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1.
AbstractWith the large-scale development and utilization of ocean resources and space, it is inevitable to encounter existing submarine facilities in pile driving areas, which necessitates a safety assessment. In this article, by referring to a wharf renovation project as a reference, the surrounding soil response and buried pipe deformation during pile driving in a near-shore submarine environment are investigated by three-dimensional (3D) numerical models that consider the pore water effect. Numerical studies are carried out in two different series: one is a case of a single pile focusing on the effect of the minimum plane distance of the pile–pipe, and the other is a case of double piles focusing on the effect of the pile spacing. 相似文献
2.
Monitoring of Over Cutting Area and Lubrication Distribution in a Large Slurry Pipe Jacking Operation 总被引:1,自引:0,他引:1
Saeid Khazaei Hideki Shimada Takashi Kawai Junichi Yotsumoto Kikuo Matsui 《Geotechnical and Geological Engineering》2006,24(3):735-755
Slurry pipe jacking was firmly established as a special method for the non-disruptive construction of the underground pipelines
of sewage systems. Pipe jacking, in its traditional form, has occasionally been used for short railways, roads, rivers, and
other projects. Basically the system involves the pushing or thrusting of concrete pipes into the ground by a number of jacks.
In slurry pipe jacking, during the pushing process, mud slurry and lubricant are injected into the face and the over cutting
area that is between the concrete pipes and the surrounding soil. Next, the slurry fills voids and the soil stabilizes due
to the created slurry cake around the pipes. Fillings also reduce the jacking force or thrust during operation. When the drivage
and pushing processes are finished, a mortar injection into the over cutting area is carried out in order to maintain permanent
stability of the surrounding soil and the over cutting area. Successful lubrication around the pipes is extremely important
in a large diameter slurry pipe jacking operation.
Control of lubrication and gaps between pipes and soil can prevent hazards such as surface settlement and increases in thrust.
Also, to find voids around the pipes after the jacking process, in order to inject mortar for permanent stabilizing, an investigation
around the pipes is necessary. To meet these aims, this paper is concerned with the utilization of known methods such as the
GPR (Ground Penetrating Radar) system and borehole camera to maintain control of the over cutting area and lubricant distribution
around the pipes during a site investigation. From this point of view, experiments were carried out during a tunnel construction
using one of the largest cases of slurry pipe jacking in Fujisawa city, Japan. The advantages and disadvantages of each system
were clarified during the tests. 相似文献
3.
为了保障顺利建设上海市地下管线数据库.需要对现存的地下管线的源数据进行一些技术处理,以满足数据入库的要求。本文主要个绍:笔者在从事地下管线源数据处理工作中,碰到的现存的上海市地下管线源数据对于建设上海市地下管线数据库所存在的一些问题:以及笔者利用Autodesk公司的AutoCAD二次开发工具开发的应用程序来处理这些问题的方法。 相似文献
4.
本文论述了利用城市地下管线信息系统对武汉地铁和长江隧道沿线进行地下管线现状调查的过程和方法,结果表明利用该系统所完成的分析和成果资料满足了武汉及长江隧道沿线工程可行性研究的需要。 相似文献
5.
岩体通常是以孔隙岩石为基质并包含各种成因的裂隙和溶隙的复杂多空隙组合地质材料。为研究孔隙-裂隙-溶隙多空隙组合介质的渗流特性,在简要介绍多孔介质渗流Darcy定律、平板窄缝流Poiseuille定律和圆形管道流Darcy-Weibach理论的基础上,分析了几种孔隙-裂隙-溶隙组合情况的多空隙介质渗流特性,推导出相应组合的等效渗透系数KE,给出了描述多空隙组合介质KE的一般表达式,讨论了影响各种空隙组合KE的主要因素。以普通砖模拟岩石基质,通过砖身钻孔填充及砖间缝隙填充,试验模拟了岩溶岩体和裂隙岩体中溶孔和裂隙填充后的渗透情况。试验结果与所推求理论公式计算出的KE在同一量级且误差很小,很好地验证了所推导的多空隙组合介质渗透系数表达式的有效性。 相似文献
6.
7.
考虑泥浆套不同形态的顶管管壁摩阻力计算公式 总被引:3,自引:0,他引:3
大直径、长距离顶管施工常通过注浆形成泥浆套来减小阻力,泥浆套的形态及其完整性对管壁摩阻力大小有决定性作用,现有摩阻力计算公式一般未考虑不同泥浆套形态对摩阻力的影响,计算结果与实际情况相差较大。根据不同施工状况对顶管外壁泥浆套的可能形态进行了分类及成因分析,提出了判断3种常见泥浆套形态的方法。利用半无限弹性体中柱形圆孔扩张理论探讨了注浆压力对泥浆套厚度的影响,结合非线性流体力学计算泥浆与管壁接触产生的摩阻力,最终采用挖掘面稳定假设,针对3种泥浆套形态提出了摩阻力计算公式。采用该方法对工程案例进行计算,计算结果与实测数据对比表明:现有摩阻力计算公式的计算结果过于保守,所提出的计算公式是合理和有效的。 相似文献
8.
9.
Water pipe cooling has been widely used for the temperature control and crack prevention of massive concrete structures such as high dams. Because both under‐cooling and over‐cooling may reduce the efficiency of crack prevention, or even lead to great harm to structures, we need an accurate and robust numerical tool for the prediction of cooling effect. Here, a 3D discrete FEM Iterative Algorithm is introduced, which can simulate the concrete temperature gradient near the pipes, as well as the water temperature rising along the pipes. On the basis of the heat balance between water and concrete, the whole temperature field of the problem can be computed exactly within a few iteration steps. Providing the pipe meshing tool for building the FE model, this algorithm can take account of the water pipe distribution, the variation of water flow, water temperature, and other factors, while the traditional equivalent algorithm based on semi‐theoretical solutions can only solve problems with constant water flow and water temperature. The validation and convergence are proved by comparing the simulated results and analytical solutions of two standard second‐stage cooling problems. Then, a practical concrete block with different cooling schemes is analyzed and the influences of cooling factors are investigated. In the end, detailed guidance for pipe system optimization is provided. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
10.