大型渡槽结构运行期保温设计研究  

Research on Thermal Insulation Design of Large Aqueduct Structure During Operation

作　　者：李国会 卢玲 李海枫[3] LI Guohui;LU Ling;LI Haifeng(Hunan Polytechnic of Water Resources and Electric Power,Changsha 410131,China;Yellow River Engineering Consulting Co.,Ltd.,Zhengzhou 450003,China;China Institute of Water Resources and Hydropower Research,Beijing 100038,China)

机构地区：[1]湖南水利水电职业技术学院,湖南长沙410131 [2]黄河勘测规划设计研究院有限公司,河南郑州450003 [3]中国水利水电科学研究院,北京100038

出　　处：《人民黄河》2023年第12期152-156,共5页Yellow River

基　　金：犬木塘水库工程科技创新项目(湘水集[2022]47号);国家重点研发计划项目(2016YFC0401807)。

摘　　要：渡槽属于典型空间薄壁结构,对外界温度变化很敏感,采取表面保温措施可有效改善槽身结构温度应力分布进而防止表面裂缝产生。目前,坝工领域中常用的表面保温能力计算方法对渡槽保温问题虽然具有借鉴意义但不可直接套用,故渡槽保温问题需要单独研究。为此,从渡槽结构温度荷载出发,提出一个基于混凝土结构温度及温度应力分析的渡槽保温设计计算方法。以某U形渡槽为例进行分析,结果表明:在槽身直墙段与圆弧段0~45°的外表面铺设5.0 cm厚聚氨酯泡沫塑料保温材料后,槽身应力状态得到较大改善,温升时内壁环向和纵向均不出现拉应力,温降时外壁环向和纵向应力较未设置保温措施时有所降低,槽身内外壁应力状态满足设计规范要求。工程案例研究的保温设计计算方法可用于渡槽运行期保温设计,进而确定铺设范围及保温层厚度等保温设计关键参数。Aqueduct is a typical space thin-walled structure,which is very sensitive to external temperature changes.Surface insulation measures can effectively improve the temperature stress distribution of the structure and prevent surface cracks.Although the calculation method of surface insulation capacity commonly used in dam construction is of reference significance to aqueduct insulation issue,it cannot be directly applied,so the aqueduct insulation issue needs to be studied separately.Therefore,based on the temperature load of aqueduct structure,this paper put forward a calculation method of aqueduct insulation design based on the temperature and temperature stress analysis of concrete structure.The calculation results show that the stress state of the groove body can be greatly improved by laying 5.0 cm thick polyurethane foam insulation material on the outer surface of the straight wall section and the arc section of 0°-45°.When the temperature rises,the inner wall circumferential and longitudinal tensile stress does not appear.When the temperature drops,the circumferential and longitudinal stress of the outer wall is reduced,and the stress state of the inner and outer walls of the groove body meets the design requirements.The project case study shows that the calculation method of thermal insulation design proposed in this paper can be applied to the thermal insulation design of aqueduct during operation,and then the key parameters of thermal insulation design such as laying range and insulation layer thickness can be determined.

关 键 词：渡槽 温度荷载 保温设计 保温效应模拟 

分 类 号：TV672.3[水利工程—水利水电工程]