Selection of sand models and identification of parameters using an enhanced genetic algorithm          下载免费PDF全文

Yin‐Fu Jin  Zhen‐Yu Yin  Shui‐Long Shen  Pierre‐Yves Hicher 《国际地质力学数值与分析法杂志》2016,40(8):1219-1240

Numerous constitutive models of granular soils have been developed during the last few decades. As a consequence, how to select an appropriate model with the necessary features based on conventional tests and with an easy way of identifying parameters for geotechnical applications has become a major issue. This paper aims to discuss the selection of sand models and parameters identification by using genetic algorithm. A real‐coded genetic algorithm is enhanced for the optimization with high efficiency. Models with gradually varying features (elastic‐perfectly plastic modelling, nonlinear stress–strain hardening, critical state concept and two‐surface concept) are selected from numerous sand models as examples for optimization. Conventional triaxial tests on Hostun sand are selected as the objectives in the optimization. Four key points are then discussed in turn: (i) which features are necessary to be accounted for in constitutive modelling of sand; (ii) which type of tests (drained and/or undrained) should be selected for an optimal identification of parameters; (iii) what is the minimum number of tests that should be selected for parameter identification; and (iv) what is the suitable and least strain level of objective tests to obtain reliable and reasonable parameters. Finally, a useful guide, based on all comparisons, is provided at the end of the discussion. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

基于INPGA的地下水污染治理多目标优化管理模型:Ⅰ——理论方法与算例验证   总被引：1，自引：0，他引：1       下载免费PDF全文

吴剑锋  彭伟  钱家忠  吴吉春 《地质论评》2011,57(2):278-284

基于小生境技术的Pareto遗传算法(NPGA)是一种求解多目标问题的智能搜索方法,适用于优化多种非线性、不连续等复杂多目标问题.但该算法存在局部早熟收敛和收敛速度慢两个不足,在求解Pareto前沿上效果不佳.本文在NPGA的基础上,提出了改进NPGA方法(INPGA),通过Pareto解集过滤器、精英个体保留策略、邻...  相似文献   

Optimum design of stone column-improved soft soil using multiobjective optimization technique     

Kousik Deb  Anirban Dhar 《Computers and Geotechnics》2011

A combined simulation–optimization-based methodology is proposed to identify the optimal design parameters for granular bed–stone column-improved soft soil. The methodology combines a finite difference-based simulation model and an evolutionary multiobjective optimization model. A combined simulation–optimization methodology is developed for two different formulations: (a) the minimization of maximum settlement and the minimization of differential settlement subject to stress constraints; (b) the minimization of maximum settlement, the minimization of differential settlement and the maximization of the degree of consolidation subject to stress constraints. The developed methodology is applied to an illustrative system. Different scenarios are evaluated to examine critical field conditions. The solution results show that the modular ratio and the ultimate stress carrying capacity of the stone column are the most important parameters for optimal design. The obtained results also show the potential applicability of the developed methodology.  相似文献   

一种基于数据机制的DBM模型及其应用     

胡乃发  杨弘  尚尔君  王安志  金昌杰  关德新 《水文》2011,31(6):1-7

将DBM(Data Based Mechanistic)模型应用到辽东森林小流域——大湖沟,分别以其2006年6月和2007年7月数据构建研究区丰水期和枯水期的DBM模型,拟合效率系数分别为0.952 8和0.837 8,模型拟合效果在验证期的不同时段表现出明显的差异性。对丰水期模型参数用固定时间间隔法(FIS)进行时变性分析,发现参数b的取值随时间产生变化。对枯水期的二阶DBM模型进行快、慢流分解,得出了连续时间当量的快、慢流的平均滞后时间分别为5.3h和243.3h。  相似文献   

杭州黄龙饭店支腿式地下连续墙施工技术探讨          下载免费PDF全文

唐俊杰 《探矿工程》2011,38(10):46-49,45

支腿式地下连续墙在杭州地区工程中首次运用。结合实际工程实践,就支腿式地下连续墙的技术要点进行介绍,通过跟踪分析实际施工过程,简单介绍整个工艺流程和确保支腿式地下连续墙的施工质量、保证地下室开挖深度及基坑安全性、稳定性的技术措施。展望支腿式地下连续墙推广应用前景。  相似文献   

