虚拟现实技术在隧道开挖工程中的应用

针对复杂地质结构与多地质灾害风险的地下隧道开挖安全和科学施工,提出了一种隧道开挖计算机仿真方法。方法首先以地质勘探资料为基础,通过智能推演和人机交互方法进行三维地质建模,然后应用计算机仿真技术虚拟隧道开挖,最终揭示隧道围岩地质结构变化特征,实现隧道开挖过程中的地质灾害风险预警。方法成功地应用于几个大型铁路隧道开挖工程,结果证明该方法能够有效预测隧道围岩地质结构变化与地质灾害可能发生的空间位置、类型与级别。方法为实际隧道科学施工决策、安全开挖提供了可靠依据。     

高速公路隧道电缆桥架标准化施工探讨

<正>高速公路隧道机电设备安装工程是高速公路机电安装工程中的重点和难点。特别是其中隧道照明工程不仅要求电缆桥架和照明灯具高度满足设计文件、技术规范要求不侵入隧道建筑界限,安装牢固可靠,而且要求视觉、外观效果良好,其电缆桥架的安装要做到隧道直线段横平竖直,线性良好,曲线段平滑对称。本文就高速公路隧道内电缆桥架的标准化施工进行了探讨。1隧道电缆桥架安装工序隧道电缆桥架安装工序为:施工准备→电缆桥架支架安装定位     

冻融条件下隧道防水注浆施工技术分析

在冻融条件下,在隧道倾斜等因素的影响下,沉积岩和结构化合物中的渗流很难观察到,隧道的安全无法保证。水密气化是防止隧道渗漏的措施之一,有助于提高隧道施工质量。在隧道施工中,结合大量文献,分析了隧道施工在霜露条件下的防水机理。同时,结合具体工程,对隧道防水施工进行了研究。     

基于贝叶斯网络的隧道围岩失稳风险预警方法

为了对隧道围岩失稳风险做出准确判断,预防围岩失稳灾害的发生,将贝叶斯网络方法应用于隧道围岩失稳的风险预警。在系统分析隧道支护参数影响围岩稳定性的基础上,通过引入基于贝叶斯网的知识表达和相应的不确定性推理原理,构造了隧道围岩失稳风险预警专家系统;并通过工程案例验证了隧道围岩失稳风险预警专家系统好的适用性。贝叶斯网专家系统可以充分利用专家的先验知识和已有案例提供的或概率分布,可以使推理在输入数据不完备的基础上进行,能够有效地实现围岩失稳风险预警。     

下穿高压输电塔大跨度隧道结构监测中传感器的应用

为了保证上覆高压输电塔的安全正常运行,必须要掌握下穿隧道施工对地层的扰动和支护结构的受力情况。结合李家冲隧道下穿500kV高压输电塔实体工程的现场监控量测,介绍了相关监测方案及其监测结果。结果显示：隧道施工过程中,围岩变形趋于稳定,钢拱架和二衬内力的安全系数均满足设计规范要求,说明隧道施工方案合理,工程结构稳定可靠,所用传感器有效完成相关监测任务。     

隧道凿岩台车发展史上的一个里程碑--《隧道凿岩机器人》图书问世

隧道施工中潮湿、粉尘多、振动大、噪声高，隧道施工是一项污染严重、劳动强度大的工作，隧道凿岩台车是钻爆法隧道施工中必备的大型工程装备。为促进工程机械的智能化，降低劳动强度、减少隧道施工对施工人员的危害、提高工程质量、提高施工效率与经济性，以中南大学何清华教授为首的团队成功开发了国内第一台隧道凿岩机器人，     

权重自适应模糊层次分析方法及应用

借鉴了误差反向修正理论和增量式的思想,结合层次分析法固有的优势,提出了具有自适应能力的权重设定层次分析法(adaptive weight setting method,AWS)新方法,使盾构法隧道施工风险识别模型能够利用较少的施工数据,完成进行权重调整,满足了实际隧道施工中风险评估的需求.该方法在上海地铁某区间隧道工程中进行了试用,取得了良好的效果,表明了该方法的有效性和实用性.     

