引江济淮大型泵站施工期结构开裂特性与防裂措施影响研究

Crack characteristics and prevention measures of large pump stations in Yangtze River to Huaihe River Diversion Project during construction

摘要

引江济淮工程泵站为满足大流量输水要求，多设计成超长、大整浇结构，使得温控防裂难度要远大于其他引调水泵站工程。为深入探究这种无缝整浇式大型泵站的施工期温度应力演化规律及开裂特性，论证可操行强且经济合理的温控防裂措施可行性。选取引江济淮枞阳泵站为研究对象，基于施工期浇筑过程有限元仿真计算，模拟真实环境、材料、结构、多种温控措施的影响，分析结构施工期温度场、应力场以及开裂风险。结果表明，进水流道层超长底板、厚边墙、上游挡水墙是结构防裂的重点，施工期拉应力多在2.0~3.0 MPa,超过混凝土的允许抗拉强度；通过采用表面保温、通水冷却以及控温浇筑等多措并举且分区差异性控制的方法，能够大大降低其开裂风险。因地制宜的温控防裂措施可行，可为其他引调水工程大型整浇泵站结构防裂设计提供参考。

Abstract

To meet the requirements of water conveyance, pumping stations in the Yangtze River to Huaihe River Project are designed with ultra long and large integral pouring structures, making temperature control and crack prevention much more difficult than other water diversion pump station projects. In order to explore the temperature stress and cracking characteristics during the construction of this seamless pumping station, the feasibility for crack prevention measures with easy operation and reasonable temperature control are demonstrated. Selecting the Zongyang Pumping Station as the research object, based on finite element simulation calculation of pouring process during construction, considering the influence of real environment, materials, structure, and various temperature control measures, the temperature and stress field, crack risk are analyzed. The result show that the ultra long bottom plate, thick side wall and upstream wall of the inlet channel layer are the key points for structure crack prevention; the tensile stress is mostly between 2.0 MPa and 3.0 MPa, exceeding the allowable tensile strength of concrete during construction; By adopting a combination of surface insulation, water cooling and temperature control pouring with differentiated control, the risk of cracking can be greatly reduced. The temperature control and crack prevention measures tailored to local conditions are feasible, which can provide reference for the structure crack prevention design of integral pouring pump stations in other water diversion projects.

关键词

整浇式泵站 / 温度应力仿真 / 开裂风险 / 差异化温控

Key words

integral pump stations / temperature stress simulation / crack risk / differentiating control temperature

Author summay

陈正旵(1972—)男, 高级工程师, 学士, 主要从事交通土建工程工作。E-mail: [e-mail]

基金资助

国家自然科学基金资助项目(52009011)

安徽省引江济淮集团有限公司科技项目(YJJH-ZT-ZX-20190823179)