【摘要】 研究岩石区间非定值强度问题以期适应实验室试验有限性、随机性的特点,以此反映岩石强度参数取值的区间性特征及可能性分布。首先,提出了岩石的抗压区间强度、抗拉区间强度的概念;其次,基于区间分析、未确知数学理论,结合实验室实际,给出了区间强度的求解方法,并提出了区间内不同强度代表值的可信度确定方法,有利于工程计算时强度参数的选取。最后,通过小样本和大样本的分析比较,对本文方法的合理性进行了验证。小样本研究表明,取可信度为95%时,岩石抗压、抗拉强度代表值小于常规均值计算得到的值,且常规均值计算求取的岩石抗压、抗拉强度代表值可信度在65%左右,可见通过常规均值计算的结果是偏危险的;将某矿山砂岩的320个试样(大样本)随机分成64组,每组5个试样(小样本),研究发现,320个岩样强度呈正态分布,把平均值238.17 MPa作为该区域砂岩的名义值,64个传统均值有32个的取值的大于名义值,证明小样本下(5个样本),用传统均值代表岩石强度其保证率为50%;64个区间强度有55个包含名义值,准确率为86%,且另外6个区间强度上限值均小于名义值,可见用区间强度代表岩石强度的保证率为95%。区间强度较传统均值更充分地表达了岩石强度的信息,完善了岩石强度参数确定方法,为实际工程设计施工、强度校核及可靠性研究中岩石强度参数的取值提供一条新途径。更多还原

【Abstract】 The interval parameters of rock tensile and compression strength to meet the strength of the limited laboratory tests and the characteristics of randomness and to reflect the range of features and the possibility of distribution are studied.Firstly,the concepts of the interval compression strength and the tensile strength are proposed.Secondly,based on the interval analysis,the blind data theory and laboratory practice,the solution method for the interval strength is proposed.Representative values of rock tensile and compression strength tests and their corresponding faith degrees are obtained using the theory of unascertained mathematics in favor of the project selection.Finally,the availability of the proposed methods is demonstrated by analying small and big samples.The small-sample results show that representative values of the rock strength and tensile strength by the proposed methods are smaller than those of the recommended methods by the conventional average values when the faith degree is 95%,and the faith degree of the conventional average values of rock strength is about 65%.It can be seen the representative conventional average values are dangerous.320 rock specimens(big-sample) in a mine are divided into 64 groups,and each group has 5 rock specimens.The results show that 320 rock specimens follow the normal distributions.The average value of 238.17 MPa is regarded as the true value,and half of 64 conventional average values of strength are larger than the true value.It means that the warrant rate is 50%.55 of 64 interval values of strength contain the true value,and the accuracy rate is 86%.The upper values from another 6 interval strengths are larger than the true value,which means that the warrant rate is 95% when the interval values of strength are representative values.It shows that the method is reasonable.The interval parameters of rock tensile and compression strength improve the rock strength parameters.It provides a new method to select rock strength parameters for conducting the reliability analysis,design and safety verification in actual engineering.更多还原