预应力空腹式钢骨混凝土梁徐变效应分析  

Creep effect analysis of lattice type prestressed steel reinforced concrete beam

作　　者：慕光波[1] 王连广[2] 

机构地区：[1]辽宁石油化工大学石油天然气工程学院,辽宁抚顺113001 [2]东北大学结构工程研究所,辽宁沈阳110004

出　　处：《混凝土》2010年第5期32-34,38,共4页Concrete

基　　金：辽宁省教育厅基金资助项目(2009A441)

摘　　要：根据截面内力平衡和应变协调条件,利用龄期调整有效模量法,建立预应力空腹式钢骨混凝土梁徐变效应分析模型,研制徐变效应分析计算程序,研究预应力空腹式钢骨混凝土梁在徐变效应影响下的应力重分布。计算结果表明:长期荷载作用下,梁受压区混凝土的压应力逐渐减少,上部角钢的压应力和下部角钢的拉应力逐渐增加,预应力筋的拉应力逐渐减少;跨中变形随着时间的增加而增大,直至趋于稳定;跨中变形的增量随混凝土强度、含钢率、轴力的增加而减小,随弯矩和混凝土保护层厚度的增加而增大。Considering the internal force equilibrium and strain harmony of the section,the creep effect of a lattice type prestressed steel rein- forced concrete beam is analyzed by use of age-adjusted-effective-modulus method.Furthermore,a program for creep effects is developed.And the stress redistribution of steel and concrete are studied too.The calculation results show that under long term loading pressure the compressive stress of compressive region of concrete and the tensile stress of tendon decrease gradually,and the pressure stress of upper angle steel and the tensile stress of downward angle steel increase gradually.Deformation of mid-span increases with the time and eventually reaches a constant.The incre- ment of the mid-span deformation decreases with the concrete strength,volumetric percentage of steel and axial force,and increases with the mo- ment and the thickness of the concrete covering layer.

关 键 词：预应力钢骨混凝土 徐变效应 应力重分布 变形 

分 类 号：TU528.01[建筑科学—建筑技术科学]