单剪为应变硬化型,通过单剪试验结果分析得到了剪切破坏带及其厚度,研究成果能为土石混合体地质体与混凝土结构共同作用分析提供参考。

Large shearing test on interface between typical earth-rock aggregate and concrete in Three Gorges Reservoir Area

Based on large direct shear apparatus and simple shear apparatus， the shearing test on the mechanical behavior of the interface between the typical earth-rock aggregate and concrete in Three Gorges Reservoir Area is made with various testing methods and various normal stresses， and then the shearing strength and deformation characteristics of the interface between the earth-rock aggregate and concrete under the conditions of both the direct shearing test and the simple shearing test are comparatively analyzed. The test shows that the stress-strain characteristics of the interface are related to the testing method and the level of the normal stress. Under the condition of lower normal stress， the stress-strain curve of the interface under direct shearing test and simple shearing test shows a hardened type， while it exhibits a strain softening type under the direct shearing test and strain hardened type under the simple shearing test， thus the shear failure zone and its thickness are obtained through the analysis made on the result of the simple test. The study result can provide a reference for the analysis on the joint effect of both the earth-rock aggregate and concrete.