Highway Tunnel Blasting Vibrations and Cracking of Adjacent Residential Houses北大核心CSCD

A systematic analysis and discussion of the causes of house cracking are conducted by testing the blast vibration velocity of typical neighboring houses, analyzing the types of house cracking, monitoring the characteris-tics of house cracks and calculating the temperature stress at the roof and wall based on an assessment of highway tunnel blasting vibrations leading to cracking of neighboring houses. The results show that the main cause of house cracking adjacent to the tunnel is temperature stress, not blasting vibration. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Evaluation of CO2 emissions from railway resurfacing maintenance activities

This paper is the world first to investigate the CO₂ impact of railway resurfacing in ballasted track bed maintenance. Railway resurfacing is an important routine maintenance activity that restores track geometry to ensure safety, reliability and utility of the asset. This study consisted of an extensive field data collection from resurfacing machineries (diesel-engine tamping machines, ballast regulators and ballast stabilisers) including travel distances, working distances, fuel consumption and construction methodologies. Fuel consumption was converted to a kg CO₂/m using the embodied energies of diesel. Analyses showed that tamping machines emitted the highest CO₂ emissions of the resurfacing machineries, followed by ballast regulators and ballast stabilisers respectively. Tamping machines processed 4.25 m of track per litre of diesel, ballast regulators processed 6.51 m of track per litre of diesel and ballast stabilisers processed 10.61 m of track per litre of diesel. The results were then compared to previous studies and a rigorous parametric study was carried out to consider long-term resurfacing CO₂ emissions on Australian railway track. The outcome of this study is unprecedented and it enables track engineers and construction managers to critically plan strategic rail maintenance and to develop environmental-friendly policies for track geometry and alignment restoration.     

沉船水下开孔抽油技术研究现状与展望

沉船中常含有大量的残油,对海洋环境造成巨大威胁,因此快速安全得对沉船进行开孔抽油作业具有重要意义。通过对现有沉船水下开孔抽油技术装备的分类综述和分析,剖析国内外作业装备的优缺点,并总结出水下开孔抽油中涉及的关键技术及其特点,根据现有作业方法与研究成果,提出了沉船水下开孔抽油技术未来研究发展方向,水下开孔抽油能力的提升是我国发展战略的重要组成部分,也为我国“海洋强国”战略的实现提供了可靠的技术保障。     

疏浚土长距离管道输送技术在环保疏浚工程中的应用

滇池草海清淤工程疏浚区域分为3个片区,疏浚面积70万m2,工程量220万m3,输送距离8～15 km。针对输泥路径上的场地限制问题,进行了长距离输送方法的分析及研讨,结合施工现场实际情况,决定采用接力泵输送方法,实现了长距、高效输送疏浚土。     

某住宅小区雨污混接改造技术方案的探索

在上海市全面开展水环境整治的背景下,以青浦区某住宅小区雨污混接改造工程为例,分析探讨该小区排水系统存在的主要问题,提出该小区雨污混接改造的具体实施方案,以及海绵城市设计方案。其成果可为类似工程项目提供借鉴。     

排水泵站集水池施工技术

本文结合工程施工经验，论述排水泵站主要施工措施，介绍泵站施工工艺，并就常见混凝土施工质量缺陷提出防治补救措施。     

一种可靠的防止桥头跳车的施工方法

根据同三公路起点段施工经验,介绍了水撼砂砾振捣密实法的施工工艺。这种方法具有成形快、施工时间短、成本低廉、工后可靠度高的特点。     

广州地铁三号线天五区间泵房施工技术

 地铁建设中隧道联络通道是重点之一，而在软弱地层中进行联络通道底部泵房开挖则是联络通道施工的关键。结合广州地铁三号线天—五区间二号联络通道泵房的施工，介绍了在富水软弱地层下的土体注浆加固法结合暗挖法的实际应用。     

下穿式铁路立交引道排水设计

针对城市中的下穿式立交引道,采用渗水管、雨水沟和排水管相结合的排水方式,对地下水和路面雨水进行收集后,通过雨水泵站提升后排入河道。该文结合工程,介绍了设计方法,可供类似工程参考。     

客运专线箱梁C50高性能混凝土配合比设计与泵送施工

结合高耐久、高性能混凝土配合比的设计方法和聚羧酸系外加剂的特点,以及客运专线所处施工环境原材料的实际现状,介绍客运专线预应力混凝土箱梁C50高性能混凝土的配合比设计方法,提出了其施工中应注意的一些事项,以供参考。