岩土力学2017，Vol.38Issue(11)：3247-3254,8.DOI:10.16285/j.rsm.2017.11.021
酸腐蚀后灰岩动态压缩力学性质的试验研究
Experimental study of dynamic compressive mechanical properties of limestone after acid corrosion
摘要
Abstract
Rock is usually corroded by chemicals in groundwater.Meanwhile,deformation and failure of rock occur frequently due to the dynamic load in underground engineering.Hence,this study aims to investigate dynamic mechanical properties of limestone corroded in an acid environment.Limestone samples were firstly soaked at pH=3 of KHSO4 solution and NaCl solution for different days,respectively.Then,the porosity,pore size distribution and magnetic resonance image of some samples were obtained by using the nuclear magnetic resonance (NMR) test.Finally,uniaxial dynamic compressive tests were conducted at five strain rates by using the split Hopkinson pressure bar (SHPB) system.The experimental results showed that the porosity of limestone increased sharply with increasing the corrosion time.After 28 d corrosion,the porosity increased from 0.26％ in the natural state to 3.20％.Besides,the micro-pores in limestone samples expanded obviously with the corrosion time.It is found that the dynamic compressive strength was significantly reduced (30.3％) and can be divided into two stages according to the descent rate.Moreover,the dynamic elastic modulus and specific energy-absorption decayed exponentially with time.Under natural state and post-corrosion state,limestone samples both exhibited similar responses to the strain rate.Specifically,the failure mode changed from the typical splitting failure to the tensile-shear failure,shear failure,even powders with increasing strain rate.Moreover,the dynamic compressive strength and elastic modulus increased linearly.However,these two mechanical parameters of limestone were both more sensitive to the strain rate in a natural state than post-corrosion.It is proven that the effect of acid corrosion on the dynamic carrying capacity and anti-deformation capacity of limestone is significant,which should be taken into account in practical engineering.关键词
灰岩/酸腐蚀/腐蚀时间/应变率/动态力学性能Key words
limestone/acid corrosion/corrosion time/strain rate/dynamic mechanical properties分类
建筑与水利引用本文复制引用
李光雷,蔚立元,靖洪文,苏海健,张涛,李明..酸腐蚀后灰岩动态压缩力学性质的试验研究[J].岩土力学,2017,38(11):3247-3254,8.基金项目
国家重点基础研究发展计划(973)项目(No.2013CB036003) （973）
国家自然科学基金(No.51579239,No.51374198).Supported by the National Key Basic Research and Development Program (973 Program) of China (2013CB036003) and The National Natural Science Foundation of China (51579239,51374198). （No.51579239,No.51374198）
