软-硬自然节理的改进JRC-JCS剪切强度公式

发布时间：2018-05-14 13:57

本文选题：软-硬节理 + 节理壁面强度JCS　；参考：《岩土力学》2017年10期

【摘要】：借助三维白光扫描技术和3D打印技术,浇筑了若干块含相同自然节理面、上下盘壁面强度不同的吻合软-硬节理混凝土试块,并对其进行了不同常法向应力下的剪切试验。试验表明,试件的剪胀程度随着节理壁面强度系数λ_(σc)值的增大而增大,剪切强度随着λ_(σc)值的增大而减小。同时,研究表明,对于软-硬节理,在剪切过程中,软-硬节理两侧都发生了破坏,节理的等效壁面强度JCS_(等效)受壁面强度系数λ_(σc)的影响,相对于硬节理侧,较软节理侧对等效壁面强度JCS_(等效)的贡献更大,并且这种趋势随壁面强度系数λ_(σc)的增大而增强,这也是JRC-JCS(节理粗糙系数-节理壁面强度)强度公式预测软-硬节理强度时具有一定局限性的原因。根据以上分析,以较软节理侧的壁面强度JCS软为基准,建立了关于壁面强度系数λ_(σc)的修正关系函数f(λ_(σc))来确定软-硬节理的等效壁面强度JCS_(等效),进而提出了考虑软-硬节理不同壁面强度组合类型的修正JRC-JCS剪切强度公式,该新公式是对现有的JRC-JCS强度公式的完善。
[Abstract]:With the help of 3D white light scanning technology and 3D printing technology, several concrete specimens with the same natural joint surface and different strength of upper and lower wall are constructed, and the shear tests are carried out under different normal stresses. The test results show that the shear expansion degree increases with the increase of the strength coefficient 位 (蟽 _ c) of the jointed wall, and the shear strength decreases with the increase of the value of 位 _ (蟽 _ c). At the same time, the study shows that, for soft hard joints, both sides of soft hard joints are destroyed during shear, and the equivalent wall strength of joints is affected by the wall strength coefficient 位 (蟽 c), relative to the hard joint side, the equivalent wall strength of the joint is affected by the wall strength coefficient 位 (蟽 c), and the equivalent wall strength of the joint is affected by the wall strength coefficient 位 (蟽 c). The contribution of the soft joint side to the equivalent wall strength is greater, and this trend increases with the increase of the wall strength coefficient 位 (蟽 c). This is also the reason why JRC-JCS (joint roughness coefficient-joint wall strength) strength formula has some limitations in predicting soft-hard joint strength. Based on the above analysis, the wall strength of the soft joint side is taken as the reference for JCS soft. The modified relation function f (位 (蟽 _ c) of wall strength coefficient 位 _ S (蟽 _ c) is established to determine the equivalent wall strength of soft-hard joints. Furthermore, a modified JRC-JCS shear strength formula considering different wall strength combinations of soft-hard joints is proposed. The new formula is perfect for the existing JRC-JCS strength formula.
【作者单位】：东北大学深部金属矿山安全开采教育部重点实验室;中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室;
【基金】：国家重点研发计划(No.2016YFC0600707,No.2016YFC0801605) 国家自然科学基金资助(No.41372315)~~
【分类号】：TU45

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