百米级超长预应力束张拉试验研究  

Experimental Study on Tension of Hectometer-ultra-long Prestressed Tendons

作　　者：端茂军[1] 魏洋[1] 杨欧峰 李国芬[1] 

机构地区：[1]南京林业大学土木工程学院,江苏南京210037

出　　处：《公路工程》2016年第3期31-34,39,共5页Highway Engineering

基　　金：国家自然科学基金(51208262);江苏高校优势学科建设工程资助项目(PAPD);住房和城乡建设部科学技术项目(2011-K2-9)

摘　　要：以常州市S122省道长江路上跨桥为研究对象,通过现场试验,研究百米级超长预应力束的初始张拉力及持荷时间,根据孔道摩阻试验得出孔道摩阻系数对理论模型进行检算。结果表明,100 m级超长预应力束的初始张拉力宜取张拉控制力的30%,持荷时间宜取6~8 min,孔道摩阻系数较规范值大,造成结构挠度增大及混凝土应力储备减小,但仍在规范允许范围之内,实测孔道摩阻系数对超长束的设计及施工具有重要参考价值。With the study of viaduct across the Changjiang Road in S122 provincial highway in Changzhou,the initial tension and loading duration of hectometer-ultra-long prestressed tendons were researched based on the field test,from which the channel friction coefficient used to check the theoretical model was achieved. The results indicate that the initial tension value of hectometer-ultra-long prestressed tendons should be 30% of the control stress for prestressing and the loading duration should be 6 ~ 8 minutes. Although the channel friction coefficient is beyond the code value which causes the increasement of structure deflection and decreasement of stress reserve of concrete,it is still within permissible range of the code,the measured channels friction coefficient value is significantreference for design and construction of ultra-long prestressed tendons.

关 键 词：百米级 超长预应力束 初始张拉力 持荷时间 孔道摩阻试验 

分 类 号：U448.215[建筑科学—桥梁与隧道工程]