地铁区间隧道施工对桥基影响的空间效应分析

在桥梁下面采用浅埋暗挖进行城市地铁工程的施工,施工难度和风险极大.随着城市地铁在我国的大量修建和蓬勃发展,这些工程将会越来越多甚至不可避免,如何保证施工过程中施工和桥梁的安全,已成为近年来学术界和工程界普遍关注的现实问题.鉴于此,针对北京地铁五号线和平西桥站～北土城东路站区间隧道下穿樱花西桥这一实际工程,借助ABAQUS软件,建立了桥基-隧道围岩相互作用的三维有限元模型,模拟了隧道施工过程中地下结构和桥基的施工效应.数值分析结果表明,在拟定的施工方案下,施工期间桥基和地下结构没有安全隐患,并取得了一些有意义的结论和建议,为该工程的实施提供了依据和指导作用.     

地铁区间隧道施工对桥基影响的空间效应分析

在桥梁下面采用浅埋暗挖进行城市地铁工程的施工,施工难度和风险极大。随着城市地铁在我国的大量修建和蓬勃发展,这些工程将会越来越多甚至不可避免,如何保证施工过程中施工和桥梁的安全,已成为近年来学术界和工程界普遍关注的现实问题。鉴于此,针对北京地铁五号线和平西桥站～北土城东路站区间隧道下穿樱花西桥这一实际工程,借助ABAQUS软件,建立了桥基-隧道围岩相互作用的三维有限元模型,模拟了隧道施工过程中地下结构和桥基的施工效应。数值分析结果表明,在拟定的施工方案下,施工期间桥基和地下结构没有安全隐患,并取得了一些有意义的结论和建议,为该工程的实施提供了依据和指导作用。     

承唐高速公路双连拱隧道施工技术总结

《承唐高速公路双连拱隧道施工技术总结》以长深公路承德到承唐界段TJ12段安子岭一号隧道工程为依托,对双连拱隧道的施工技术进行了总结.该施工技术,打破常规,勇于创新,在保证安全、质量的前提下,加快了施工进度,突破了施工网络图中的瓶颈制约,并为国家节约了投资,取得了良好的社会和经济效益     

An association-based case reduction technique for case-based reasoning

Case-based reasoning (CBR) is a type of problem solving technique which uses previous cases to solve new, unseen and different problems. Although a larger number of cases in the memory can improve the coverage of the problem space, the retrieval efficiency will be downgraded if the size of the case-base grows to an unacceptable level. In CBR systems, the tradeoff between the number of cases stored in the case-base and the retrieval efficiency is a critical issue. This paper addresses the problem of case-base maintenance by developing a new technique, the association-based case reduction technique (ACRT), to reduce the size of the case-base in order to enhance the efficiency while maintaining or even improving the accuracy of the CBR. The experiments on 12 UCI datasets and an actual case from Taiwan’s hospital have shown superior generalization accuracy for CBR with ACRT (CBR-ACRT) as well as a greater solving efficiency.     

.基于遗传算法的全局优化检索策略研究*

案例检索是基于案例推理(CBR)系统中的关键技术,也是实现智能挖掘系统的关键环节。为了能够进一步提高案例检索效率与准确性,传统研究多是从案例属性和案例库的约减两方面入手,但是没有考虑案例属性权重。提出了一种基于遗传算法的全局优化案例检索模型,该模型利用遗传算法在搜索优化上的优势,对案例库、 属性权重、K-NN中的K值进行全局同步优化。最后,通过实验验证了该模型在检索效率与准确性上优于传统模型。     

Multi-agent system for tunnel-settlement monitoring: A case study in Shanghai

Special soil environment and geographic location expose tunnels in Shanghai to a higher risk of asymmetry change and non-homogeneous settlement that could make a threat to passenger safety and tunnel structure stability. Considering work efficiency and costs, current monitoring methods and frequency are not suitable for tunnel monitoring present stage requirements. To make sure tunnel under condition of economic sustainability, environmental sustainability and engineering safety, new technology and instrument for monitoring should be designed to break through. Besides, asynchrony and retardation existing in data acquisition and analysis makes monitoring task cannot reflect tunnel real-time status. This can make people unable to timely detect the occurrence and risk of tunnel disaster. The purpose of this article is to develop a tunnel settlement monitoring system with several intelligent functions for comprehensive evaluating tunnel healthy, generating seasonable warnings and guaranteeing construction sustainability. To facilitate the expansion of the system and data structure, agent techniques and condition based monitoring standard have been applied to establish the system with 9 action parts according to 3 different geospatial. Moreover, web service has also been used to provide human–computer interface and realize visual function, and meanwhile, all the procedure of the system was completed automatically. Additionally, the system was tested with a task in Shanghai tunnel, and the result shows the monitoring system can describe tunnel conditions, prevent tunnel hazards and assist managers to make appropriate decisions with less people and reduced costs.     

