岩石轴向直接拉伸试验装置的研制及应用  

DEVELOPMENT OF TEST DEVICE FOR DIRECT AXIAL TENSION ON ROCK AND ITS APPLICATION

作　　者：张绪涛[1,2] 张强勇[1] 袁圣渤[1] 王超[1] 高强[1] 

机构地区：[1]山东大学岩土与结构工程研究中心,山东济南250061 [2]聊城大学建筑工程学院,山东聊城252059

出　　处：《岩石力学与工程学报》2014年第12期2517-2523,共7页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(41172268,51279093);国家科技重大专项(2011ZX05014)

摘　　要：针对目前已有岩石直接拉伸试验装置的不足,研制轴向对中装置包括黏接对中装置和拉伸对中装置,两套对中装置可分别消除岩石试件黏接过程中的偏心和拉伸过程中的偏心,保证试件处于轴心受拉的状态。使用轴向对中装置和万能试验机,采用标准岩石试件进行直接拉伸试验,测试砂岩、灰岩和花岗岩的抗拉强度、极限拉应变和拉伸弹性模量,并给出拉应力–应变曲线。直接拉伸试验结果表明:岩石试件的拉断破坏面大都出现在试件中部;绝大部分岩石试件为脆性拉断破坏;岩石内部的裂隙对其抗拉性能影响很大,为了能精确测试岩石的抗拉强度指标,试验前应对试件进行严格的筛选。To overcome the deficiency of existing direct tension test device,axial positioning devices were developed,including an axial positioning device for bonding and an axial positioning device for tension. The two sets of axial positioning devices eliminated the bonding eccentricity and the tensile eccentricity respectively, ensuring that rock specimen be pulled in uniaxial tension state. The direct tension tests of rocks were then carried out using the axial positioning devices and the universal testing machine. The tensile strength,the ultimate tensile strain and the tensile elastic modulus of sandstone,limestone and granite were measured. In the direct tensile test, the standard rock specimen was used. The tensile stress-strain curves of these rocks were obtained. The failure surfaces of rock specimen were found to appear at the middle of specimen mostly. The most of the rock specimens displayed the mode of brittle failure. The fractures of rock influenced greatly the tensile properties of rock. In order to measure the tensile strength of rock accurately,the rock specimen should be selected strictly before testing.

关 键 词：岩石力学 轴向对中装置 直接拉伸试验 抗拉强度 拉应力-应变曲线 

分 类 号：TU45[建筑科学—岩土工程]