超高韧性水泥基复合材料抗压性能的尺寸效应研究  

The size effect of compressive properties of Ultra High Toughness Cementitious Composites(UHTCC)

作　　者：李庆华[1] 周宝民[1] 黄博滔[1] 徐世烺[1] 应建坤 

机构地区：[1]浙江大学高性能建筑结构与材料研究所,浙江杭州310058

出　　处：《水利学报》2015年第2期174-182,共9页Journal of Hydraulic Engineering

基　　金：国家自然科学基金资助项目(51008270;51378462)

摘　　要：超高韧性水泥基复合材料(Ultra High Toughness Cementitious Composites,简称UHTCC)是一种具有超高韧性和良好耐久性能的新型混凝土材料,能够有效控制水工结构中有害裂缝的发生,提高结构耐久性。本文对标准立方体和4组不同高厚比UHTCC棱柱体试件的压缩性能进行了试验研究,得到了受压应力-应变全曲线。结果表明,UHTCC抗压性能的尺寸效应规律有别于普通混凝土。抗压峰值应变(名义应变)与真实应变关系紧密,具有近似的比例关系;高厚比大于1时,高厚比对UHTCC棱柱体强度影响不大,有别于普通混凝土棱柱体试验结果;高厚比对UHTCC棱柱体峰值应变有较大影响,在一定程度上反映了环箍效应的作用。最后,在试验结果与分析的基础上提出了一个适用于不同高厚比的UHTCC压缩应力-应变模型。Ultra High Toughness Cementitious Composites（UHTCC） is a new type of concrete materialswith high toughness and good durability. It can do well in controlling harmful cracks used in HydraulicStructure and improve the durability of the structure. In this paper,the size effect of compressive proper-ties of UHTCC has been discussed. During the test,experiments were carried out on UHTCC prism withdifferent height-thickness ratio. The complete compressive stress-strain curves for different ratio of height tothickness have been obtained. Experimental results show that there is an approximate proportional relation-ship between the compressive peak strain（nominal strain） and the true strain. Different from ordinary con-crete prism test results,the ratio of height to thickness has little effect on the strength of UHTCC prism.However,the height-thickness ratio has a great influence on the peak strain of UHTCC prism,which re-flects the action of the hoop effect. Finally,based on the experimental results and analysis,we propose acompressive stress- strain model,applying to different height-thickness ratio.

关 键 词：UHTCC 尺寸效应 高厚比 峰值应变 应力-应变模型 

分 类 号：TU528.44[建筑科学—建筑技术科学]