基于UWB的地铁隧道定位系统设计

超宽带技术因其具有定位精度高、抗多径干扰能力强、传输速率高等优势,成为了当前主流的室内定位技术。由于地铁隧道中环境恶劣,为了保证施工人员的安全,实现对地铁隧道中施工人员的实时定位,设计了基于UWB技术的地铁隧道定位系统。该系统采用对称双向双边测距(SDS-TWR,Symmetric Double-Sided Two-Way Ranging)算法以有效抑制移动标签和定位基站之间由于晶振漂移导致的测距误差,同时在基于到达时间(TOA,Time of Arrival)的定位方法上采用粒子群算法提高定位精度。实验结果表明基于UWB的地铁隧道定位系统在地铁隧道中能稳定工作且定位精度得到有效的提高,该系统具有功耗低、实现简单、定位精度高的特点,能够满足地铁隧道当中对于人员实时精确定位的需求。     

基于随机森林的隧道建成初期累计沉降量预测

隧道建设是公路建设中一类重要的工程,沉降是隧道质量监测的一项重要指标。为预防沉降带来的安全隐患,确保后期隧道正常运行,在建成初期对隧道的沉降累积量进行实时监测并对后期沉降作出较为准确的预测是很有意义的。采用随机森林模型对隧道建成初期的隧道累计沉降量进行预测,并将该模型的预测结果与深度神经网络模型做对比分析。结果表明,随...     

Polynomial Time-Marching for Nonreflecting Boundary Problems

The newly developed polynomial time-marching technique has been successfully extended to nonperiodic boundary condition cases. In this paper, a special non-periodic boundary condition, nonreflecting or absorbing boundary condition, is incorporated into the pseudospectral polynomial time-marching scheme. Thus, this accurate and stable time-dependent PDE solver can be applied to some open domain or free space problems. The balanced overall spectral accuracy is illustrated by some numerical experiments in the one-dimensional case. The error goes to zero at a rate faster than many fixed orders of the finite-difference scheme. The order of the absorbing boundary approximation is addressed in one-dimension. Also, in the two-dimensional case, a 2nd-order absorbing approximation has been incorporated into the polynomial time-marching scheme with Chebyshev collocation in space. Comparison with the previous finite-difference implementation indicates that the high stability and efficiency of the polynomial time-marching remains. The overall accuracy is mainly limited by the 2nd-order absorbing approximation.     

DRR:一种多维案例检索优化算法研究

基于本体的案例检索系统中,由于数据库中的案例数量随着时间的推移而成倍增加,案例检索的效率不断降低。提出了一种多维案例检索算法—DRR,该算法通过将多维空间案例点降维成二维空间点,利用一个二维空间点来代表类案例点组成的集合,并对此二维空间点建立R树空间索引,通过两级检索的方法,加速了检索效率和准确率。实验证明,该方法不仅提高了案例检索的准确率,还极大地提高了案例检索的效率。     

无线隧道施工监控系统瞬时故障恢复控制

隧道施工中采用无线监控技术具有减少网络布线、增加系统灵活性的优点,但是现场施工环境的复杂多变性及传感器节点软硬件不稳定性会导致监控系统瞬时故障而引发安全事故。针对瞬时故障,从保障系统功能出发,建立瞬时故障层次模型,提出了一种多层次故障恢复控制策略,对现场数据监测层、数据传输层、安全防护层、应急响应层四层瞬时故障进行处理。模拟实验表明,该恢复控制策略能提高监控系统对灾害的检测准确率和应急响应动作的执行有效率,有利于保障隧道施工人员安全。     

Developing a diagnostic system through integration of fuzzy case-based reasoning and fuzzy ant colony system

This study intends to propose a hybrid Case-Based Reasoning (CBR) system with the integration of fuzzy sets theory and Ant System-based Clustering Algorithm (ASCA) in order to enhance the accuracy and speed in case matching. The cases in the case base are fuzzified in advance, and then grouped into several clusters by their own similarity with fuzzified ASCA. When a new case occurs, the system will find the closest group for the new case. Then the new case is matched using the fuzzy matching technique only by cases in the closest group. Through these two steps, if the number of cases is very large for the case base, the searching time will be dramatically saved. In the practical application, there is a diagnostic system for vehicle maintaining and repairing, and the results show a dramatic increase in searching efficiency.