Application Strategies of Pipe Jacking Technology in Municipal Rainwater Pipeline Engineering

Traditional construction techniques have a significant impact on the environment and are associated with long construction durations in the construction of municipal rainwater pipelines.Pipe jacking technology,a new type of pipeline construction method,enables non-excavation construction and can address the shortcomings of traditional pipeline construction.This article analyzes the concept and application advantages of pipe jacking technology.Combining engineering examples,it explores the application strategies of pipe jacking technology in the construction process of municipal rainwater pipelines for reference.

基于JACK虚拟仿真的学龄前脑瘫儿童助行器人机优化设计

目的减少学龄前脑瘫儿童助行器的安全隐患,解决患儿在训练过程中的肢体二次损伤问题,提升助行器人机舒适性,对学龄前脑瘫儿童助行器进行优化设计。方法通过JACK虚拟仿真软件的RULA工具,分析得到学龄前脑瘫儿童在使用助行器过程中存在的不合理姿势,并对其进行人机工学与受力分析,提出改进方法并进行设计优化,最后导入JACK虚拟仿真软件进行风险与舒适性验证。结果优化后的学龄前脑瘫儿童助行器的使用受伤风险从4级降低到1级,患儿躯干弯曲力矩、L4/L5脊柱压缩力、剪切力的姿势载荷指数分别降低53%、47%、81%,上身各关节处于舒适角度。结论经过JACK仿真分析及人机优化后的助行器,有效降低了学龄前脑瘫儿童在康复训练中的二次损伤风险,减轻了患儿步行训练中的身体负担,提升了助行器使用的舒适性。

A study of jacking force for a curved pipejacking

For a pipejacking, the jacking force is critical to balance the resistance force and to move the pipe string forwards. The driving mechanism of a curved pipejacking is more complicated than a straight-line pipejacking, and its jacking force is also more difficult to be determined. The paper theoretically studies the jacking force of a curved pipejacking by considering the static equilibrium of earth pressure, resistance at cutting face, friction at pipe surface, and the driving force behind the pipe string. The derived theoretical formula can be used to estimate the driving forces of a straight-line or a curved pipejacking. Case study was performed by applying the theoretical and empirical formulae. After calibration, the corrected formula is more accurate and more applicable.

Application of ANSYS 3D FEM in Studies of Surface Deformation Caused by Pipe Jacking

By using site observation data and establishing 3D model using ANSYS software, this paper has discussed the strain change of stratum stress during process of jacking-in and the impact of machine head on ground surface under different frontal resistances. Analysis of the two cases shows that soil pressure reaches its maximum point when the soil is right above machine head, and soil stress will gradually decline when machine head passes over it. It also shows that impact brought by pipe-jacking construction on stress change of the surrounding soil is limited. The thesis suggest that road surface should be consolidated and soil condition be improved before construction to prevent loss and disaster caused by road surface deformation, jacking force can be increased so that jacking efficiency can be enhanced when ground stratum is well filled with soil, but the frontal resistance facing machine head should be equal to surrounding soil pressure in order to avoid rise of ground surface.

Behavior of Surrounding Soil during Construction and Its Countermeasures Using Pipe Jacking Method in Deep Strata

In Japan when urban infrastructures need to be constructed, the difficulty of utilizing the ground or shallow strata will lead to a more frequent use of the deep strata. The common construction methods are open-cut, pipe jacking, and shield methods. In recent years, a new pipe jacking method has been established that can be adapted to 20 m below the ground or more. Using this method, the drivage machine and the jacking pipe continue to move an underground until the completion of the driving. Therefore an over-cutting area (so-called tail-void) must be formed to lower the friction between the ground and the pipe. The tail-void is filled with lubrications. However, because the stress release from the ground continues to advance when the tail-void is formed, hence there are some challenges required to cope with the stability of the surrounding ground. In order to utilize the pipe jacking method in the deeper strata layers, the theory, analysis and installation of tail-void have to be systemized, and such systematic data must be stored. Therefore, the conditions of tail-void in the deep pipe jacking method are discussed using numerical analyses.

Effect of Application of Pipe Roof Method by Using Pipe Jacking on Behavior of Surrounding Soil

Tunnels in an urban area, in many cases, are constructed in soft ground which contains underground water, near existing facilities and structures. Structural stability for the tunnel and also the nearby structures and facilities is vital in this kind of work. Slurry pipe jacking was firmly established as a special method for the non-disruptive construction of underground pipelines of sewage systems. This method utilizes mud slurry that is formed around the pipes in order to stabilize the surrounding soil. In the pipe roof method the tubing elements that are constructed by slurry pipe jacking are near each other longitudinally, and create a rigid and stable lining before the excavation of the main tunnel. This paper discusses ＇the application of a slurry pipe jacking system on ＇the pipe roof method by means of numerical analysis. Because of the rigid behavior of the lining, the results show little subsidence, making this method a reliable method of constructing large tunnels with small cover in an urban area.

