不同加载速率下SAP混凝土断裂性能研究  

Fracture Performance of SAP Concrete under Different Loading Rates

作　　者：金子恒 谢发祥[1] 蔡定鹏 韩旭 掌昀 JIN Ziheng;XIE Faxiang;CAI Dingpeng;HAN Xu;ZHANG Yun(College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学土木与交通学院,南京210098

出　　处：《硅酸盐通报》2023年第10期3546-3553,共8页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金面上项目(51979090)。

摘　　要：为研究加载速率对高吸水性树脂(SAP)混凝土断裂性能的影响,本文浇筑了不同内养护水灰比SAP混凝土试件,采用三种加载速率开展缺口梁三点弯曲试验,测量和分析不同试件的断裂模式、裂纹开口位移和断裂韧性。试验结果表明:SAP混凝土和普通混凝土均具有应变率效应,且适量的SAP和内养护水可以提高混凝土的断裂能;随着内养护水灰比的增加,SAP混凝土的峰值强度比持续下降,起裂韧度和失稳韧度都呈逐渐降低的趋势;随着加载速率的增加,两种韧度都呈增长的趋势。本文提出的基于内养护水灰比和加载速率双因素影响的峰值强度比和断裂韧性拟合模型可为SAP混凝土在实际工程中的应用提供参考。In order to investigate the influence of loading rate on fracture performance of super absorbent polymer(SAP)concrete,the SAP concrete specimens with different water-cement ratios of internal curing were poured,and three-point bending test of notched beam with three loading rates was carried out.The fracture modes,crack mouth opening displacement and fracture toughness of specimens were measured and analyzed.The results reveal that SAP concrete and ordinary concrete all exhibit strain rate effect,and appropriate content of SAP and internal curing water can enhance the fracture energy of concrete.With the increase of water-cement ratio of internal curing,the peak strength ratio gradually decreases,and both the initiation toughness and unstable toughness show a decreasing trend.Conversely,as the loading rate increases,two toughness parameters exhibit an increasing trend.This study proposes a fitting model for the peak strength ratio and fracture toughness,considering the dual influence of the water-cement ratio of internal curing and the loading rate.The findings offer valuable insights for the practical application of SAP concrete in engineering project.

关 键 词：SAP 混凝土 内养护 三点弯曲试验 断裂能 断裂韧性 

分 类 号：TU528.1[建筑科学—建筑技术科学]