冲击荷载下盐腐蚀水泥砂浆接触损伤研究  

Study on Mechanism of Contact Damage of Salt Corroded Cement Mortar under Impact Load

作　　者：郝贠洪[1,2] 韩燕[1] 樊磊 樊金承 杨晓明[1,2] HAO Yunhong;HAN Yan;FAN Lei;FAN Jincheng;YANG Xiaoming(School of Civil Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;Inner Mongolia Key Laboratory of Civil Engineering Structures and Mechanics,Inner Mongolia University of Technology,Hohhot 010051,China)

机构地区：[1]内蒙古工业大学土木工程学院,内蒙古呼和浩特010051 [2]内蒙古工业大学内蒙古自治区土木工程结构与力学重点实验室,内蒙古呼和浩特010051

出　　处：《铁道学报》2018年第10期144-151,共8页Journal of the China Railway Society

基　　金：国家自然科学基金(51468049;11662012)

摘　　要：利用冲击球压法研究标准养护条件和不同盐腐蚀环境(5%NaCl溶液、5%Na_2SO_4溶液和5%NaCl与Na_2SO_4混合溶液)下水泥砂浆受冲击荷载作用的表面损伤失效规律及损伤叠加效应。结果表明:盐腐蚀下水泥砂浆遭受小能量冲击时,表面损伤区压痕尺寸随冲击荷载值增加呈先快速后平缓的增长趋势,试样表面损伤越严重,压痕增长越快;在相同冲击荷载作用下,水泥砂浆表面力学性能指标(动态硬度值和恢复性系数)从高到低依次为标准养护砂浆、5%NaCl溶液中砂浆、5%NaCl与Na_2SO_4混合溶液中砂浆、5%Na_2SO_4溶液中砂浆;在冲击荷载作用下,短期盐腐蚀砂浆试样表面颗粒剥落,微裂纹不断扩展并合,损伤区三维形貌参数均大于标准养护砂浆。本文研究成果可为冲击荷载与腐蚀离子双因素作用下铁路桥梁工程材料的耐久性研究提供依据。Spherical pressure tests were used to study the surface damage and failure regularity and damage superposition effect of the cement mortar subjected to impact loading,under standard curing conditions and different salt corrosion environment(5%NaCl solution,5%Na 2SO 4 solution and 5%NaCl and Na 2SO 4 composite solution).The results show that when the cement mortar is subjected to small energy impact under salt corrosion,the indentation size in the surface damage area shows a trend of rapid increase first and slow increase later along with the increase of the impact load value.The more serious the specimen surface damage is,the faster the indentation growth rate will be.Under the same impact load,the surface mechanics performance index rank(from high to low)of the cement mortar is standard curing,5%NaCl solution,5%NaCl and Na 2SO 4 composite solution,5%Na 2SO 4 solution.Under the impact load,the particles of the surface of the short-term salt corroded mortar are peeled off,and the micro cracks continue to expand.The 3D shape parameters of the damage zone are larger than those of the mortar under standard curing.The research results will provide a basis for the durability study of railway bridge construction materials under the double factors of load and corrosion.

关 键 词：水泥砂浆 盐腐蚀 冲击作用 接触损伤 

分 类 号：TU502[建筑科学—建筑技术科学] TQ172.71[化学工程—水泥工业]