基于Jack的挖掘装载机驾驶室人机工程分析与改进设计

为提高挖掘装载机驾驶室的舒适性,采用人体模型建模分析法确定H点位置,并建立挖掘装载机驾驶室人机仿真系统。以人机分析软件Jack为工具,从驾驶员可视性、可达性及舒适性3方面进行挖掘装载机多作业姿势的人机合理性分析,根据仿真结果对中控台界面及控制部件布局进行改进设计,改进方案的分析校核结果表明:驾驶员可视域得到提升,常用控制部件位于驾驶员舒适可达范围内,改进后驾驶员的多个作业姿势舒适性得到提升。通过人机仿真软件对驾驶员多作业姿势进行人机合理性分析,较准确地发现了挖掘装载机驾驶室存在的设计缺陷,为具有复杂人机系统的工程装备驾驶室布局设计研究提供一定参考。

基于Jack的老年电动代步车人机工程设计与优化

目的满足行动不便的老年用户群体复杂的出行需求,提高电动代步车类工具使用过程中的舒适度。方法在传统老年电动代步车的基础上附加辅助站立结构,创新设计出一款坐、立两用的新型电动代步车,并借助Jack仿真软件,对老年用户坐姿驾驶和辅助站立支撑状态下的舒适度、可达域、可视域,以及上车过程中L4/L5下背部的受力情况进行分析,以验证关键人机交互结构、尺寸设计的合理性及舒适性。结论通过验证和调整,对电动代步车的初期设计方案进行改进,优化后的方案为老年电动代步工具的设计提供了参考,可以为满足老年用户复杂的出行需求、提高电动代步车类工具使用过程中的舒适度和安全性提供帮助。

基于JACK的不同身高笔记本电脑使用者的脊椎受力状态研究

目的在探讨笔记本电脑放置位置对使用者胸椎、腰椎受力和头部屈曲的影响。方法通过Jack软件构建了P 1、P 5、P 50、P 95和P 99的数字人仿真办公模型,分析了屏幕在不同垂直距离和水平距离下人体spinetT1/T2、spineL4/L5受到的力矩和Head Flexion的角度,使用SPSS对获得的数据进行相关性分析。结果在坐姿使用笔记本电脑时,用户的身高越高,其胸椎和腰椎所承受的力矩也越大。笔记本电脑屏幕的高度对使用者的影响显著高于水平距离的影响。结论通过调整笔记本电脑的放置位置,特别是屏幕的高度,可以有效降低不同身高群体颈部和腰部的疲劳和疼痛症状,减少对身体的损伤。

Long-Distance Pipe Jacking in Complex Urban Geological Environment

A steel underground pipeline with a diameter of 2.4 m and a total length of 3,617 m(plate thickness of 26 mm)has been constructed in a city in central Hubei,and the engineering,procurement,and construction(EPC)project has been lifted from the upstream channel to supplement water to the downstream lake inside the city.Through preliminary geological survey data,site topographic and geomorphic survey,urban construction,as well as the requirements of the construction party,the preliminary arrangement of working wells and receiving wells as well as the selection and customization of pipe jacking machines have been proposed.Frequency conversion motor and remote monitoring technology are adopted for geotechnical change and long-distance pipe jacking.Through detailed survey,the rock and soil change section as well as gradual change conditions have been determined,the accuracy of construction mechanics calculation and construction operation control have improved,the basis and analysis basis are provided,and some experiences in construction operation are summarized.

Numerical simulation of frost jacking response of a single pile considering hydro-thermo-mechanical coupling

Permafrost is widely distributed in China and around the world.In permafrost regions,soil frost heave and thawing are severe and frequent,and can destabilize pile foundations.To this end,a finite element model of a single pile in frozen soil is established to investigate the frost heave and frost jacking response to ensure its safety in the Qinghai-Tibet Plateau.Firstly,a hydro-thermal coupling model of a single pile in frozen soil is established based on coupling parameters and initial and boundary conditions.Then the temperature and moisture distributions are analyzed through the established coupling model.A hydro-thermo-mechanical coupling model is developed by importing the ice content and temperature results.Simulation results indicate that the amount of frost heave is greater at locations closer to the ground surface,and the displacement is smaller for frozen soil that is closer to the side of the pile.The results on frost jacking behavior of piles from this study can serve as a reference for the design,construction and maintenance of foundations.

Finite Element Analysis Study of Box Culvert Jacking-Out Construction under Existing Railway Line

To shorten the existing box culvert demolition construction period and ensure the normal operation of the railway, the jacking-out construction method was adopted. The ABAQUS finite element software was used to establish a three-dimensional model of the box culvert and soil body of the relying project, and three excavation thickness (0m, 1 m, 2 m) were used as the main variation parameters for numerical analysis and research, and the change law of the box culvert itself and soil body stress during the culvert jacking out process was obtained. The results show that the jacking force-displacement curves of the three working conditions can be divided into two stages, and the jacking force reaches the maximum value at the moment when the static friction turns into sliding friction at the end of the first stage. The stress distribution at the bottom slab of the box culvert in the jacking process is approximately normal, and the stress decreases with the increase of the roadbed excavation thickness. The increase of the roadbed excavation thickness can reduce the soil pressure on the side of the box culvert and effectively reduce the deformation of the roadbed in the jacking-out process. The deformation of the roadbed during the jacking process can be reduced by increasing the thickness of the roadbed excavation.

