浅谈公路工程工地试验室的组建与管理

试验检测工作是控制工程质量的重要手段,工地试验室的规范程度直接影响检测工作的质量。从驻地环境、检测功能及布局、仪器和人员设置方面,阐述了工地试验室建设的基本内容,从资质管理、质量体系建立、授权负责人和资料管理阐述了工地试验室的基本管理内容,同时分析了工地试验室易存在的几个薄弱环节,希望为同行的试验室提供一定的参考。     

Evaluating web site service quality in public transport: Evidence from Taiwan High Speed Rail

More and more public transport system passengers plan their trips by using website services. The passengers’ perceived service quality of a website plays a crucial role in recognizing the satisfaction of a transportation service chain. This study aims to investigate the passengers’ perception of electronic service quality (e-SQ) delivery through the Taiwan High Speed Rail’s (THSR) website, by adopting the Rasch measurement model to measure a subjective latent construct: perceived e-SQ. The Rasch model can compare person parameters with item parameters, which are then subjected to a logarithmic transformation along a logit scale to clearly identify which e-SQ measurement items are appreciated by certain passengers. Analytical results show substantial differences between the perceived e-SQ of various personal characteristics such as age, income, and trip types. Empirical results also demonstrate that passengers are most satisfied with the website’s accuracy of information and introduction to the THSR stations’ surrounding area, but are not satisfied with instructions when a transaction fails as well as the carriage layout of the THSR. Our analytical results also identify which service items lead to the perceived e-SQ difference between business trip and leisure trip passengers. The relationship between the two main attribute dimensions – quality of transportation information provided and quality of website services – are also further examined. The empirical results can help a transportation system service operator to better understand how passengers perceive e-SQ and to suggest what should be improved.     

航电枢纽工程选址与布置

航电枢纽以满足航运要求为首要目标,船闸布置是影响航电枢纽选址和布置的主要因素,通过工程实例分析,总结航电枢纽选址和布置的一般要求。相对顺直河段和弯曲河段都有条件布置枢纽,但依河段具体条件的不同,布置条件有优劣。枢纽布置分为集中和分散两大类型,集中布置重点解决水电站和泄水建筑物水流对通航建筑物的影响,分散布置重点是通航汊道与主河槽相连接的上下游口门区布置。     

Edge effect of busy high traffic roads on the nest site selection of birds inside the city area: Guild response

The rapid development of road infrastructure is inevitable with increasing world human population and rise in the number of vehicles on the roads is going to be an increasing threat to native habitat of many wildlife populations around the world. The present work examines the edge effect of high traffic roads on nest site selection of birds in Udaipur city, Rajasthan (India). A total of 112 nesting site of 14 bird species (among six guilds), was recorded during the study. All six guilds (i.e., carnivore, omnivore, granivore, nectivore, frugivore and insectivore) were sharing similar kind of habitat with fine scale differences (P < 0.0001). The PCA revealed that trees with suitable GBH, canopy and height were supporting birds’ nesting diversity, but the buildings were supporting the highest number of nesting. Different guilds showed different preference to different variables. Spatial heterogeneity, less predation, optimal feeding ground and higher number of advertising and display boards of shops at roadside buildings might be crucial factors for birds’ nesting in this highly disturbed area.     

非液化场地中桩-结构体系地震响应与桩基失效模式分析

基于非液化场地-群桩基础-上部结构大型振动台试验,建立了非液化场地-桩-结构体系地震响应数值计算模型,在分析桩-结构体系动力响应基础上,深入探讨动力荷载下非液化场地中的桩基失效模式。通过对比数值计算模型所得典型地震响应结果与试验结果,验证了数值计算模型的有效性和合理性,进一步探讨了非液化地基中土-结构体系地震响应规律,重点关注在地震作用下桩基失效过程及桩基-结构体系地震破坏模式。结果表明：在地震作用下,土体加速度在松砂层中不再放大,在最上部出现一定放大,且桩基加速度反应也有相似规律;各深度处土体动剪应力-动剪应变滞回曲线表现出对角线斜率小幅减小的趋势,说明等效剪切模量也出现不同程度的降低,也即地基各处土体抗剪强度均有一定下降;桩身最大弯矩出现在桩身中下部,在桩头与土层交界面附近桩身剪力较大,说明可能发生桩头剪切破坏或桩身弯曲破坏。     

软土地区盾构下穿施工对铁路路基影响分析——以杭州地铁2号线某区间现场监测为例

盾构隧道下穿施工,将对既有铁路路基产生一系列不利的影响。当盾构引起的路基位移超过承载能力,将导致铁路轨道产生过大的弯曲及扭曲变形,从而影响列车运行的平顺性和安全性。结合杭州地铁2号线某区间隧道下穿既有铁路路基工程现场监测数据,分析在盾构下穿施工过程中列车轨道、路基坡脚及路肩的位移变化规律。实测结果发现： 1）监测点沉降变化与盾构的相对位置密切相关,可划分为盾构到达前、盾构穿越及盾构通过3个阶段; 2）盾构到达前,当盾构土压力大于静止侧向土压力将引起地表隆起,反之,则产生地表沉降; 3）盾构穿越过程中将导致地表隆起位移; 4）盾构通过后,地表沉降持续发展。由于碎石路基具有一定的调节作用,使路肩隆起值小于坡脚。铁路轨道隆起整体小于同一平面路肩,是因为具有一定抗弯刚度的轨道对土体位移有一定的抵抗能力。     

跨海桥梁桥址选择和通航净空尺度问题的探讨

桥址的合理选择和通航净空尺度的确定无论对桥梁建设还是航行安全管理来说均是十分重要的。从多年参与通航论证专题研究的体会以及国外有关文献和工程实例出发,对这两方面问题进行了探讨并提出了一些建议,为今后相关工程的研究提供参考。     

三峡工程设计中的重大技术问题

三峡工程为举世瞩目的水利工程,其工程规模之浩大、技术问题之复杂都是罕见的。该文选择了工程设计中坝址的选定及枢纽建筑物设计中的若干关键技术问题进行介绍和阐述,以期读者对三峡工程有更深入的了解。     

基于设计模式的内容管理系统"多站点发布"设计

设计模式对当代的面向对象程序设计技术做出了巨大的贡献，为开发人员带来了福音。通过设计模式，程序的结构比以往更为有效。在内容管理系统“多站点发布”的设计中通过引入设计模式并对模式进行组合和简单实现不仅提高了系统设计的可重用性也避免了过分的设计，最终达到了设计与解决问题之间的最佳平衡。     

沥青路面现场冷再生技术的应用研究

沥青路面现场冷再生技术在国外的研究与应用已有较长的历史,作为一项在旧路改、扩建工程中的新技术已相当成熟并被普遍采用。而在我国该技术只处在摸索阶段,尚未形成完整的设计方法、施工工艺及相应的质量控制标准。为使该技术在工程中得到推广应用,对沥青路面现场冷再生技术的设计、施工工艺、质量控制进行了初步研究。根据大量试验结果和试验路铺筑过程,推荐了冷再生基层的级配范围和适合于冷再生材料的施工工艺。