Optimization of site exploration program for improved prediction of tunneling-induced ground settlement in clays     

《Computers and Geotechnics》2014

Excessive settlement caused by tunneling during construction often damages adjacent infrastructures and utilities. Such excessive settlement can also present a challenge in the maintenance of subways during their operation. Thus, it is important to be able to accurately predict tunneling-induced settlement. The uncertainties in geotechnical parameters, however, can lead to either an overestimation or an underestimation of the tunneling-induced settlement. Such uncertainties can arise from many sources such as spatial variability, measurement error, and model error; in this paper, the focus is on the geotechnical parameters characterization from site exploration. The goal here is to determine an optimal level of site exploration effort so that effective predictions of the tunneling-induced settlement in clays can be achieved. To this end, a Monte Carlo simulation-based numerical model of site exploration is first established to generate artificial test data. Then, a series of parametric analyses are performed to investigate the relationship between the level of site exploration effort and the accuracy of the tunneling-induced ground settlement prediction. Through the assumed different levels of site exploration effort, statistics of soil parameters are estimated using the maximum likelihood method and the tunneling-induced ground settlement is then analyzed using the probabilistic method, and finally the effect of site exploration effort is assessed. The knowledge generated from this series of analyses is then used to develop the proposed framework for selecting an optimal site exploration program for improved prediction of the tunneling-induced ground settlement in clays. Examples are presented to illustrate the proposed framework and demonstrate its effectiveness and significance.  相似文献   

Underground excavation shape optimization considering material nonlinearities     

《Computers and Geotechnics》2014

The shape of an underground opening is a major factor influencing the stability of the underground excavation. Obtaining an optimized shape is significant in civil and mining engineering applications for increasing stability and reducing costs. This paper presents an updated method for finding the optimal shape of an underground excavation using the latest bi-directional evolutionary structural optimization (BESO) techniques considering material nonlinearities. Recent development in the BESO applications to underground excavation is discussed through illustrated examples. Details are given of the BESO method used to finding the optimal shape based on the global stiffness. The methodology of the stiffness based optimization techniques is described with examples of applications to underground excavation. Applications to underground void structures, such as cavern and tunnel, as well as underground solid structure such mine pillar are demonstrated. It is concluded that stiffness based optimization techniques are applicable to underground excavations and practical shape of an excavation can be generated as a result of the BESO application.  相似文献   

A decision support system for floating platform design     

J. Vasconcellos 《Ocean Engineering》1999,26(9):865

This paper describes a methodology developed for the preliminary design of floating production platforms. The preliminary design approach interlinks the mathematical design model with global optimization techniques. To illustrate the design procedure, the initial intermediate and final results are presented. They provide a clear understanding of the mathematical model and the decision support system. The preliminary design approach described here is based on the commercial software which is interfaced to what is called the FPS system and linked to a SEARCH package for design solutions. The paper summarizes the preliminary design approach, the mathematical model optimization and presents semisubmersible and TLP platform examples.  相似文献   

青海省地震局网络优化及技术应用     

孙凯 《高原地震》2008,20(3):60-64

通过对青海省地震局已建成的互联网络中存在的若干问题,提出对现有网络进行优化和改造的思路,旨在提高网络的传输性能和工作效率。  相似文献   

The role of observations in the inverse analysis of landslide propagation     

《Computers and Geotechnics》2017

Model calibration is usually based on trial-and-error procedures that, in turn, rely on expert judgment or previously acquired experiences for similar phenomena. Efficient and reliable procedures for model calibration of the propagation stage of landslides are still needed. This paper addresses this issue by proposing an inverse analysis procedure and applying it to the case history of a short run-out landslide triggered by a rising perched water table after a heavy rainfall. It focuses on the key role played by the field observations used to set up the inverse analysis, and evaluating the reliability of the numerical simulations. It also investigates the effect of different types of optimization parameters on the inverse analysis results, referring to a mixed-phase model or to a two-phase model for the propagating soil. Several sets of observations are used; all of them refer to the soil deposit thickness at the end of propagation, but differ in both location and number of the adopted values. The numerical analysis of the case history is performed through the academic “GeoFlow_SPH” model, and model calibration by inverse analysis is conducted using the “UCODE” software. The results obtained are discussed with the aim to provide practical criteria to identify the minimum amount of information required for a satisfactory model calibration.  相似文献   

