共查询到20条相似文献,搜索用时 125 毫秒
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针对真空预压地基边缘处理效果,结合温州永强机场飞行区改扩建工程地基处理,在改扩建工程所在场区选出两块试验区Z1和Z2,Z1区周边打设淤泥搅拌桩密封墙,Z2区周边采用不打设密封墙。全程监测两块试验区边缘区域地基土层在真空预压处理过程中膜下真空度、地表沉降、深层位移的数据。在边缘区域地基真空预压处理前后进行十字板剪切试验测定土体强度,并比较两块试验区边缘区域固结度与十字板剪切强度,分析两块试验区边缘区域地基预压效果的优劣。通过试验数据分析,可以表明:周边打设密封墙的Z1区边缘区域地基的真空预压效果明显优于不打设密封墙的Z2区边缘区域。 相似文献
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无膜真空预压技术是近年应用于软土地基加固工程的一项新技术。具有以泥代膜、以管代砂、单块加固面积大、密封沟工程量小、成本低、施工速度快等优点。本文结合厦门保税区二期工程的施工,简要介绍无膜真空预压技术在软基处理工程的应用。 相似文献
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介绍黄骅港一期工程的软基处理,从后方区的真空预压试验到堆场区的大面积应用,这是真空预压首次在不设密封墙的情况下,用于高渗透性土层条件的地基加固.着重说明在黄骅港这种地质条件下真空预压工法的采用以及质量控制方法. 相似文献
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艉轴密封装置是船舶推进系统的关键组成部分,其密封性能的优劣直接影响船舶航行的安全性与可靠性。以船舶艉轴机械密封环为研究对象,基于热-结构耦合模型对比分析了赛龙、聚四氟乙烯和碳石墨这3种材料密封环的温度场和结构场差异,并提取动、静环接触面各节点的温度和压力分布。结果表明:3种材料密封环最高温度和接触压力均处于密封环内侧,并由内而外逐渐减小,相同位置处碳石墨密封环的端面温度小于赛龙与聚四氟乙烯密封环,且接触压力较大。综合密封台架试验验证,碳石墨密封环端面温度和摩擦系数较低于另外两种材料密封环,密封性能较好。研究结果对于不同材料配对的船舶艉轴机械密封环材料的筛选具有一定的指导意义。 相似文献
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电缆是供电设备与用电设备之间连通的桥梁,起到传输电能的作用,电缆一般穿过墙体中预埋钢套管结构连接供电设备和用电设备.在工程实践中经常出现电缆和钢管间隙封堵不严密,雨水通过间隙进入变电所内,导致变电所内电缆沟出现大量积水,给日常运行管理造成不便,对电缆和变电所内电气设备安全运行造成威胁.施工过程中,受施工环境、自然条件限... 相似文献
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An improved spherical, movable transfer skirt for autonomous submersibles has been devised. It was designed to permit the
transfer of equipment and personnel from a submersible to the pressure chamber of an oil storage sea-bed structure. It also
allowed mating at large vertical angles while the submersible remained horizontal. Seal failure modes and procedures for analyzing
the sealing ability of the mating flange of the hull transfer skirt were thoroughly analyzed using conservative estimation
methods. In the analysis, sea currents and mating angles were considered. Results showed that when considering the effects
of currents, spherical radius and mating angle, their influence on seal ring failure should be considered first. The critical
mating depth for a seal ring failure was larger than for either sliding or rotational failure modes. The critical mating depth
can be used to determine the mating method of the submersible. The analytical procedures and results can be used as a reference
for the design of spherical hull transfer skirts. 相似文献
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密封件是军用电子设备的重要零件之一,其设计质量的好坏直接影响到设备的三防性能.分析了密封材料的选用问题,阐述了橡胶密封原理,讨论了密封件具体的结构形式以及密封件的安装问题,最后给出了设计实例. 相似文献
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To overcome the current difficulties of high-precision machining and the high manufacturing and maintenance costs of spherical seals for deep-water drilling ball joints, a new spherical seal technique is proposed in this paper. The spherical seal is mainly composed of silicone rubber and polytetrafluoroethylene (PTFE). Rational structural design makes the seal independent from the ball and other components, making it easy to replace if leakage occurs at its surface. PTFE can elastically deform over a certain deformation range, which guarantees that two sealing surfaces fit tightly together. O-Ring and PTFE elasticity makes up for any lack of accuracy during spherical machining and decreases the machining precision requirements for spherical surfaces. Using a finite element technique and nonlinear theory, the performance of the spherical seal under the influence of various factors is determined. The results show that the spherical seal designed in this paper exhibits excellent sealing performance under low-temperature and high-pressure conditions. The spherical seal, a combination of an O-ring and PTFE, has the advantages of cheap manufacturing and maintenance costs and excellent sealing performance. 相似文献
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To overcome the current difficulties of high-precision machining and the high manufacturing and maintenance costs of spherical seals for deep-water drilling ball joints, a new spherical seal technique is proposed in this paper. The spherical seal is mainly composed of silicone rubber and polytetrafluoroethylene(PTFE). Rational structural design makes the seal independent from the ball and other components, making it easy to replace if leakage occurs at its surface. PTFE can elastically deform over a certain deformation range, which guarantees that two sealing surfaces fit tightly together. O-Ring and PTFE elasticity makes up for any lack of accuracy during spherical machining and decreases the machining precision requirements for spherical surfaces. Using a finite element technique and nonlinear theory, the performance of the spherical seal under the influence of various factors is determined. The results show that the spherical seal designed in this paper exhibits excellent sealing performance under lowtemperature and high-pressure conditions. The spherical seal, a combination of an O-ring and PTFE, has the advantages of cheap manufacturing and maintenance costs and excellent sealing performance. 相似文献