基于人因学及Jack仿真的消防操作台设计

从人因学的角度出发,根据消防救援任务对车载单人消防机器人操作控制平台进行设计,并依托计算机辅助布局方法和双手作业分析,借助yaahp软件等进行操控器位置协助和布局,针对设计后的人机界面进行了Jack仿真分析,通过人因学多项反应时间实验及按键双手协调实验对设计效果进行分析评价,以减少长期作业带来的疲劳,有效提高作业人员操作的精准性。

Discussion on the Application of Pipe Jacking Construction Technology in Municipal Road Drainage Projects

In the construction of municipal road drainage projects,pipe jacking construction is a relatively common construction method.This construction technology can avoid a large amount of excavation work,improve drainage construction efficiency,avoid large-scale damage to the road surface,and exert small traffic impact.Therefore,it is currently widely used in drainage construction,but judging from the current actual application situation,there are still many problems that require further improvement.This article mainly analyzes the advantages of and current technical problems in pipe jacking construction technology in detail,explores corresponding solutions,and lays a foundation for the optimization of municipal road drainage engineering construction.

基于JACK软件的人工检验台人因工效评价

为了提升成品检验台作业人员工作的舒适性,以J公司光伏新能源生产线的成品检验台为研究对象,基于工效学理论,运用Jack软件,构建数字人模型,对成品检验操作台进行建模仿真。对于数字人的工作环境进行了舒适度和疲劳度的检验,发现了其中存在的问题,同时提出了相应的改善措施。数据显示,通过调整工作台布局等方式,数字人的工作舒适度得到显著提升。

基于JACK平台的作战仿真研究

针对目前作战仿真Agent无法适应复杂战场环境、动态规划能力不足的问题,找到了一个基于BDI行为模型的多Agent智能开发平台JACK。基于此平台,开发了装甲步兵班阵地进攻作战仿真系统;依托JACK Team平台,设计了作战仿真Agent能力组件的结构、功能类和行为算法,构建了单兵行为模型和班组行为模型;通过表现模块,实现了JACK Team和Unity3D仿真环境数据交互。同过系统仿真数据统计,验证了JACK平台BDI模型的有效性和与开放环境的良好交互性。

基于Jack仿真的助浴产品作业过程人机优化设计

为解决助浴师在长期上门助浴作业时可能导致的肌肉骨骼疾病问题,本文对助浴产品作业过程进行人机分析和设计优化。首先基于HTA法对助浴行为进行分层归纳,再利用Jack软件模拟助浴环境,对助浴任务进行分析,最后基于分析结果进行人机优化设计实践。本文提出可供参考的助浴床尺寸设计标准,为助浴床增加辅助翻身结构。有助于减少助浴师的疾病风险及提高工作效率,为助浴产品行业提供人机设计标准,促进行业的发展和创新。

JACK虚拟技术在列车卧铺爬梯设计中的应用研究

卧铺爬梯对乘客的安全和舒适至关重要。对国内外列车卧铺爬梯设计现状分析基础上,以人机工程仿真软件JACK为工具,建立了面向对象的虚拟乘客模型及上下爬梯、从爬梯到卧铺的连贯动态行为仿真模型,在此基础上,测试了乘客上肢可达性、动态行为的关节舒适性和视觉可视性,进行了相应的工效评价,辨识出爬梯设计中的人机缺陷,提出了相应的改善建议,并进行了优化设计,为完善爬梯设计提供了一定的参考。

基于JACK的驾驶舱仿真及人机工效分析

在驾驶舱的设计中应用人机工效学原理,利用JACK软件对舱内布局设计进行仿真及舒适性、可达域、可视域等工效进行评价,并提出修改意见。首先将基于人机工效学设计的驾驶舱的CATIA模型导入JACK软件中创建分析对象;然后基于JACK软件建立用于仿真工效分析的数字人模型(Digital Human Model),将数字人模型调整成驾驶员工作时的最优姿势,仿真驾驶员位于驾驶舱的虚拟环境。最后应用JACK软件的人机工效分析工具对驾驶舱内部进行分析并提出改进意见,这样既缩短了设计周期,又减少了设计制造费用。

基于JACK的某自行高炮乘员舱人机工效评估

运用JACK软件的工效评估功能,创建了P5、P50、P95我国成年男性人体模型,将某自行高炮乘员舱UG优化模型导入到JACK中,对舱内乘员座椅、操控台、方向机、高低机、车长镜和行军固定器进行了工效评估。通过评估,指出了原设计中的一些不合理之处,提出了改进措施,解决了自行高炮乘员舱缺乏可靠的人机工效评估的问题。