静压桩在高层商住楼中的应用

本文以深圳市俊安苑住宅小区5幢高层商住楼静压桩施工为例，介绍静压桩机的选择、静压桩施工要点、静压桩质量检测的应用体会。     

Orthonormal residuals in geostatistics: Model criticism and parameter estimation

In linear geostatistics, models for the mean function (drift) and the variogram or generalized covariance function are selected on the basis of the modeler's understanding of the phenomenon studied as well as data. One can seldom be assured that the most appropriate model has been selected; however, analysis of residuals is helpful in diagnosing whether some important characteristic of the data has been neglected and, ultimately, in providing a reasonable degree of assurance that the selected model is consistent with the available information. The orthonormal residuals presented in this work are kriging errors constructed so that, when the correct model is used, they are uncorrelated and have zero mean and unit variance. It is suggested that testing of orthonormal residuals is a practical way for evaluating the agreement of the model with the data and for diagnosing model deficiencies. Their advantages over the usually employed standardized residuals are discussed. A set of tests are presented. Orthonormal residuals can also be useful in the estimation of the covariance (or variogram) parameters for a model that is considered correct.     

对城市地震科普知识宣传方法与效果的调查与分析

本文以绵阳市为例,采用随机抽样的方式对3500余名城市不同层次的人员进行问卷调查,还对目前地方地震机构普遍采用的地震科普知识宣传方法进行了社会检验,综合评判与分析。指出了当前地震宣传工作与社会需求之间的偏差,提出了城市地震科普知识宣传的最佳方法和较好组合模式,以实现目前在人、财、物力十分有限的情况下,发挥最佳经济和社会效益。     

缩套型高温高压三轴室热应力分析

以８００ＭＰａ高温高压三轴室为例，介绍了简体热应力计算方法和结果。分析讨论了热应力对筒体安全性的影响，指出高温差低载荷是最危险的情况，并提出预防与解决的方法。     

软土地基上土工结构物的离心模拟试验

由于离心模拟试验所提供的高加速度可以模拟重力加速度,而引起土工结构物的稳定性和地基变形问题,主要原因正是由于地基不能适应上部结构物的自重,因而土工离心试验能最大限度地逼近现场试验,试验结果已为设计工程师所采用。本文主要介绍4个沿海工程如何利用离心模拟试验来检验这些工程的稳定和变形。     

Validity of uniaxial compression tests for indirect determination of long term strength of rocks

Summary The validity of using laboratory uniaxial compression tests to determine the long-term strength of rock is considered. Results of an experimental study on three types of rocks are analysed, and the usefulness and limitations of the approach are discussed. Different methods of estimating strength are used and the results compared.     

Polyester mooring for the Mad Dog spar—design issues and other considerations

The Mad dog project will use a polyester mooring system on the drilling and production truss spar. This will be the first use of a permanent polyester mooring system on a Floating Production System (FPS) outside of Brazil and the first time polyester has been used on a spar. As such, there were many challenges, which include:

• Regulatory approval.

• Designing a mooring system which is dominated by current loadings.

• Largest polyester rope break load ever required.

• Rope design qualification and testing.

• Quality control and assurance.

• Inspection, Maintenance, Repair and Retirement (IMRR) of such a mooring system.

This paper will focus on the design issues, rope design, manufacturing, qualification and testing, and the IMRR plan that was developed to provide the assurance that the polyester mooring system could be safely operated over the 20-year field life.     

Driving behavior of stepped and tapered offshore piles due to hammer blows

Abstract

In this article, the drivability of stepped and tapered offshore piles with the same length and volume has been investigated under hammer blows. To justify the obtained results from field testing and numerical methods, this pile driving procedure has been analyzed and discussed with wave propagation mechanism. It will be shown that tapered pile can be confidently idealized as a number of prismatic segments connected rigidly to each other. This is an interesting finding that fully tapered or stepped piles have a better performance in pile driving and enable users to apply simple one dimensional numerical analysis for simulating pile drivability.