聚合物水泥基复合填缝料浸水后剪切性能  

Shear performance of polymer cement-based composite joint sealant after immersion in water

作　　者：王志航 白二雷[1] 许金余[1,2] 刘高杰 朱从进 WANG Zhihang;BAI Erlei;XU Jinyu;LIU Gaojie;ZHU Congjin(School of Aviation Engineering,Air Force Engineering University,Xi′an 710038,China;College of Mechanics and Civil Architecture,Northwest Polytechnic University,Xi′an 710072,China;The Third Bureau of China Maritime Police Bureau,Guangzhou 510006,China;Unit 94921,People's Liberation Army of China,Jinjiang 362200,China)

机构地区：[1]空军工程大学航空工程学院,陕西西安710038 [2]西北工业大学力学与土木建筑学院,陕西西安710072 [3]中国海警局直属第三局,广东广州510006 [4]中国人民解放军94921部队,福建晋江362200

出　　处：《中南大学学报（自然科学版）》2021年第7期2416-2425,共10页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51208507,51378497)。

摘　　要：针对机场道面填缝料承受剪切荷载与面临浸水作用的实际工作环境,对聚合物水泥基复合填缝料(PCJS)进行浸水试验、干湿循环试验和剪切试验,测试剪切强度、剪切韧度、峰值应变和断裂伸长率等指标,研究PCJS浸水后的剪切性能。结合SEM与MIP试验结果,分析不同浸水时间和干湿循环次数对PCJS微观形貌和孔隙结构的影响。研究结果表明:PCJS持续浸水后剪切性能劣化,浸水1 d时剪切强度损失率为6.64%,剪切韧度保持率为91.14%,峰值应变和断裂伸长率分别增大了11.73%和14.32%。PCJS干湿循环次数较少时(5次和10次),剪切性能优化,当干湿循环次数较多时(15次和20次),剪切性能劣化;水分子促使PCJS内部分子结构发生降解断裂和未水化的水泥发生二次水化反应。持续浸水和干湿循环导致PCJS的微观形貌劣化,裂缝增加,大孔增多,剪切性能劣化;当干湿循环较少时,使得PCJS孔径分布更均匀,平均孔径减小,剪切性能优化。Aiming at the actual working environment where the airport pavement joint sealant was subjected to shear load and facing water immersion,the polymer-cement based composite joint sealant(PCJS)was subjected to water immersion test,dry and wet cycle test and shear test,and by testing the shear strength,shear toughness,peak strain and elongation at break,the shear performance of PCJS after immersion in water was studied.Combined with the results of SEM and MIP experiments,the effects of different immersion time and the number of wet and dry cycles on the microscopic morphology and pore structure of PCJS were analyzed.The results show that the shear performance of PCJS deteriorates after continuous immersion in water.When the immersion time in water is 1 d,the shear strength loss rate is 6.64%,the shear toughness retention rate is 91.14%,and the peak strain and elongation at break increase by 11.73%and 14.32%respectively.When the number of PCJS wet and dry cycles is small(5 times and 10 times),the shear performance is optimized,and when the number of wet and dry cycles is large(15 times and 20 times),the shear performance is deteriorated.Water molecules promote degradation and fracture of the internal molecular structure of PCJS and secondary hydration of unhydrated cement.Continuous water immersion and dry-wet cycles lead to deterioration of PCJS's microscopic appearance,increased cracks,increased macropores,and degraded shear performance.When there are fewer dry-wet cycles,the PCJS pore size distribution is more uniform,the average pore size is reduced,and the shear performance is optimized.

关 键 词：填缝料 复合材料 浸水 剪切 

分 类 号：TU528[建筑科学—建筑技术科学]