控制论与人工影响天气 III: 自然控制论在人工增雨作业中的应用框架   总被引：3，自引：2，他引：1  

曾庆存  吴琳  洪钟祥 《气候与环境研究》2012,17(6):986-990

应用自然控制论的理论方法,提出人工增雨作业和效果检验的框架.它将事前和作业进行过程中的观测和预报、调控方案(滚动式的和有反馈回路的)、作业和效果检验紧密联系成一个整体系统,将调控方案提为最优化问题,并把不断的观测资料同化到滚动式预报模式和求优化之中.所提出的一种效果检验方法是比较客观和定量的.  相似文献   

天津地区地震地下流体观测网调整与优化的思考   总被引：2，自引：0，他引：2  

邵永新  马建英  王建国  吴强 《地震研究》2009,32(2)

从天津地区地震地下流体观测网映震能力的角度出发,讨论了其发展问题.在天津地区地下流体观测网映震效果不理想的条件下,2007年又发生了王3井断流、王4井井压加速下降情况,因此,应对天津流体观测网的观测进行调整:在数最上应以水物理参量的观测为主,水化学观测为辅;在观测井孔的深度上,采取浅井(咸水井)、中深井和深井相结合的方式,建设一个立体型的观测网,尤其应注意对咸水层的利用;采取与相关单位合作联合观测的方式,资料共享.  相似文献   

Investigation on the energy absorption performance of a fixed-bottom pressure-differential wave energy converter     

《Applied Ocean Research》2017

In this article, we investigate the energy absorption performance of a fixed-bottom pressure-differential wave energy converter. Two versions of the technology are considered: one has the moving surfaces on the bottom of the air chambers whereas the other has the moving surfaces on the top. We developed numerical models in the frequency domain, thereby enabling the power absorption of the two versions of the device to be assessed. It is observed that the moving surfaces on the top allow for easier tuning of the natural period of the system. Taking into account stroke limitations, the design is optimized. Results indicate that the pressure-differential wave energy converter is a highly efficient technology both with respect to energy absorption and selected economic performance indicators.  相似文献   

基于PSO的地震盲反褶积方法     

蔡连芳  田学民 《地球物理学进展》2012,27(3):1116-1122

本文基于地层反射系数非高斯的统计特性,在反褶积输出单位方差约束下,将反褶积输出的负熵表示为非多项式函数,作为盲反褶积的目标函数,然后采用粒子群算法优化目标函数寻找最佳反褶积算子,实现地震信号的盲反褶积.数值模拟和实际资料处理结果表明,与传统反褶积方法相比,本文方法同时适应于最小相位子波及混合相位子波的反褶积,能够更好地从地震数据中估计反射系数,有效拓宽地震资料的频谱,得到高分辨率的地震资料.  相似文献   

Assessment and prioritization of soil erosion triggering factors using analytical hierarchy process and Taguchi method   总被引：1，自引：0，他引：1  

Mehdi Hayatzadeh  Vahid Moosavi  Ramyar Aliramaee 《国际泥沙研究》2023,38(3):396-404

The main aims of this study are assessing some factors which affect the soil erosion process and evaluating the results of an analytical hierarchy process(AHP) method using the Taguchi method. Firstly, the weights for those factors and levels affecting soil erosion were determined by the AHP method. The determination of weights was based on the opinions of academic researchers, experts, middle managers,and members of the Soil and Water Research Centers in Iran. Secondly, an L32 Taguchi orthogona...  相似文献