摘要
为了满足向家坝水电站大坝施工混凝土浇筑温度控制设计的需要,对向家坝水电站设计阶段的几种施工方案进行仿真模拟,研究其温度和温度应力场。主要对左岸的非溢流底孔两坝段、右岸的坝后厂房坝段、表孔坝段等典型坝段进行了仿真计算和温控方案研究。主要结论为:①基础强约束区最高温度为29.97℃,满足温控要求;基础弱约束区最高温度为38.04℃,所处位置材料为钢筋混凝土,可适当放宽容许温差。其它特征块的最高温度,均满足容许温差的要求。②基础强约束区顺河向最大应力为1.48 MPa,基础弱约束区顺河向最大应力为1.15 MPa,有较大的安全储备。③非孔洞区域典型点最小安全系数为3.02,在高程324.25 m附近,远大于抗裂安全系数1.65,温控防裂安全储备是足够的。④最大y方向温度应力出现在高程246.00 m位置,最大应力值为1.76 MPa,最大应力出现时恰逢全年最低温度,由此亦再次表明寒潮对表面应力影响很大,要注意做好坝体表面防寒工作。
In order to meet temperature control design of concrete grouting construction of Xiangjiaba hydropower station,in the light of several construction schemes in design stage of Xiangjiaba hydropower station,simulation analysis was carried out to research temperature and stress fields.The simulation computation and temperature control scheme research mainly aim at typical monoliths of 2 flowing bottom monoliths on left bank,power house monoliths behind dam,surface orifice monoliths etc.The main conclusion are: ① the maximum temperature of foundation strong constraint zone is 29.97 ℃,meeting temperature control requirement;the maximum temperature of foundation weak constraint zone is 38 ℃,due to the material in this zone is reinforced concrete,the tolerable temperature difference can be increased suitably;the maximum temperature of other typical blocks all meet tolerable temperature difference requirement.② the maximum stress of foundation strong constraint zone in river direction is 1.48 MPa,the maximum stress of foundation weak constraint zone in river direction is 1.15 MPa,having sufficient safety capacity.③ the minimum safety coefficient in non-orifice zone is 3.02,which is in the nearby of El.324.25 m,and much higher than anti-crack safety coefficient of 1.65,having sufficient safety capacity.④ the maximum temperature stress in y direction is 1.76 MPa at El.246,which takes place in minimum temperature duration in a year,this shows cold wave has large influence to surface stress,in the construction,cold-prevention for dam surface should be done well.
出处
《人民长江》
北大核心
2009年第11期20-23,共4页
Yangtze River
关键词
大体积混凝土
温度控制
一期管冷
后期管冷
大坝仿真
向家坝水电站
large volume concrete
temperature control
stage I pipe cooling
post pipe cooling
dam simulation
Xiangjiaba Hydropower Station
