改性高水材料尺寸与形状效应研究

发布时间：2018-06-25 07:02

本文选题：高水材料 + 力学性质　；参考：《工程科学与技术》2017年S2期

【摘要】：改性高水材料是在原高水材料的基础上通过掺杂或改性,以达到提高其物理力学性质和降低经济成本等目的的新型高水材料,近年来在地下采空区充填支护等领域得到了广泛应用。同岩石和混凝土等材料一样,其形状和尺寸对力学性质影响显著,因此对改性高水材料形状和尺寸效应的研究具有重要意义。为研究不同形状和尺寸改性高水材料的力学性质,借助ETM力学试验系统,通过对不同尺寸和形状下的改性高水材料的破坏过程、抗压强度和变形特性等性质的测试,系统研究改性高水材料的尺寸和形状效应。结果表明:改性高水材料是一种弹塑性材料,其变形破坏过程可以分为弹性阶段、屈服阶段、塑形阶段和破坏阶段4个过程;改性高水材料的尺寸仅影响其应力-应变曲线峰值强度,对曲线的形状几乎没有影响,而形状对应力-应变曲线的峰值强度和形状均有较大影响;相对于圆柱体试件,立方体试件的全应力-应变曲线屈服后下降得更加缓慢;随着材料尺寸的增加,圆柱体和立方体试件的抗压强度、弹性模量和变形模量均在一定范围内逐渐减小,且当试件尺寸较小时(小于100mm),尺寸增加25%,弹性模量降低约50%,变形模量约降低10%,尺寸较大时(大于100 mm),变化率急剧减小;在相同条件下,圆柱体试件的抗压强度、弹性模量大于立方体试件,变形模量小于立方体试件。
[Abstract]:The modified high water material is a new kind of high water material, which can improve its physical and mechanical properties and reduce the economic cost by doping or modifying the original high water material. In recent years, it has been widely used in the field of underground goaf filling and supporting. As the materials such as rock and concrete, the shape and size of the modified materials have a significant effect on the mechanical properties, so it is of great significance to study the shape and size effects of the modified high-water materials. In order to study the mechanical properties of modified high water materials with different shapes and sizes, the failure process, compressive strength and deformation characteristics of the modified high water materials with different sizes and shapes were tested by means of ETM mechanical test system. The size and shape effects of modified high-water materials were studied systematically. The results show that the modified high water material is an elastoplastic material, and its deformation and failure process can be divided into four stages: elastic stage, yield stage, plastic stage and failure stage. The size of modified high water material only affects the peak strength of stress-strain curve, and has little effect on the shape of the curve, but the shape has a great effect on the peak strength and shape of stress-strain curve. The compressive strength, elastic modulus and deformation modulus of the cylinder and cube specimen decrease gradually with the increase of material size, and the total stress-strain curve of the cube specimen decreases more slowly after yielding, and the compressive strength, elastic modulus and deformation modulus of the cube specimen decrease gradually with the increase of the material size. And when the size of the specimen is smaller (less than 100mm), the size increases by 25%, the elastic modulus decreases about 50%, the deformation modulus decreases about 10%, and when the size is larger (> 100 mm), the compressive strength of the cylinder specimen decreases sharply under the same conditions. The elastic modulus is larger than the cube specimen, and the deformation modulus is smaller than the cube specimen.
【作者单位】：四川大学水力学与山区河流开发保护国家重点实验室;四川大学水利水电学院;四川电力设计咨询有限公司;
【基金】：国家重点基础研究发展计划资助项目(2010CB226802) 国家自然科学基金煤炭联合基金重点资助项目(51134018)
【分类号】：TU526

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