盾构隧道机车脱轨恢复技术研究

济南轨道交通R3线某标段隧道施工中,针对隧道机车水平运输故障率和脱轨率较高的弊病,设计了一种可在隧道内搬运机车的隧道叉车,其举升和横向移动均可由液压油缸精确控制,解决了隧道机车脱轨恢复问题,使脱轨车辆快速、安全地平稳复位、降低了劳动强度,提升了施工效率.     

基于虚拟仿真技术的风景园林设计课程教学改革与实践

风景园林设计课程是风景园林专业的主干课程,对提高专业学生的规划设计能力有着重要作用.伴随信息时代的快速发展,传统教学模式已经难以满足社会需求.文章立足虚拟仿真的实践教学,从教学模式、虚拟仿真技术的运用及创新意义三个方面提出教学改革,有针对性地对课程进行了改革探索,希望通过对该课程进行教学改革而提高教学质量,以期更好地为风景园林专业服务.     

关于项目代建方工作职责的思考

根据代建制的内涵,在代建实践工作中的认识,分析了建设项目前期、设计、施工各阶段的主要工作职责,即设计方案及图纸优化,创造和谐的工作氛围,做好参建各方之间的协调工作,加强合同管理,监督各方切实履行各自职责,严格控制工程质量、投资、进度,竣工验收后移交使用方。     

CFG桩—碎石桩组合型复合地基的应用实例及问题分析

介绍了CFG桩—碎石桩组合型复合地基在某工程中的应用,总结了该项技术在工程实践中需要注意的一些问题。     

Post-yield response of cold-cambered wide flange steel beams

The post-yield response of steel beams is important in steel fabrication particularly for setting cambers. A commonly used cambering process known as “cold cambering” consists of bending the girder about its strong axis using single or dual symmetrically applied concentrated loads. This paper recasts available solutions for wide flange steel beams relating loads to permanent deformation in parametric form to determine the effect of cross-sectional geometry and load position on its post-yield response. Sensitivity analyses were then conducted to identify appropriate values of these key parameters and their impact on alternative cambering set-ups. This allows optimization of the cold cambering operation for single- and dual-load systems. The analysis shows that dual-load systems offer significant benefits over single-load systems as they develop the required camber profile at smaller loads without overstraining the steel section. The best results are obtained if the spacing between the two loads is kept within one-third to one-quarter of the span.     

边缘之见

该文从建筑文化的角度对建筑的边缘、生活场的边缘及城市的边缘等部分做了一系列的摸索,提出应珍视边缘的规划与设计,此中可以创造出有个性的文化来.     

软土地层盾构机施工管片上浮原因及控制措施

北京市轨道交通17号线某盾构区间施工过程中发生管片上浮问题,最大上浮量达114mm.经分析原因是水文地质条件不利、同步注浆造成管片受力不均、施工参数设置不合理等,针对上述原因提出软土地质条件下控制盾构隧道管片上浮的技术措施,取得了较好效果.     

基坑支护中土压力系数计算方法的探讨

为讨论不同计算方法对4类粘性土的适用性,分别用3种方法计算了各类土土压力系数和土压力强度,其结果是只考虑内摩擦角的公式法对于超固结土、正常固结土和欠固结土适用性较好,对湿陷性黄土适用性稍差;只考虑c法,对4类土均不适用;尽管等值内摩擦角法对于4类土也不适用,但考虑到等值内摩擦角法计算简便,对该法的参数选取也给出了相应的建议。     

Modeling sediment impact on the transport of fecal bacteria

Sediment storage of fecal bacteria has been observed for a long time. However, limited modeling efforts have been conducted to dynamically and explicitly study the impact of sediment on the transport of fecal bacteria. In this paper, a modeling framework based on the Environmental Fluid Dynamics Code (EFDC) model has been proposed. Free and particle-associated fecal bacteria can be modeled explicitly using the developed model. A linear adsorption relationship is incorporated into the model to obtain a sediment concentration dependent attachment ratio. The deposition and resuspension fluxes of fecal bacteria across the sediment bed–water interface are calculated coupled with the sediment deposition and resuspension flux. The model was applied to hypothetical scenarios to evaluate the sediment impacts under ideal settling and resuspension conditions. A case study was provided to test the resuspension calculation of fecal bacteria under an artificial flooding condition. Using this model, the contributions of fecal bacteria from sediment bed and from the watershed can be modeled separately and explicitly.     

加气混凝土砌块填充墙抗裂施工技术

本文分析了加气砼砌块砌体产生裂缝的原因,通过工程实例总结了裂缝的防治措施和方法。