松辽地区油气勘探优快钻井技术思路          下载免费PDF全文

任杭洲  李翔 《探矿工程》2011,38(10):15-18

吉林松辽地区的腰英台、秦家屯十屋、八屋区块以及梨树断陷、长岭断陷的外围中深探井和伏龙泉浅层气井是中石化东北地区的重点区块。自勘探开发以来钻井提速面临重重困难,2010年是中原油田钻井队伍进入该市场以来的提速年,以提速为目标,大胆创新,通过大量的邻井调研分析,针对不同井的特点分别制定了不同的钻井提速措施。在成熟的钻井模式下通过不断地、连续地优化钻头选型,强化钻井参数,推广大功率高温螺杆复合钻进技术,细致的单井钻井方案优选,挖掘提速潜力,创出了有史以来最好的钻探成绩。详细介绍了松辽地区油气勘探优快钻井技术方案及具体措施。  相似文献   

新疆白干湖钨锡矿区岩心钻探施工技术     

陈昊朋  王宪忠  张志强  陈春江  王红儒  李继文  陈玉娇 《吉林地质》2011,30(1):156-157,165

随着西部大开发及国家三五八工程的开展,新疆昆仑山脉高海拔无人区成为地质找矿的重点,如何提高昆仑山脉钻孔钻探施工的效率,是当前岩心钻探施工的重点。通过白干湖钨锡矿岩心钻探的施工情况论述了该工程的施工经验和方法。  相似文献   

周期性弱凝胶调驱技术及应用     

齐陆宁  杨少春  刘芳  时丕同 《新疆地质》2011,29(3):352-355

通过室内物理模拟实验,研究平面模型中周期性注入弱凝胶效果和提高采收率机理.研究证明,弱凝胶调驱可大幅改善水驱油藏平面和纵向上的非均质性,提高水驱波及系数.周期性注入凝胶段塞能取得调剖作用和驱替效果,前段弱凝胶、中间水和后续弱凝胶可组成一个有机灵活整体,使水驱效率大幅提高,可维持调驱效果长效性.在试验基础上,针对埕岛油田北区CB6B块非均质突出,水驱矛盾突出问题,现场实施周期性弱凝胶调驱.实施后注入剖面得到明显改善,含水下降,累增油量2.05×104 t,提高采油速度0.3%.  相似文献   

新疆北山黑山岭一带多元信息综合分析与找矿靶区优选     

陈俊  郑勇  高俊宝  肖忠 《新疆地质》2011,29(4):437-441

以现代成矿理论为指导,通过GIS平台,经数据综合分析,提取新疆北山黑山岭一带地质、化探、物探、遥感和矿产等多元找矿信息,确定本区成矿要素,圈定出7个找矿靶区.采用成矿要素加权法对靶区进行优选和分类,并对优选找矿靶区进行野外验证,发现多处金、铜、钒矿点.表明在该区进行多元找矿信息综合分析与找矿靶区优选是有效的,可为新疆北...  相似文献   

页岩气含气量和页岩气地质评价综述   总被引：1，自引：0，他引：1  

李玉喜  乔德武  姜文利  张春贺 《地质通报》2011,30(203):308-317

页岩气为源岩区油气聚集,属于源岩滞留气,以游离和吸附状态为主存在。富有机质页岩含气量是页岩气资源评价和有利区优选的关键参数。页岩有机质含量和地层的压力、温度、湿度等因素影响页岩的含气量。含气量的确定方法主要有解吸和测井方法。开展页岩气地质评价,除含气量参数外,还要研究地层和构造特征、岩石和矿物成分、储层厚度和埋深、储集空间类型、储集物性、岩石力学参数、有机地球化学参数、区域现今应力场特征、流体压力、储层温度、流体饱和度、流体性质等其它参数。发展有效的系统集成方法,综合分析、评价页岩气资源潜力和预测有利区,目前也在不断探索之中。  相似文献