摘要
PCCP是由混凝土管芯、钢筒、预应力钢丝以及砂浆保护层构成的复合结构,不但承受内水荷载,还有外部土荷载、管体自重与水重、活荷载以及临时堆土等外荷载作用,在外荷载作用下PCCP的变形规律与内荷载的变形规律完全不同。为研究PCCP在极限外荷载作用下的变形规律,在国内外首次采用BOTDA和FBG光纤传感技术,并将光纤在PCCP制造过程中植入钢筒表面,采用三点试验法对内径2.6 m埋置式PCCP原型管进行了外荷载试验,在加载过程中连续测试PCCP各层结构的应变响应。通过深入分析测试数据发现,在三点法试验加载过程中,管体结构各层材料的变形与外荷载正比相关,钢筒外侧管芯混凝土与钢丝的变形协调一致,钢筒内侧管芯混凝土与钢筒的变形基本协调一致。管腰处管芯混凝土外侧和钢丝受拉,管腰处管芯混凝土内侧和钢筒受压,管顶和管底则与之相反,但变形协调规律一致。外荷载原型试验获得了PCCP各层结构受载响应规律,为PCCP结构深层次的基础理论研究和工程应用提供了宝贵的试验资料。
PCCP is a composite structure composed of concrete core, steel cylinder, prestressed wire and mortar coating, it is not only withstanding the internal water pressure, but also hearing the external load including the tube body weight, soil and water weight, live load and load from pile soil temporarily, the de- formation law of PCCP under external load and the deformation law of PCCP under the internal load is completely different. The test used BOTDA and FBG optical fiber sensor technology for the first time both at home and aboard, and the optical fiber implanted steel cylinder surface in the PCCP manufacturing pro- cess. A three-edge bearing test was carried out on 2.6 m diameter embedded PCCP （ECP）, continuously tested the strain response of PCCP each layer structure in the process of loading. Through in-depth analy- sis of test data, it is found that in the loading process of the three-edge test, the deformation of PCCP each layer structure is proportional to the external load, the concrete core outside of cylinder are in harmo- ny with the wire in deformation, the deformation between the concrete core inside of the cylinder and the cylinder are coordinated fundamentally. The outer concrete core at the pipe waist and the wire are in ten- sion, the inner concrete core at the pipe waist and the wire are in compression, concrete core at invert and crown is opposite, but the law of deformation coordination is consistent. The prototype test of external load not only obtained the loading response law of the PCCP layers structure, but also provided valuable experimental data for deeply basic theoretical research and engineering application of PCCP structure.
作者
窦铁生
程冰清
胡赫
夏世法
杨进新
张奇
DOU Tieshengl, CHENG Bingqing1, HU He1, XIA Shifa1, YANG Jinxin2, ZHANTG Qi2(1. State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; 2. Beijing Institute of Water, Beij＇ing 100044, Chin)
出处
《水利学报》
EI
CSCD
北大核心
2018年第2期207-215,共9页
Journal of Hydraulic Engineering
基金
国家自然科学基金项目(50979116)
北京市科委重大专项课题(Z141100006014058)
关键词
预应力钢筒混凝土管
三点试验法
BOTDA
FBG
承载力
prestressed concrete cylinder pipe
three-edge bearing test method
BOTDA
FBG
bearing capacity
