合肥红砂岩点荷载强度及其与抗压和抗拉强度的关系  

Point Load Strength of Hefei Red Sandstone and Its Relationshipwith Compressive and Tensile Strength

作　　者：方晴瑶 姚华彦[1] 刘武[1] 巩胜 刘勇志 张明远 FANG Qing-yao;YAO Hua-yan;LIU Wu;GONG Sheng;LIU Yong-zhi;ZHANG Ming-yuan(Civil and Hydraulic Engineering College,Hefei University of Technology,Hefei 230009,China;China Railway Fourth Survey and Design Institute Group Co.,Ltd.,Wuhan 430063,China;Hean High-Speed Railway Co.,Ltd.,Hefei 230601,China)

机构地区：[1]合肥工业大学土木与水利工程学院,合肥230009 [2]中铁第四勘察设计院集团有限公司,武汉430063 [3]合安高铁股份有限公司,合肥230601

出　　处：《科学技术与工程》2024年第30期13101-13109,共9页Science Technology and Engineering

基　　金：安徽省自然科学基金(2208085ME153);安徽高校协同创新项目(GXXT-2022-020)。

摘　　要：点荷载试验是获取岩石强度的快捷方法之一。为了分析合肥地区典型红砂岩点荷载强度与抗压和抗拉强度的关系,对合肥地区的红砂岩,分别开展了干燥和饱水的状态下的点荷载、单轴抗压及巴西劈裂试验。探讨砂岩点荷载计算方法中贯入深度及修正指数m对点荷载强度值的影响,获得了点荷载强度与抗压、抗拉强度的换算关系。试验结果表明:考虑贯入深度与不考虑贯入深度两种计算模式变异系数皆小于0.3,不考虑贯入深度的计算模式数据指标更稳定;修正指数的取值对修正后的点荷载强度值I′s(50)C、I s(50)C影响很小,实际应用中可采用0.45作为修正指数;点荷载两种计算模式的软化系数相近,考虑贯入深度影响的软化系数比不考虑贯入深度的软化系数小;相同岩石的点荷载强度、抗压及抗拉强度软化系数差别不大,有良好的相关性;获得了砂岩点荷载强度与其拉压、抗拉强度转换系数范围,可为合肥地区工程应用提供参考。Point load test is one of the quick methods to obtain rock strength.In order to analyze the relationship between point load strength and compressive and tensile strength of typical red sandstones in Hefei area,point load,uniaxial compressive and Brazillian tests were carried out on red sandstones in dry and saturated state.The influence of penetration depth and modified index m on the point load strength of sandstone was discussed,and the conversion relationship between the point load strength and compressive and tensile strength was obtained.The results show that the coefficient of variation is less than 0.3 for both models with and without penetration depth,and the data index of the model without penetration depth is more stable.The value of the correction index has 0x0E䥺Symbol`@@0x0Flittle influence on the corrected point load strength values I′s(50)C and I s(50)C,and 0.45 can be used as the correction index in practical application.The softening coefficients of the two models are similar,and the softening coefficients considering the penetrationdepth are smaller than those without considering the penetration depth.The softening coefficients of point load strength,compressive strength and tensile strength of the same rocks have little difference and good correlation.The obtained point load strength of sandstone and its conversion coefficient range of tensile,compressive and tensile strength can provide reference for engineering application in Hefei area.

关 键 词：砂岩 点荷载强度 抗压强度 抗拉强度 软化系数 

分 类 号：TU458.3[建筑科学—岩土工程]