水灰比对薄喷衬层材料抗拉性能影响的宏微观试验研究  

Macro and Micro Experimental Study of the Effect of Water-Cement Ratio on theTensile Properties of Thin Spray Lining Materials

作　　者：陈庆发 杨文雄 吴家有 牛文静 CHEN Qingfa;YANG Wenxiong;WU Jiayou;NIU Wenjing(Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Guangxi University,Nanning 530004,China;School of Resources,Environment and Materials,Guangxi University,Nanning 530004,China;Guangxi Key Laboratory of Disaster Prevention and Engineering Safety,Nanning 530004,China)

机构地区：[1]广西大学工程防灾与结构安全教育部重点实验室,南宁530004 [2]广西大学资源环境与材料学院,南宁530004 [3]广西防灾减灾与工程安全重点实验室,南宁530004

出　　处：《材料导报》2024年第8期277-283,共7页Materials Reports

基　　金：国家自然科学基金(51964003);广西大学学科交叉科研项目(2022JCB012)。

摘　　要：薄喷衬层材料TSL865作为一种新型高分子喷涂支护材料,可快速有效地抑制地下工程围岩变形、破坏。抗拉性能是TSL865材料的优势特征,但其受水灰比的影响规律与作用机制目前尚不清晰。为此,本研究开展两方面的工作:(1)通过开展宏观拉伸试验,分析水灰比对TSL865试样应力-应变曲线特征、抗拉强度和抗拉韧性等力学性质的影响规律;(2)通过开展微观孔隙结构试验,分析水灰比对TSL865试样微观孔径分布、比表面积等几何性质的影响规律;计算不同水灰比下TSL865试样的孔径分形维数,从试样微观孔径结构分布特征角度,解译水灰比对TSL865试样抗拉性能的影响机制,并获取最佳水灰比。研究结果表明:TSL865试样的应力-应变曲线可以分为弹-塑-延-脆四个阶段,且柔性特征显著;TSL865试样抗拉性能较好的原因是其2~10 nm的无害孔占比较大;水灰比与试样的抗拉强度、孔径分形维数呈负相关关系,通过调节水灰比来改变TSL试样的微观孔隙结构,从而影响TSL试样的抗拉性能,其最优的水灰比为1∶2。研究成果有助于全面了解TSL865材料的抗拉性能与宏细观破断机制。Thin spray-on liner material TSL865, as a new type of polymer spray support material, can quickly and effectively control the deformation and damage of underground engineering surrounding rock. Tensile performance is the advantageous feature of TSL865 material, but its law and mechanism of action influenced by water-cement ratio is still unclear. To this end, this study carried out two areas of work: (1) the influence law of water-cement ratio on mechanical properties such as tensile stress-strain curve characteristics, tensile strength and tensile toughness of TSL865 specimens was analyzed by conducting macro tensile tests;(2)the influence law of water-cement ratio on the geometric properties such as microscopic aperture distribution and specific surface area of TSL865 specimens was analyzed by conducting microscopic pore structure tests;the fractal dimension of aperture of TSL865 specimens with different water-cement ratios were calculated to decipher the influence mechanism of water-cement ratio on the tensile properties of TSL865 specimens from the perspective of microscopic aperture structure distribution characteristics of specimens and their optimal water-cement ratios were obtained. The results show that the tensile stress-strain curve of TSL865 specimen can be divided into four stages: elastic-plastic-delayed-brittle, and the flexibility characteristics are significant. The reason for the better tensile properties of TSL865 specimens is the larger proportion of harmless pores of 2—10 nm. The water-cement ratio is negatively correlated with the tensile strength and fractal dimension of the aperture of the specimen, and the water-cement ratio changes the microscopic pore structure of the TSL specimen, thus affecting its tensile properties, the optimal water to ash ratio is 1∶2. This work contributes to a comprehensive knowledge of the tensile properties and macroscopic breakage mechanism of TSL865 material.

关 键 词：薄喷衬层材料 TSL 水灰比 抗拉性能 孔隙结构 地下工程 

分 类 号：TU52[建筑科学—建筑技术科学]