池体筏板基础混凝土水化放热与温度应力分析  

Analysis on hydration heat and temperature stress of raft foundation concrete of tank body

作　　者：杨平[1] 王志强[1] 闫腾飞 陈保国[2] 张磊[2] YANG Ping;WANG Zhiqiang;YAN Tengfei;CHEN Baoguo;ZHANG Lei(Sinohydro Bureau 1 Co.,Ltd.,Chengdu 610081,Sichuan,China;Faculty of Engineeringy China University of Geosciences,Wuhan 430014,Hubei,China)

机构地区：[1]中国水利水电第七工程局有限公司,四川成都610081 [2]中国地质大学(武汉)工程学院,湖北武汉430074

出　　处：《工程建设》2021年第7期12-18,共7页Engineering Construction

基　　金：国家自然科学基金资助项目(51108434)。

摘　　要：大型池体现浇筏板基础易因水化放热引发温度裂缝问题。为了研究筏板基础水化放热温度变化规律及温度裂缝控制效果,本文以深圳市固戍水质净化厂二期地下综合体项目为依托,提出采用控制混凝土入模温度的方法来降低最高温度并控制温度裂缝产生,结合数值模拟与现场实测结果分析筏板基础水化放热规律和裂缝控制效果。结果表明:厚度为0.6 m的筏板基础混凝土在浇筑完1.5 d达到最高温度(56.29℃),混凝土内外温差为10.24℃,未产生温度裂缝;厚度为1.0 m的筏板基础混凝土在浇筑完2 d达到最高温度(66.8℃),内外温差为20.4℃,同时产生大面积温度裂缝。通过采取控制混凝土入模温度、积极养护等措施,降低最高温度峰值19%,且控制了混凝土温度裂缝的产生。The cast-in-place raft foundation of large tank body is easy to cause temperature cracks due to hydration heat.In order to study the variation law of hydration exothermic temperature of raft foundation and the effect of temperature crack control, the underground complex project of Shenzhen Gushu water purification plant phase II is taken as the support, the method of controlling the concrete entry mold temperature is proposed to reduce the maximum temperature and to control temperature cracks.Combined with the results of numerical simulation and field measurement, the hydration heat law and crack control effect of raft foundation are analyzed.The results show that: the raft foundation concrete with the thickness of 0.6 m reaches the highest temperature(56.29 ℃) on the first 1.5 days after pouring, and the temperature difference between the inside and outside of the concrete is 10.24 ℃.There is no temperature crack.The raft foundation concrete with the thickness of 1.0 m reaches the highest temperature(66.8 ℃) on the second day after pouring, and the temperature difference between inside and outside is 20.4 ℃.At the same time, a large area of temperature cracks are produced.By taking such measures as controlling the entry mold temperature of concrete and actively curing, the maximum temperature peak value is reduced by 19%,and the generation of concrete temperature cracks is controlled.

关 键 词：筏板基础 水化放热 温度裂缝 入模温度 数值模拟 

分 类 号：TU471.1+5[建筑科学—结构工程] TU755[建筑科学—土工工程]