摘要
预应力钢筒混凝土管(PCCP)的承载能力计算涉及管芯开裂时的弯矩重分布,是管体结构设计的重要组成部分。本文针对现有计算方法中管芯开裂判定的经验性和现有试验结果中管芯开裂后管体变形的剧烈性问题,提出了三边承载试验下PCCP承载能力计算模型。模型基于刚性管假设推导了管壁截面的弯矩与轴力系数,采用简化的混凝土应力应变关系作为管芯开裂的判别标准,给出管芯开裂后的管腰处弯矩重分布和管顶(底)处轴力作用线移动的数学表达,开展了基于分布式光纤传感器测量的三边承载试验,并验证了计算方法的合理性。对比验证结果表明,管芯开裂前计算与试验结果基本一致,管芯开裂后计算与实测结果在趋势上相同。本文采用的计算模型与原型试验的对比分析框架,有助于更深入了解PCCP受载变形规律,并在未来用于管体设计参数的确定与优化。
The calculation of bearing capacity for prestressed concrete cylinder pipe(PCCP)involves the redistribution of bending moment when the core cracks,which is an important component in the design of pipe structures.To address the empirical nature of core cracking determination in existing calculation methods and the severity of pipe deformation after core cracking in existing experimental results,a PCCP bearing capacity calculation model under three-edge bearing test is proposed.The model derives the bending moment and thrust coefficients of the pipe wall section based on a rigid pipe assumption and uses the simplified stress-strain relationship of concrete as a criterion for determining core cracking.After core cracking,mathematical expressions for the redistribution of bending moment at the springline and the movement of the action line of thrust at the invert(crown)are given.A three-edge bearing test based on distributed optical fiber sensors were conducted to verify the rationality of the calculation method.Comparative verification results show that calculated results are consistent with experimental results before core cracking,while they have similar trends after core cracking.The comparative analysis framework between the calculation model and prototype experiment helps deepen our understanding of PCCP deformation laws under external loads and will be useful in determining and optimizing pipe design parameters in future applications.
作者
窦铁生
董晓农
董鹏
李炎隆
宁靖华
黎康平
DOU Tiesheng;DONG Xiaonong;DONG Peng;LI Yanlong;NING Jinghua;LI Kangping(State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China;Hanjiang-to-Weihe River Valley Water Diversion Project Construction Co.,Ltd.,Xi’an 710010,China;State Key Laboratory of Eco-hydraulics in Northwest Arid Region,Xi’an University of Technology,Xi’an 710048,China;Powerchina Shandong Pipeline Engineering Corporation Limited,Jinan 250117,China)
出处
《中国水利水电科学研究院学报（中英文）》
北大核心
2024年第6期558-569,共12页
Journal of China Institute of Water Resources and Hydropower Research
基金
水利部重大科技项目(SKS-2022111)
陕西省自然科学基础研究计划项目(2019JLZ-14)。
关键词
PCCP
计算模型
三边承载试验
分布式光纤传感器
设计参数优化
PCCP
calculation model
three-edge bearing test
distributed optical fiber sensors
optimization of design parameters
