现浇空心楼板中无粘结预应力钢绞线应力增量研究
- 摘 要
-
刘昭清1,钱稼茹2,徐焱2(1 西南交通大学土木工程系, 成都 610031; 2 清华大学结构工程与振动教育部重点实验室, 北京 100084)[摘要]为研究现浇空心楼板中无粘结预应力钢绞线的应力增量,对一块四边简支、净跨为8m×8m的现浇预应力混凝土空心楼板进行了抗弯试验和有限元分析,采用国内外规范公式计算了该试验板预应力钢绞线的极限应力增量。结果表明,有限元计算得到的荷载\|预应力钢绞线应力增量关系与试验实测结果符合较好;规范JGJ 92—2004公式计算得到的预应力钢绞线极限应力增量不到试验实测值和有限元计算值的一半。建议空心楼板无粘结预应力钢绞线的极限应力增量可取JGJ 92—2004规定值的2倍。[关键词]现浇预应力混凝土; 空心楼板; 无粘结预应力钢绞线; 应力增量; 试验研究中图分类号:TU378文献标识码:A文章编号:1002848X(2013)06008204Investigation on stress increments of unbounded prestressed strands of castinsituconcrete hollow floor slabsLiu Zhaoqing1, Qian Jiaru2, Xu Yan2(1 College of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China;2 Key Laboratory forStructure Engineering and Vibration of Education Ministry, Tsinghua University, Beijing 100084, China)Abstract:To study the stress increments of the unbounded prestressed strands, bending test and finite element analysis of a 8m×8m castinsitu prestressed concrete hollow slab with four edges supported simply were carried out. The ultimate stress increment of the unbounded strands of the test slab was calculated by design codes. The results show that the loadstress increment relationship of strands calculated by the finite element analysis agrees well with the test curve. The ultimate stress increment obtained by JGJ 92—2004 is less than half of the test value. It is recommended that the ultimate stress increment of unbounded prestress strands can be two times of the value specified by JGJ 92—2004.Keywords:castinsitu prestressed concrete; hollow slab; unbounded prestressed strand; stress increment; experiment study作者简介:刘昭清,博士,工程师,Email:hands1224@163.com。参考文献[1]NAAMAN A E, ALKHAIRI F M. Stress at ultimate in unbounded posttensioning tendons:Part 2Porposed methodology [J]. ACI Structural Journal,1991, 88(6):683692.[2]杜拱辰,陶学康. 部分预应力混凝土梁无粘结筋极限应力的研究[J].建筑结构学报,1985, 6(6):213.[3]宋永发,王清湘,宋玉普,等.无粘结预应力双向板变形计算方法研究[J].大连理工大学学报,2001,41(5): 617620.[4]PARK R, GAMBE W L. 钢筋混凝土板[M]. 黄国祯,成源华,译.上海:同济大学出版社,1992.[5]房贞政. 无粘结与部分预应力结构[M]. 北京:人民交通出版社,1999.[6]JGJ 92—2004无粘结预应力混凝土结构技术规程[S]. 北京:中国建筑工业出版社,2004.[7]MSC. Software Corporation. Marc Volume A:Theory and user information [M]. 2005ed.U.S.A MSC. Software Corporation,2005.[8]郑文中,王晓东,王英. 现浇预应力混凝土梁板中无粘结筋应力增量极限值计算方法研究[C]//第十四届全国混凝土及预应力混凝土学术会议论文,2007:362383.[9]JGJ/T 92—93无粘结预应力混凝土结构技术规程[S]. 北京:中国建筑工业出版社,1993.[10]American Concrete Institute. Building Code Requirements for Structural Concrete (ACI 31802) and Commentary (ACI 31802)[S]. Michigan: ACI Committee 318,2002.[11] DIN 42272—1984. Prestressed concrete: partially prestressed structural members[S]. Deutsches Institut für Normung E.V., 1984.[12]BS 8110—1985 Code of practice for the structural use of concrete:Part 1:design, materials and workmanship[S]. British Standards Institute,1985.