养护制度对超高性能混凝土高温损伤后残余力学性能的影响  

EFFECT OF CURING SYSTEM ON RESIDUAL MECHANICAL PROPERTIES OF ULTRA-HIGH PERFORMANCE CONCRETE EXPOSED TO ELEVATED TEMPERATURE

作　　者：欧阳利军[1] 钱鹏 高皖扬 丁斌[3] 王庆 OUYANG Lijun;QIAN Peng;GAO Wanyang;DING Bin;WANG Qing(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;School of Naval Architecture,Ocean&Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Wenzhou Vocational&Technical College,Wenzhou 325035,China)

机构地区：[1]上海理工大学环境与建筑学院,上海200093 [2]上海交通大学船舶海洋与建筑工程学院,上海200240 [3]温州职业技术学院建筑工程系,浙江温州325035

出　　处：《工业建筑》2020年第8期92-100,共9页Industrial Construction

基　　金：国家自然科学基金项目(51708349,11672185);温州市科技局基础性科研项目(G20180028)。

摘　　要：对48个超高性能混凝土(UHPC)立方体抗压试件采用洒水养护、热水养护、洒水-干热养护和热水-干热养护,对18个UHPC哑铃形抗拉试件进行热水养护和热水-干热组合养护,养护完成后分别测定抗压试件和抗拉试件高温作用后的残余抗压强度和残余抗拉强度。结果表明:采用洒水-干热(105℃)组合养护和热水-干热组合养护的立方体试件分别在348,370℃的高温作用下发生爆裂,且这两种组合养护方式下的试件抗压强度相较于单一洒水养护和单一热水养护方式下的分别降低36.73%和14.56%。采用洒水-干热(200℃)组合养护的立方体试件残余抗压强度随着目标温度的增加呈先上升后下降的趋势,临界温度为300℃,该养护方式不仅提高了UHPC的高温残余抗压强度,同时立方体试件均未发生爆裂。采用热水-干热(105℃)养护的哑铃型试件残余抗拉强度随目标温度的提升呈先上升后下降的趋势,该组合养护方式下试件的抗拉强度仅为热水养护的54.05%,当目标温度超过400℃时,哑铃型试件发生爆裂。Axial compressive tests were conducted on 48 UHPC(ultra-high performance concrete)cubes cured under sprinkler curing,hot water curing,sprinkler-dry air combined curing,and hot water and dry air combined curing respectively to investigate residual compressive strength of heat-damaged.Axial tensile tests were conducted on 18 dumbbell-shaped specimens cured under hot water curing and hot water and dry air combined curing respectively to investigate the residual tensile strength.The test results showed that compared with the corresponding mono-curing regime,the compressive strength of the specimens subjected to sprinkling-dry air(105℃)combined curing and hot water and dry air(105℃)combined curing decreased by 36.73%and 14.56%,respectively,and spalled at the temperature of 348℃and 370℃,respectively.The residual compressive strength of UHPC subjected to sprinklingdry air(200℃)curing regime increased at first and then decreased during the increase of temperature,and the critical temperature was 300℃,at which showed the best explosive spalling resistance performance.Residual axial tensile strength of specimen subjected to hot water and dry air(105℃)curing also increased firstly and then decreased with the increasing temperature,the axial tensile strength cured under hot water and dry air(105℃)curing was only 54.05%of that under hot water curing.The dumbbell-shaped specimens could not avoid the occurrence of explosive spalling when the temperature was over 400℃.

关 键 词：超高性能混凝土 养护制度 残余抗压强度 残余抗拉强度 高温爆裂 

分 类 号：TU528[建筑科学—建筑技术科学]