受酸腐蚀砂岩力学性质及孔隙结构变化研究  

Mechanics Properties and Pore Structure Change of Acid-corroded Sandstone

作　　者：霍润科[1] 王国杰 李曙光[1] 任振中 韩飞 HUO Run-ke;WANG Guo-jie;LI Shu-guang;REN Zhen-zhong;HAN Fei(School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学土木工程学院

出　　处：《长江科学院院报》2019年第12期96-101,106,共7页Journal of Changjiang River Scientific Research Institute

基　　金：国家自然科学基金项目(41172237);陕西省教育厅专项基金项目(11JK0947)

摘　　要：为研究酸性环境下砂岩的力学性质以及孔隙结构的变化,对酸液腐蚀后的砂岩进行了单轴压缩试验和孔隙率的计算,探讨了腐蚀时间和酸液浓度对砂岩力学参数和孔隙率的影响。结果表明:酸性溶液对砂岩腐蚀情况显著,浸泡后,砂岩孔隙率增大,电镜扫描图孔隙面积明显增加,且溶液浓度越大,腐蚀时间越长,孔隙体积越大;受酸腐蚀砂岩单轴抗压强度和弹性模量降低显著,试验结束后,pH=1硫酸溶液和pH=3硫酸溶液砂岩单轴抗压强度分别降低31.59%和26.99%,弹性模量分别降低64.46%和62.26%;基于次生孔隙率,构建化学损伤变量,并建立了化学损伤变量同力学参数的关系式;砂岩力学参数的降低与次生孔隙率的变化具有较好的一致性。In the aim of obtaining the changes in mechanical properties and porosity of sandstone in acid environment,we examined the influences of corrosion time and acid concentration on sandstone’s mechanics properties and porosity through uniaxial compression test on acid-corroded sandstone.Results revealed an apparent corrosion effect on sandstone.The porosity of sandstone soaked in acid solution increased,as reflected by an evident expansion of porosity area in SEM images;the volume of porosity is in positive relation with acid concentration and corrosion time.Moreover,the uniaxial compressive strength and elastic modulus of sandstone deteriorated remarkably after acid corrosion.The uniaxial compressive strength of sandstone corroded by pH=1 sulfuric acid solution and pH=3 sulfuric acid solution decreased by 31.59%and 26.99%,respectively,and the elastic modulus reduced by 64.46%and 62.26%,respectively.In addition,the relation between chemical damage variable based on secondary porosity and mechanics parameters was established;the deterioration of mechanical parameters of sandstone is consistent with the change of secondary porosity.

关 键 词：砂岩 水岩化学反应 孔隙率 化学损伤 腐蚀机制 单轴抗压强度 弹性模量 

分 类 号：TU458.3[建筑科学—岩土工程]