杭州地铁1号线盾构掘进对周围土体扰动分析

文章以杭州地铁1号线红普路站—九堡站区间段右线隧道盾构掘进为工程背景,对盾构掘进过程中周围土体的变化情况进行了试验性监测研究,其监测内容包含地表沉降、分层沉降、水平位移和孔隙水压力。通过监测数据分析表明:地表沉降主要集中在盾构通过前接近监测断面和盾尾离开监测断面这一期间;在盾构通过时,隧道盾构外侧土体存在明显沉降,而在盾构通过前、后,土体均有不同程度的隆起,并且横向水平位移较大,受挤压效果明显;盾构切口到达和盾尾离开时,孔隙水压力都会出现突然增大随后迅速减小的变化规律,反映了土体挤压、恢复和松弛等扰动状态。     

Heuristic search for the coupled runway sequencing and taxiway routing problem

This paper presents the first local search heuristic for the coupled runway sequencing (arrival & departure) and taxiway routing problems, based on the receding horizon (RH) scheme that takes into account the dynamic nature of the problem. As test case, we use Manchester Airport, the third busiest airport in the UK. From the ground movement perspective, the airport layout requires that departing aircraft taxi across the arrivals runway. This makes it impossible to separate arrival from departure sequencing in practice. Operationally, interactions between aircraft on the taxiways could prevent aircraft from taking off from, or landing on, runways during the slots assigned to them by an algorithm optimizing runway use alone. We thus consider the interactions between arrival and departure aircraft on the airport surface. Compared to sequentially optimized solutions, the results obtained with our approach indicate a significant decrease in the taxiway routing delay, with generally no loss in performance in terms of the sequencing delay for a regular day of operations. Another benefit of such a simultaneous optimization approach is the possibility of holding aircraft at the stands for longer, without the engines running. This significantly reduces the fuel burn, as well as bottlenecks and traffic congestion during peak hours that are often the cause of flight delays due to the limited amount of airport surface space available. Given that the maximum computing time per horizon is around 95 s, real-time operation might be practical with increased computing power.     

Prediction of ground vibration amplitudes due to urban railway traffic using quantitative and qualitative field data

The growth of railway transport in urban areas has lead to an increase in ground vibrations enhancing their negative environmental impact. Therefore is mandatory to predict and control ground vibrations. This work presents a methodology for the determination of prediction models of ground vibration amplitudes due to railway train circulation in urban environments. Using quantitative predictors (train speed and distance) and qualitative predictors (railway track type, dominant geology and building type), being the use of the latter predictors justified by the fact that, most frequently, quantitative parameters are very difficult to obtain in the urban environment due to their characterization. Thus, a detailed statistical study based on the proposal and validation of multiple linear regression models, is successfully applied in order to predict vibration amplitudes produced by railway train circulation, in the considered domain, as function of quantitative and qualitative predictors, easily obtained in field work. A multiple linear regression model for ground vibration prediction due to underground railway traffic has been presented for the Lisbon area.     

复杂条件下地铁车站施工关键技术

在复杂条件下为使地铁车站项目的施工质量、工期、造价和安全目标得以实现,关键施工技术的正确采用至关重要。文章以沈阳中街地铁站为例,针对工程施工所面临的复杂条件,对施工技术路线的确定和施工方案涉及的关键技术进行了分析和探讨。工程实践及良好的施工效果表明,项目施工中采取的注浆加固、大跨度扣拱、超前地质预报以及施工防水等关键技术,对近接建筑物、不稳定地层下开挖大跨度隧道施工中有效控制地表沉降、保护周边建筑物及管线安全起到了关键作用。     

砂砾地层电力顶管施工引起的地面变形研究

文章针对砂砾地层电力顶管施工引起的地面变形开展研究。首先,基于现有散粒土的沉降理论计算公式,进行某砂砾地层电力隧道顶管施工引起地面变形的理论计算和分析;其次,通过理论分析和现场实测,得到砂砾地层顶管施工引起的地面变形规律;最后,在现有理论计算公式和监测数据的基础上,利用规划求解,提出适用于砂砾地层顶管施工引起地面变形的沉降槽宽度系数计算公式。研究结果表明,土体损失是引起地面沉降的主要影响因素,沉降计算时必须考虑土体损失在顶进过程中的动态变化;修正沉降槽宽度系数计算公式能够较好地适用于砂砾地层中顶管施工引起的地面沉降计算。     

冻结法施工地铁旁通道引起的隧道及地表沉降规律研究

从时间和空间上对冻结法施工地铁旁通道引起的周围区域隧道及地表沉降进行分析研究,获得了隧道及地表沉降规律.根据获取的沉降规律,针对冻结法施工地铁旁通道提出了减小隧道及地表沉降的有效措施.     

复杂条件下城市地铁隧道施工地表沉降研究

针对深圳地铁大剧院—科学馆区间工程具有地层软弱富水的复杂工程地质条件、暗挖隧道结构呈洞群系统的复杂工程施工条件、近邻建筑物和管线密布的复杂工程边界条件等特点，综合运用理论分析、现场测试、离心试验、数值模拟等多种研究手段，对施工过程中的施工安全进行预测并提出相应的控制策略。主要研究内容及结论如下。     

计算机联锁系统防雷措施研究

随着微电子技术在铁路信号设备中的广泛应用,雷电防护成为计算机联锁系统中必不可少的一部分.就计算机联锁系统防雷的研究与应用进行了探讨.     

高速列车作用下板式轨道引起的地面振动

根据波数域内分层大地波动方程的求解理论,建立高速列车作用下板式轨道—大地耦合振动分析模型。利用Fourier变换,在频率—波数域内求解振动微分方程,再通过Fourier逆变换得到大地表面的振动位移响应。通过算例分析列车运行速度对板式轨道周围地面振动的影响。结果表明:列车运行速度越高,线路周围地面的振动响应越大。当列车速度大于200 km.h-1时,路基表面位移的幅值随车速提高迅速增大;然而当列车速度增至350 km.h-1时,位移幅值最大值又出现了回落。距离板式轨道中心线越近,行车速度的变化对地面振幅的影响越显著。尤其当列车速度接近地基的Rayleigh波波速时,由于引发共振而使地面振动位移出现峰值。     

三管盾构隧道下穿铁路引起的地表位移及其控制技术

采用三维数值模拟方法,结合上海轨道交通9号线R413标段,进行三管并行盾构隧道近接下穿南新环铁路引起的地表位移及其控制技术研究。数值分析中,利用温度升降产生的膨胀和收缩效应模拟注浆压力和压力的消散,使得分析过程在力学效应上更接近盾构施工的工作状态。引入轨道高低偏差值来控制地表位移。研究结果表明:地层加固前,各隧道施工时地表的横向位移有明显的叠加效应,距离越近,效应越明显,且最大位移值已超过限值;当采用分块注浆加固地基并配合旋喷桩施工的地层位移控制技术后,地表位移得到有效的控制,现场沉降实测结果验证了控制技术的有效性,确保盾构隧道安全下穿铁路和列车的安全运营。