Behavior of Pile Groups under Lateral Load

Based on investigation and model tests, and in combination with the research work on group effect for pile groups under lateral loads relating to the code of fixed offshore platforms, a series of studies have been performed on the behavior and failure mechanism of laterally loaded pile groups, critical pile spacing inducing group effect, lateral bearing capacity of pile groups and its main influence factors, the stress-strain relationship for single piles and pile groups and so on. Some new laws about non-uniformity of load distribution in the longitudinal direction of pile groups and load-deflection (p - y) curves for pile groups have been discovered, and an empirical formula is presented in order to remedy the defect of current calculating methods at home and abroad. These results can be used for reference in the design of pile foundation under lateral loads.     

海上平台桶形基础模型压力压贯与负压沉贯试验研究

介绍了海上平台桶形基础模型（模型桶）压力压贯和负压沉贯的试验概况,对比分析了两者贯入力的巨大差异和产生的原因,给出了模型桶压力压贯中贯入深度与压力的关系,负压没贯负压与贯入深度,抽吸泵流量,基土渗流量,桶内土塞隆起之间的关系,试验结果表明,负压沉贯可以大大降低以砂质粉土为基土的土抗力,为在胜利油田类似基土海域海上平台应用桶形基础提供了试验依据,为海上现场导管架桶形基础平台的安装就位施工和控制提供了     

大陆岩石圈在张裂和分离时的变形模式

通过对南海南北共轭边缘地壳剖面的对比研究,发现大陆岩石圈的物理性质是分层的：上、中地壳呈脆性,下地壳表现出塑性,而岩石圈上地幔则仍呈脆性。因此,在它受张性应力场作用时,其变形和破裂分离方式也是分层进行的：上、中地壳能发生犁式断裂,产生的断块沿断面转动在地表产生一系列半地堑,并使地壳厚度减薄;如拉张应力继续作用时,上、中地壳将沿犁式断裂被拉开,从而形成上、下板块边缘,并彼此分开。下地壳则发生塑性变形,使地壳厚度减薄,并最终将其拉断。岩石圈上地幔亦可产生陡倾断裂,形成的断块沿断面转动亦使其厚度减薄,并最终沿陡倾断裂被拉断。这就是我们称之为岩石圈变形和破裂分 离时的分层变形及分层破裂分离模式。     

Shear Failure of a Clamped Dented Tubular Beam Under Lateral Impact

- The shear failure of a rigid-plastic dented clamped tubular beam under the lateral impact of a mass is investigated. Both the denting and the impact point are in the middle span of the beam. It is assumed that denting does not spread during the shear sliding. Numerical results show that the axial force and lateral deflection of the beam are very small at the moment of the occurence of shear failure, which means that the finite deformation effect can be neglected in the shear failure analysis. Also, some aspects of the initial impact energy are investigated.     

不同软基处理方法适用性比较

总结分析了国内外现有的软土地基处理的各种方法。通过对采用不同方法进行软基处理的工程实例处理效果的定量对比，发现不同软基处理方法的适用性差异很大，多数工程中仅用一种方法很难达到设计要求，而两种或多种方法联合则可望取得更好的效果。     

桶形基础平台三维有限元稳定性分析

以我国第一座桶形基础采油平台工程实例为原型，采用三维有限元计算方法对桶形基础稳定性分析。平台在波浪、风等荷载作用下，其稳定性不仅与平台的整体结构有关，而且与桶形基础及其周围土体相互作用相关。在计算中，利用薄层摩擦单元模拟土与结构间的相互作用，取得了很好的效果。分析结果表明桶形基础采油平台在设计条件下运行是较为稳定的。     

南海罗斯贝变形半径的地理及季节变化

根据南海 1°× 1°网格的标准层季节平均温、盐度资料 ,在未引入Boussinesq近似条件下 ,采用改进的Thompson Haskell算法求解线性化斜压海洋水平大尺度波的垂直结构方程 (重力内波方程 ) ,从而得到了南海各网格点的第一斜压重力波相速度和相应的罗斯贝变形半径 ,并探讨其地理分布和季节变化特征 ,以期有助于南海环流和中尺度涡旋以及有关海洋侧边界效应的研究。     

新建水坝对下游已建水工建筑物的影响分析

分析了新建水坝及社会经济发展因素对坝下游水流及泥沙的影响，用一个简易河床模型来说明新建大坝后下游河床的演变规律，通过坝下游河床一般演变分析来阐述局部冲刷对已建水工建筑物基础的影响及对已建水工建筑基础的防护措施。     

动态基准实时测量系统的开发与应用

介绍了动态基准实时测量系统的硬件组成、站点上全站仪棱镜组合安装与检测方法、系统软件的开发及特点，最后对系统在广州地铁某地铁站结构变形自动监测中的应用情况进行了阐述。通过实际应用表明该系统能应用在自动化、高精度的变形监测领域。     

Two-Dimensional Mathematical Model of Tidal Current and Sediment for Oujiang Estnary and Wenzhou Bay

A 2-D mathematical model of tidal current and sediment has been developed for the Oujiang Estuary and the WenzhouBay. This model accomodates complicated features including multiple islands, existence of turbidity, and significant differ-ence in size distribution of bed material. The governing equations for non-uniform suspended load and bed load transport arepresented in a boundary-fitted orthogonal curvilinear coordinate system. The numerical solution procedures along with theirinitial conditions, boundary conditions, and movable boundary technique are presented. Strategies for computation of thecritical condition of deposition or erosion, sediment transport capacity, non-uniform bed load discharge, etc. are suggested.The model verification computation shows that, the tidal levels computed from the model are in good agreement with the fielddata at the 18 tidal gauge stations. The computed velocities and flow directions also agree well with the values measuredalong the totally 52 synchronously observed verticals distributed over 8 cross sections. The computed tidal water throughputsthrough the Huangda‘ao cross section are close to the measured data. And the computed values of bed deformation fromYangfushan to the estuary outfall and in the outer-sea area are in good agreement with the data observed from 1986 to 1992.The changes of tidal volumes through the estuary, velocities in different channels and the bed form due to the influence of thereclamation project on the Wenzhou shoal are predicted by means of this model.