合福客运专线滑坡发育区工程地质选线

高速铁路工程其曲线半径大,对线形要求严格,而滑坡对高速铁路工程的施工、运营影响极大。如何在滑坡发育区进行工程地质选线以快速稳定山区高速铁路线位方案,既确保线形平顺,又确保滑坡段的铁路安全、经济就显得尤为重要。结合合肥至福州铁路客运专线南雅至福州段可行性研究阶段的工作,采用遥感选线、踏勘及测绘选线、勘探选线及大范围地灾评估四个步骤进行了滑坡发育区高速铁路工程地质选线。通过该四步工作方法,及时稳定了线路方案,为进一步开展工作提供了重要保障。避开所有滑坡而不考虑铁路线形,或者一味地追求线形而不考虑滑坡影响都是片面的,对大型、处理后隐患大的滑坡宜绕避,但对于规模适度、适宜处理的滑坡选择合适部位通过,对高速铁路工程选线而言是大有裨益的。     

An Approximate Analytical Solution for Grout Transport Modeling： A Case Study in Luling Mining, China

This case study describes the effects of a grouting process developed to decrease groundwater flow exiting from a ruptured mine ventilation shaft lining in Luling coal mine at Huaibei, China. The primary purpose of grouting at this site is to prevent groundwater flow into the mine from adjacent aquifers. The study supports a transport perspective to describe the miscible grout movement, and provides an approximate analytical method to determine grout concentration based on Wilson and Miller's (1978) model. This study shows that the breakthrough curves (BTCs) established from the Wilson and Miller's model match the experimental BTCs obtained from test grouting performed at the site, and Rd a retardation factor of 1.1 is determined. The retardation factor and the BTC are subsequently used to guide the actual production grouting. The monitored result shows that the groundwater inflow at the disrupted ventilation well has been reduced by 47% after drilling and grouting just one borehole. The discharge rate was measured at no more than 4 m3/h after completion of four injection boreholes, which is about 13% of the 30 m3/h before grouting.     

气候变暖对青藏铁路多年冻土区路基影响分析

通过对青藏高原气候变化预测情况的认识,采用数值模拟计算,对两种不同升温条件下多年冻土区的热状况及对年冻土退化范围进行了预测,并据此提出了气候变化背景下多年冻土区路基工程的总体设计原则.对升温条件下多年冻土区路基工程的稳定性进行了分析,总结了气候变化对青藏铁路多年冻土区路基工程的影响.     

Study on DSM-based task planning of product cooperative development

The results of analyzing the managerial characteristics and complexity of product cooperative development suggest that task planning is an important aspect for process management of product cooperative development and the method for planning tasks should be able to model the dependency between tasks and iterations during the development process. In this paper, a DSM-based method and its corresponding optimization algorithms are developed. At first the coupled task sets and uncoupled task sets are identified, and the tasks are then optimized by the corresponding algorithms. The optimal tasks plan will reduce the development time and cost. Considering the practical requirements in real world, a Multilayer DSM is proposed, and its information communication techniques between DSM and traversing principle are described in details.     

Analysis of motion in longitudinal plane of negative buoyancy vehicle flying fish II

This article describes an experimental prototype flying fish II and builds a dynamic model that is a novel type of autonomous underwater vehicle (AUV) under the condition of negative buoyancy vehicle (NBV) without large buoyancy mechanism. Compared with the AUV Remus100, the flying fish II can cruise with double speeds within the same range and dimensions. The static stability and motion modes of flying fish II in the longitudinal plane are analyzed through the linear system theory. The flying fish II has static stability in the longitudinal plane and the motion mode is related to metacentric height.     

智能铁路内涵与特征的探讨

面对铁路运输需求的不断增长,高速、重载运输的快速发展,增强运输安全保障能力、提升运输服务质量、提高运输能力等需要,铁路需要智能化发展.本文论述了发展智能铁路的重要意义,分析了国外铁路智能化研究与发展情况,定义了智能铁路的概念,阐述了智能铁路的涵义和核心特征,并探讨了智能铁路发展的内容.     

北京市公交车典型行驶工况的构建

选取北京市36条典型公交车行驶路线,用GPS进行了连续一周的车速采集,累计行程6000多公里,获取了100多万条行驶速度数据。运用聚类分析方法对样本数据进行初步分析,确定了所需的数据样本;再用MATLAB软件进行编程计算,对样本数据进行了整理和分析,最后构建了公交车辆道路行驶工况。对比分析表明它与欧洲地区的行驶工况存在一定的相关性。     

多年冻土区热棒路基应用效果

为了研究热棒在青藏公路多年冻土区的应用效果,基于楚玛尔河试验监测场地8年的地温观测数据,以水平温度梯度为指标,分析了不同时期热棒的有效半径。为了提高热棒的调控效果,拓展热棒的使用范围,满足宽幅路基强吸热的使用要求,依托北麓河与安多2个试验监测场地,分析了热棒-XPS板路基与热棒-片块石路基地温监测数据。分析结果表明:热棒工作1年后的有效半径约为2.3m,此后,随着热棒工作时间的增加,热棒影响范围逐渐增大;在热棒工作的前5年,地温降幅明显,周围土体地温降幅都基本维持在0.5℃以上,之后每年降温较小,这主要是由于外界环境温度升高,气温与地温的温差逐渐减小,热棒工作的动力逐渐衰减引起的;在热棒工作的8年中,由于热棒的持续制冷作用,热棒路基的人为上限基本不变,而普通路基同时期人为上限最大降低约为80cm;热棒-XPS板路基从6月份开始,XPS板上下温差不断增大,最大温差约为17℃,有效阻隔了暖季大量热量向板下传递;热棒-片块石路基通过2年的调控作用,地温最大降幅为0.51℃。     

基于“离岛交通”模式的生态旅游景区交通发展策略研究

为缓解生态旅游景区高峰期交通供需严重失衡、交通拥堵严重等问题,文章提出了"离岛交通"发展模式及其内涵,从岛外交通快速抵离、岛内交通低碳慢行、内外交通无缝衔接、设施配置逐层减弱、多元化品质交通服务等方面,提出了大鹏半岛发展"离岛交通"模式的具体策略,以构建一体化、可持续、多元低碳的旅游交通体系。     

大跨度混凝土连续箱梁桥零号块局部分析

为了探究大跨度混凝土连续箱梁桥零号块位置处的应力扰动问题, 利用三维实体有限元方法, 对某预应力混凝土连续箱梁桥的零号块进行了精细的空间有限元分析, 总结了大跨度混凝土连续箱梁桥零号块的应力分布特征及其建模方法。