Based on the construction practice of steel cofferdam for pier base of main pier no . 6 close to the pylon of sutong bridge , the key techniques for design and construction of the deep water double - wall steel cofferdams of the bridge are described 摘要以苏通大桥近塔墩主6号承台钢围堰工程实践为基础，介绍该桥深水双壁钢围堰设计、施工的关键技术。
This thesis depicts the application of pvc - u double - wall corrugated pipe production quality control system in actual production , which indicates that the system has the capacity to seek and analyze the potential disqualification in production process so that it has greatly improved the production process and gained favorable effects 本文描述了pvc - u双壁波纹管生产质量控制系统在实际生产中的应用，表明该系统能够有效地查找和分析出生产过程中的潜在不合格，可以改善生产过程质量，获得良好的质量控制效果。
Under the function of big pressure and dynamic load , the grains may be moved which may cause the soil body distortion . at present , the relatively ripe methods of drill in gravel layer are mostly double - wall drill pipe reverse circulation drilling , auger stem breast wall drilling and down - the - hole hammer follow down drilling 论文根据jsl ? 30型砾石钻机潜孔锤同心跟管钻具结构,采用程序计算得到了钻杆内各深度处压力分布、钻头压力降、环形空间压力分布及空气流速分布。
This paper gives an account of the construction schemes of building artificial islands and sinking concrete cofferdams for shoal piers no . 53 and no . 59 , and the construction schemes double - wall steel cofferdams for deep water piers no . 54 ~ 58 of hengyang xiangjiang river bridge on wuhan - guangzhou passenger dedicated railway 摘要介绍武广客运专线衡阳湘江特大桥53号、 59号浅滩墩采用的筑岛、下沉混凝土围堰施工方案，以及54 ~ 58号深水水中墩采用的双壁钢结构围堰施工方案。
On the basis of quality control theory - statistical process control ( spc ) and process capability index ( cpk ) are integrated with mathematical statistics technology to execute the comprehensive quality control over the whole production process of plastics pipe ( pvc - u double - wall corrugated pipe ) . aiming at each process characteristics of the production , it has adopted different controlling models and formed a set of the production quality control system of pvc - u double - wall corrugated pipe . this thesis points out the structure principal and project ideas of the production quality control system of pvc - u double - wall corrugated pipe , which is based on computer technology 运用质量控制理论? ?统计过程控制( spc )和工序能力指数( cpk ) ，结合数理统计技术，对塑料管材( pvc - u双壁波纹管)整个生产过程质量进行全面控制。针对pvc - u双壁波纹管生产线的各个工序特点，采用不同的控制模式，形成了一套pvc - u双壁波纹管生产质量控制系统。并提出了基于计算机技术的pvc - u双壁波纹管生产质量控制系统的构建原理和设计思路。
