换铺法铺设长钢轨施工工艺及造价分析

根据换铺法铺设长钢轨施工情况并结合现场施工收集的资料，针对换铺法铺设长钢轨作了简要分析探讨．并将单枕法铺设长钢轨与换铺法铺设长钢轨做了简要比较。     

中承式拱桥更换吊索工艺研究

结合某中承式拱桥更换吊索的工程实例,详细介绍了施工组织设计,阐述了施工流程及技术要点。     

重载铁路桥梁支座顶升更换施工技术

在深厚软土地区,桥下堆载与重车通行易引起桥墩沉降及倾斜,致使桥梁支座纵向位移超限。以大丽铁路某特大桥为工程依托,开展铁路桥梁支座顶升更换施工技术的应用研究。考虑运营铁路天窗期施工作业时间短、作业面狭窄、涉及专业施工内容多和安全风险高等特点,提出了用两台千斤顶同步顶升更换既有铁路桥梁支座的方案,并计算分析了千斤顶的选取、桥墩局部承压和梁缝缩小值等技术参数。结果表明:（1）采用两台DYG200型号的千斤顶,单台起重量2 000 k N,满足顶升重量要求;（2）既有桥墩顶帽C25钢筋混凝土局部承受压应力为12. 526 MPa,局部压力为885 k N,满足规范要求;（3）调整支座的梁体顶升高度为20 mm,更换支座的梁体顶升高度为88～92 mm,顶升高度满足现场施工需要;（4）顶升更换既有铁路桥梁支座施工技术对铁路桥梁支座纵向位移超限病害控制效果明显。     

LKJ车载数据无线换装系统运用研究

从LKJ数据换装场景需求、无线换装流程、系统运用场景、LKJ数据更新方式、换装监测报警、安全保障机制等方面,分析无线换装系统各功能与实际换装业务运用时的匹配关键点;以数据换装场景为基础,描述换装方式选择时机,提前换、错换、漏换报警依据,数据换装时间范围卡控原理;分析无线换装系统在提升工作效率及经济、安全效益方面带来的优势,为全路全面开展无线换装系统实施落地提供参考。     

栈桥式平移法换架高速铁路简支箱梁技术研究

随着我国高速铁路桥梁的快速发展,各种灾害对其造成破坏的可能性增高。为了能够有效应对未来高速铁路桥梁灾后的快速保障需求,重点研究将来高速铁路桥梁遭受灾害损毁破坏后,在通过抢修钢梁保证临时限速通车的情况下,采用栈桥式平移法实现新制混凝土箱梁和临时抢修钢梁换装施工的技术方案。主要研究内容包括:总体技术方案、施工场地布置方案、施工设备的设计方案和换架梁施工工艺等,并总结该项技术的关键技术要点和方案的适应性。通过研究说明,栈桥式平移法是一种安全可靠、成本低廉、快速有效的换架梁施工技术,有助于推动我国高速铁路桥梁灾后应急保障技术的发展,并为同行提供有价值的参考。     

软弱土质在地基处理中的应用

提出了软土、盐渍土地基路基换填处理方案,在实际工程中采用粒料石灰土换填层和土工布、荆笆帘、粒料换填层两种换填层结构处理软土盐渍地基.     

粉喷桩应用若干问题的探讨

结合广东地区粉喷桩的经验,探讨了粉喷桩处理软基的若干问题。     

Construction Techniques for the Small-radius Curved Shield Tunnels in Water-rich Fractured Stratum with High Pressure北大核心CSCD

A variety of construction problems, such as bad cutting effects of cutters, unreasonable boring parame- ters and blowout, are often encountered during shield tunnelling under unfavorable geological conditions. Aimed at these construction difficulties of high pressure, abundant underground water, fractured rock stratum, long distance and small-radius curves of Fuzhou metro, the mechanical behaviors of cutting tools were analyzed through theoreti- cal calculations of cutter cutting force, then the reasonable cutter configuration, tunneling parameters and the proper time for cutter replacement were presented. Some measures, such as screw conveyor renovation, mucking control and lowering of groundwater, were adopted for controlling blowout based on practice. The stability of excavation face was analyzed by numerical simulation, and the measures for shield boring and posture control in the long distance and small radius curved tunnels were summarized. The conclusions are as follows: 1) when shield machine is driven in fractured stratum, the effect of lateral impact force produced by spalling rock on cutter will be very large and rein- forcement is needed for cutter; 2) cutter replacement should be taken at proper time based on muck samples in con- ditions of increasing of total shield thrust by 4 000-7 000 kN, cutter torque by 1 000-1 500 kN•m and driving speed smaller than 10 mm/min; 3) adopting screw conveyor device with innovative anti-blowout devices and control measures for ground precipitation and mucking, it controls blowout effectively; 4) the maximum axis offset and the height offset of segment meet the requirements of shield construction specifications during shield construction of long distance small-radius curved tunnel. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Temperature Measurements and Tail Brush Replacement using Frozen Liquid Nitrogen for the Nanjing Weisanlu Tunnel北大核心CSCD

A scheme for stopping water by freezing liquid nitrogen and replacing the tail brush is presented in light of the situation encountered at the Nanjing Weisanlu river-crossing tunnel, a long-distance shield driving tunnel characterized by serious water leakage, sand gushing and water inflow at the shield tail brush. The law of the tempera-ture change of the master outlet circuits and each branch circuit when using liquid nitrogen freezing to stop water un-der high water pressures and the temperature change law for the soil body at different depths are analyzed. The re-sults show that: the temperature difference of the liquid nitrogen is large at the inlet and outlet of the freezing pipe,and it reaches around 35℃ after 6 days; the temperature drops fastest in the pebble layer, and the second fastest in the gravel sand layer, with the temperature cooling slowest in the silty fine sand layer; the average velocities at the frontal surface of the frozen soil in the pebble layer, gravel sand layer and silty fine sand layer are 15.5 cm/d, 12.5 cm/d and 8.3 cm/d, respectively, within the range 600 mm away from the frozen pipe; and affected by heat and air convection in the tunnel, the temperature at the junction of the segment and soil is higher than that in the soil layer.A complete frozen wall takes shape after 13 days of liquid nitrogen freezing, and tail brush replacement takes 22 days from freezing. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

焊接线外置机器人抓手切换自动化方案

文章基于便捷性、安全性、可靠性与高效性的生产理念,通过定位装置精确定位抓手 存放车,并进一步精确定位抓手,确保抓手的位置精度,保证机器人每次能够通过固定的运行轨迹来拾取或放置抓手。通过气路接通装置,代替人工接气,实现抓手存放车气路能够自动安全快速地通气,从而实现抓手存放车气动机构打开与闭合;通过无线耦合器,解决抓手 存放车与线体的信号连接与传输的问题,实现可编程逻辑控制器电气控制;通过程序闭环控制,实现严格按照步骤及信号反馈进行下一步动作,确保安全高效切换,最终达到提升生产 效率,降低工人作业强度,提高设备开动率的目的。