钢管煤矸石混凝土的徐变模型及长期变形计算方法  

Creep Model and Long-term Deformation Calculation Method of Coal Gangue Aggregate Concrete Filled Steel Tubes(CGACFST)

作　　者：王庆贺 张岩[1] 张玉琢 张信龙 岳崇 WANG Qinghe;ZHANG Yan;ZHANG Yuzhuo;ZHANG Xinlong;YUE Chong(School of Civil Engineering,Shenyang Jianzhu University,Shenyang,China,110168;Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education,Harbin Institute of Technology,Harbin,China,150090;China Construction Second Engineering Bureau Ltd,Beijing China,100000)

机构地区：[1]沈阳建筑大学土木工程学院,辽宁沈阳110168 [2]哈尔滨工业大学结构工程灾变与控制教育部重点实验室,黑龙江哈尔滨150090 [3]中国建筑第二工程局有限公司,北京100000

出　　处：《沈阳建筑大学学报（自然科学版）》2023年第4期651-659,共9页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(51808352);辽宁省应用基础研究计划项目(2022JH2/101300130);辽宁省教育厅科研项目(lnjc202007);沈阳市中青年科技人才项目(RC200143);住房和城乡建设部科学技术计划项目(2019-K-054)。

摘　　要：目的为促进煤矸石在混凝土中的应用,对钢管煤矸石混凝土的徐变性能和长期力学性能进行深入研究。方法基于Bazant徐变模型提出考虑煤矸石取代率和粗骨料体积分数综合影响的煤矸石混凝土徐变模型,进而采用逐步积分法与基于龄期调整的有效模量法研究钢管煤矸石混凝土长期性能。结果50%取代率的煤矸石混凝土较普通混凝土徐变系数增幅在10%以内,100%取代率的煤矸石混凝土增幅约为30%;相对湿度由30%增至80%时,徐变系数降低约40%;抗压强度由30 MPa增至60 MPa时,徐变系数降低约40%;构件厚度达到500 mm以后,对徐变系数影响不显著;基于龄期调整的有效模量法与逐步积分法预测结果差异在10%以内。结论煤矸石混凝土的徐变系数与取代率呈正相关,与环境相对湿度、抗压强度、砂率、构件尺寸呈负相关,外部钢管可有效降低煤矸石混凝土的徐变变形;基于龄期调整的有效模量法能够快速准确地预测钢管煤矸石混凝土柱的长期变形。To promote the application of coal gangue aggregate concrete(CGAC),a research is conducted on the creep properties and long-term deformation calculation method of coal gangue aggregate concrete filled steel tubes(CGACFST).A CGAC creep model considering the combined effects of coal gangue aggregate(CGA)replacement ratio and coarse aggregate volume content was proposed following the Bazant creep model.The long-term performance of CGACFST was predicted by the step-by-step method(SSM)and age-adjusted effective modulus method(AEMM).The results show that Compared with natural concrete,the creep coefficient of CGAC with 50%CGA increased by about 10%;the creep coefficient of CGAC with 100%CGA increased by about 30%.With an increase in relative humidity from 30%to 80%,the creep coefficient decreases by approximately 40%.With an increase in compressive strength from 30 MPa to 60 MPa,the creep coefficient decreases by approximately 40%.The influence on the creep coefficient becomes insignificant after the theoretical thickness reaches 500 mm.The creep coefficient of CGAC increased with the CGA replacement ratio,decreased with relative humidity,compressive strength,sand ratio,theoretical thickness;The creep deformation of CGAC can be effectively reduced due to the outer steel tube.Using the AEMM to predict the long-term deformation of the CGAC-filled steel tube was sufficiently accurate,and the maximum difference between AEMM and SSM of 10%.

关 键 词：钢管混凝土 煤矸石混凝土 徐变 取代率 预测方法 

分 类 号：TU398[建筑科学—结构工程]