Stress integration approach to evaluate damping ratio in torsional tests

The complexity of determining strain associated with shear modulus and damping ratio in torsional tests has been resolved by means of several approaches. The stress integration approach is adequate when generating the plots of equivalent radius ratio versus strain more effectively over any range of strains in resonant column and torsional shear (RC/TS) tests. The stress integration approach was applied for hyperbolic, modified hyperbolic, and Ramberg–Osgood models in evaluating damping ratio. This study showed that using a single value of equivalent radius ratio in evaluating damping ratio is not appropriate. The combined hysteretic‐nonviscous damping model was developed and employed to consider the increased damping behavior at small strains using the stress integration approach. The results suggest that adding viscous behavior has no significant effect strain calculations in RC/TS testing. Copyright © 2010 John Wiley & Sons, Ltd.     

关于风积砂地基扩展基础抗拔计算公式的探讨

利用风积砂地基抗拔室内模型试验资料，通过对抗拔土体破坏机理的全面分析，提出了土体形成极限承载力的三个受力过程，建立了扩展基础抗拔承载力计算的基本公式，与目前其它计算方法比较，成果精度提高很多倍，而且适用范围不受深宽比限制，便于推广应用。     

复合地基技术及应用

提出了复合地基的设计原则，对复合地基承载力计算、变形计算、柔性垫层进行了探讨，提出了复合地基技术需研究的问题。     

沉降监测基准网与监测网精度探讨

为了保证建筑物在沉降过程中变形观测点的观测成果的连续性、可比性，对沉降监测中基准网与监测网的观测精度匹配问题进行了详细的探讨，得出了有参考价值的结论。     

斜交桥渡的壅水及设计计算

基于斜交桥渡的水流特点及尾流扩散理论,推导了桥前计算塑水的迭代公式以及相应孔径设计的表达关系,经计算,壅水的计算值与某山区斜交桥渡的试验资料吻合很好.     

A GIS-based method for flooded area calculation and damage evaluation

Using geographic information system to study flooded area and damage evaluation has been a hotspot in environmental disaster research for years. In this paper, a model for flooded area calculation and damage evaluation is presented. Flooding is divided into two types: ‘source flood’ and ‘non-source flood’. The source-flood area calculation is based on seed spread algorithm. The flood damage evaluation is calculated by overlaying the flooded area range with thematic maps and relating the result to other social and economic data. To raise the operational efficiency of the model, a skipping approach is used to speed seed spread algorithm and all thematic maps are converted to raster format before overlay analysis. The accuracy of flooded area calculation and damage evaluation is mainly dependent upon the resolution and precision of the digital elevation model (DEM) data, upon the accuracy of registering all raster layers, and upon the quality of economic information. This model has been successfully used in the Zhejiang Province Comprehensive Water Management Information System developed by the authors. The applications show that this model is especially useful for most counties of China and other developing countries.     

云南元江金矿矿床模型及矿产经济

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方向前方交会严密精度评定方法的研究

本文地针对方向前方交会精度评定中的不足之外，推导出了二测站和三测站方向前方交会同时考虑测量误差和测站点位误差时交会点严密的精度评定公式，从理论上完满地解决了方向前方交会的精度评定问题。     

经纬仪实时空间测量系统研制与应用

本文介绍了经纬仪实时空间测量系统的基本原理和系统配置,描述了系统的测量精度和误差影响情况,介绍了系统所具有的功能;通过对标准量具的检测,证明该系统是可靠的,对特种精密工程测量的精度要求是可以满足的,在其它领域也有广泛的应用前景。     

特大型桥梁施工高程控制网布设与跨河水准测量实验

本文根据特大型桥梁工程施工对高程控制的精度要求，推算高程控制网的必要精度，提出了虎门大桥施工高程控制网的布设和观测方案，根据经济性原则，进行跨河水准测量实验，并对实验数据进行分析处理，研究水准光学测微法在长距离等级跨河水准测量中应用的可行性。