论文标题:长距离曲线顶管技术分析与研究
Analysis of Long-Distance Curve Pipe Jacking Technology
论文作者
论文导师 俞亚南,论文学位 硕士,论文专业 市政工程
论文单位 浙江大学,点击次数 105,论文页数 71页File Size2812k
2005-12-01论文网 http://www.lw23.com/lunwen_667403907/
pipe jacking; reducing friction through injecting slurry ; relay well; longdistance; curve; jacking force; stress of pipe
本文针对目前工程实践中较为普遍和先进的长距离顶管施工工艺,对管材选用,顶力计算方法选择和施工关键技术如注浆减摩、中继环设置、通风、测量等技术进行了分析探讨。 文中着重对曲线顶管的受力机理进行了分析。通过建立力学模型对曲线路线半径R、顶推力P和影响因素如管径D、管节长L、木垫片厚a、材料弹性模量E以及工具管油缸行程差(b-c)等的关系进行推导。在研究过程中分管身是或否出现拉应力二种情况,在管身出现拉应力的情况下分析了管身截面和管道接口断面二种受力状态。 研究表明,当管身出现拉应力时,曲线半径R的决定因素是油缸行程差(b-c),而顶推力P对R的影响较小;管道接口处最大压应力σmax对(b-c)值的变化敏感,(b-c)的变化对顶推力P影响不大。另一方面,当曲线半径R为定值时,P对管身的拉应力影响较大,为使管身不出现裂缝,就必须控制最大顶推力。当管身全截面受压时,允许的工具管油缸进程很小,一般小于1mm,此时曲线路线允许最小半径相当大。 文中最后通过工程实例对推导分析进行了验证。
In allusion to prevalent and advanced long-distance jacking construction technics used at present, choice of pipe material, caculate way of jacking force and some key constrction technics such as reducing friction through injecting slurry, setting of relay well, ventilation, measuring are analysed.The analysis of curve jacking force mechanism is emphasized. By setting up mechanical model, the relationship of curve radius, jacking force and effect factors such as pipe diameter, length of pipe section, thickness of wooden piece, elasticity of material and the difference of jack displacement is investigated. Two instances whether pull stress emerges on pipe section are discussed. When pull stress emerge on pipe section, two forced states of pipe section and fetch of pipe are analysed.The research indicates that when the pull stress emerges on pipe section curve radius lies on the difference of jack displacement, while it is a little influenced by jacking force. The max press stress on fetch of pipe is sensitive to the change of difference of jack displacement, and the change of difference of jack displacement has little influence on jacking force. On the other hand, when curve radius is constant, the pull stress on pipe section is greatly affected by jacking force. And at this time, in order to avoid crack, the max jacking force must be controlled. When pipe is pressed on the whole section, the allowable difference of jack displacement is small, less than one millimeter currently. And at the same time, the least allowable curve radius is quite great.In the last part of this paper, the deduction is validated by a project example.
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