摘要
顶管在顶进过程中发生的失稳破坏已严重威胁工程的安全施工。以中交二公局第四工程有限公司承担的石岩北清污分流钢顶管工程项目为依托,基于薄壁圆柱壳屈曲理论,通过改变长细比、径厚比和埋深等影响因素对大直径钢顶管应力、屈曲模态和屈曲荷载进行分析。分析结果表明:钢顶管稳定性随长细比(顶管长度与管道外径的比值)的增加而减小,长细比<30(短顶管),易发生局部屈曲破坏,长细比>30(长顶管),易发生整体失稳破坏;在均布围压作用下,钢顶管屈曲模态以局部屈曲为主,其稳定性随径厚比的增加而减小;钢顶管实际稳定系数随埋深变化由管周围压和椭圆化变形共同决定。基于以上分析结果,提出了大直径钢顶管稳定性系数经验公式,结合工程实例进行验证,具有良好的指导意义。
The instability of the pipe jacking has threatened the safe construction of the project seriously during the jacking process. The research was based on the Shiyanbei sewage diversion steel pipe jacking project, which was undertaken by the Fourth Engineering Co., Ltd. of China Communications Second Highway Bureau. Based on the buckling theory of thin-walled cylindrical shells, the stress, buckling mode and buckling load was analyzed by changing the influencing factors such as slenderness ratio, diameter-thickness ratio and buried depth. The research results show that the stability of steel pipe jacking decreases with the increase of slenderness ratio(the ratio about the length of the jacking pipe to the outer diameter of the pipe). When the slenderness ratio <30(short jacking pipe), local buckling failure is prone to occur. However when the slenderness ratio >30(long jacking pipe), the overall instability failure is prone to occur. Under distributed confining pressure, the buckling mode of steel pipe jacking is dominated by local buckling, and its stability decreases with the increase of the diameter-to-thickness ratio. The actual stability coefficient is determined by the pressure around the pipe and the elliptical deformation, which varies with the buried depth. Based on the above analysis results, an empirical formula was proposed about the stability coefficient of large-diameter steel pipe jacking. It has been verified by engineering examples and has good guiding significance.
作者
荆哲
房鹏帅
张耀阳
李文杰
梁斌
JING Zhe;FANG Peng-shuai;ZHANG Yao-yang;LI Wen-jie;LIANG Bin(CCCC-SHEC Forth Engineering Co.Ltd.,Luoyang 471013,China;School of Civil Engineering,Henan University of Science and Technology,Luoyang 471000,China)
出处
《科学技术与工程》
北大核心
2022年第27期12131-12138,共8页
Science Technology and Engineering
基金
国家自然科学基金(U1604135)
中交第二公路工程局有限公司重点科技研发项目(2020-5-19)
河南省科技厅产学研合作项目(2015HNCXY011)。
关键词
软弱地层
大直径钢顶管
椭圆化变形
屈曲模态
稳定性系数
soft stratum
large diameter steel pipe jacking
elliptical deformation
buckling mode
stability coefficient
