A research study has been conducted to simulate liquefaction in saturated sandy soil induced by nearby controlled blasts. The purpose of the study is to help quantify soil characteristics under multiple and consecutive high-magnitude shock environments similar to those produced by large earthquakes.; The simulation procedure involved the modeling of a three-dimensional half-space soil region with pre-defined, embedded, and strategically located explosive charges to be detonated at specific time intervals. LS-DYNA, a commercially available finite element hydrocode, was the solver used to simulate the event. A new geo-material model developed under the direction of the U.S. Federal Highway Administration was applied to evaluate the liquefaction potential of saturated sandy soil subjected to sequential blast environments. Additional procedural enhancements were integrated into the analysis process to represent volumetric effects of the saturated soil's transition from solid to liquid during the liquefaction process. Explosive charge detonation and pressure development characteristics were modeled using proven and accepted modeling techniques.; As explosive charges were detonated in a pre-defined order, development of pore water pressure, volumetric (compressive) strains, shear strains, and particle accelerations were carefully computed and monitored using custom developed MathCad and C/C++ routines. Results of the study were compared against blast-test data gathered at the Fraser River Delta region of Vancouver, British Columbia in May of 2005 to validate and verify the modeling procedure's ability to simulate and predict blast-induced liquefaction events. Reasonable correlations between predicted and measured data were observed from the study.
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机译:已经进行了一项研究研究,以模拟附近受控爆炸引起的饱和沙土中的液化。该研究的目的是帮助量化在多次和连续的高强度冲击环境(类似于大地震所产生的环境)下的土壤特性。模拟过程包括对三维半空间土壤区域进行建模,该区域具有预定义,嵌入式和战略性定位的炸药,并在特定的时间间隔引爆。 LS-DYNA是市售的有限元液压代码,是用于模拟事件的求解器。在美国联邦公路管理局的指导下开发了一种新的土工材料模型,以评估遭受连续爆炸环境的饱和砂土的液化潜力。附加的程序增强功能已集成到分析过程中,以表示液化过程中饱和土壤从固体到液体过渡的体积效应。爆炸物的爆轰和压力发展特性是使用公认的公认的建模技术进行建模的。当炸药以预定的顺序引爆时,使用定制开发的MathCad和C / C ++例程仔细计算和监视了孔隙水压力,体积(压缩)应变,剪切应变和颗粒加速度的变化。将研究结果与2005年5月在不列颠哥伦比亚省温哥华的弗雷泽河三角洲地区收集的爆炸测试数据进行比较,以验证和验证建模程序模拟和预测爆炸诱发的液化事件的能力。从研究中观察到预测数据与测量数据之间的合理相关性。
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