超张拉理论在预应力渡槽裂缝处理中的应用  

Application of over-tensioning theory in the treatment of prestressed aqueduct cracks

作　　者：张涛 屈展 税创新 ZHANG Tao;QU Zhan;SHUI Chuangxin(Hubei Haoyuan Construction Engineering Co.,Ltd.,Yichang 433002,China;Yichang Dongfeng Canal Irrigation District Administration,Yichang 433002,China)

机构地区：[1]湖北昊源建设工程有限公司,湖北宜昌433002 [2]宜昌市东风渠灌区管理局,湖北宜昌433002

出　　处：《水利建设与管理》2022年第6期9-13,共5页Water Conservancy Construction and Management

基　　金：湖北省重点水利科研项目(HBSLKY201724)。

摘　　要：本文为解决简沟预应力渡槽裂缝问题,分析了加固材料与混凝土弹性模量不一致、应力松弛等因素,复核超张拉对结构影响。针对预应力渡槽梁体竖向的张性裂缝,提出“适度超张拉+灌缝封闭”的组合方案,有效解决了渡槽裂缝问题。适度超张拉不仅可削弱异弹模影响,还能减少张拉初期应力松弛,强化预应力混凝土开裂部位,保持其完整性和稳定性,为类似工程提供了新的思路。This paper mainly analyzes the causes of cracks in the prestressed structure of Jiangou aqueduct and compares the reinforcement schemes.Analyze the influence of inconsistent elastic modulus and stress relaxation between reinforcement materials and concrete,and recheck the influence of over tensioning on the structure.Aiming at the vertical tensile cracks of prestressed aqueduct beam,a combined scheme of moderate over tensioning+grouting joint closure is innovatively proposed.Moderate over tensioning can not only weaken the influence of different elastic modulus,but also reduce the stress relaxation at the initial stage of tensioning,strengthen the cracking part of prestressed concrete and maintain its integrity and stability,and provides a new idea for similar projects.

关 键 词：超张拉 预应力渡槽 裂缝处理 

分 类 号：TV554[水利工程—水利水电工程]