NEESR: Performance Based Seismic Design of Geomembrane Liner Systems for Waste Containment

该奖项将为工程师提供改进的能力，以确定现代土工膜衬垫废物遏制系统在遭受强烈地震时是否能保持其完整性。目前评估废物围护系统承受地震载荷能力的做法采用经验性能指标，而不是直接计算土工膜衬垫上的载荷（应力和应变）。该合同将使用离心机模型测试来评估直接计算衬垫应力和应变所必需的输入参数，并验证用于评估这些应力和应变的数值模型。该模型的验证将包括验证由于接缝、补丁和锚沟引起的应力（或应变）浓度对衬砌性能的影响。该项目的数据将存档，并通过NEES项目仓库/数据存储库（http://www.nees.org）.This)向公众提供，该奖项为废物密封系统的抗震设计提供了新的范例。将目前土工膜衬垫系统抗震设计的工程实践从依赖于不可靠的性能指标的经验过程转变为直接评估土工膜上的地震荷载的基于性能的抗震设计过程。该项目还可能对填埋衬垫施工质量保证（CQA）实践产生变革性影响，因为土工膜中接缝、补丁和锚沟的应变集中系数的实验验证应该导致新的指导方针，即在哪里切割缝样进行CQA测试（例如，永远不要在斜坡顶部或锚沟附近），以及此类测试的频率。通过促进更合理的基于性能的抗震设计和CQA，该项目应加强环境保护，并促进开发更有效的设计和施工方法，以应对地震荷载下的废物围护系统。该奖项是国家减少地震灾害计划（NEHRP）的一部分。

This award will provide engineers with an improved ability to determine whether or not a modern geomembrane liner waste containment system can maintain its integrity when subjected to a strong earthquake. Current practice for evaluating the ability of waste containment systems to withstand earthquake loading employs an empirical index of performance rather than direct calculation of the loads (stresses and strains) on the geomembrane liner. This award will use centrifuge model testing to evaluate input parameters essential to direct calculation of liner stresses and strains and to validate a numerical model to evaluate these stresses and strains. Validation of the model will include validation of the influence of stress (or strain) concentrations due to seams, patches, and anchor trenches on liner performance. Data from this project will be archived and made available to the public through the NEES Project Warehouse/data repository (http://www.nees.org).This award offers the promise of a new paradigm for seismic design of waste containment systems, transforming current engineering practice for geomembrane liner system seismic design from an empirical process that depends upon an unreliable index of performance to a performance-based seismic design procedure in which the seismic loads on the geomembrane are directly evaluated. The project may also have a transformative impact on landfill liner construction quality assurance (CQA) practices, as experimental verification of strain concentration factors for seams, patches, and anchor trenches in geomembranes should lead to new guidelines on where it is appropriate to cut seam samples for CQA testing (e.g. never at the top of a slope or near an anchor trench) and perhaps on the frequency of such testing. By facilitating more rational performance-based seismic design and CQA, the project should enhance environmental protection and facilitate the development of more effective design and construction practices for waste containment systems subject to earthquake loading. This award is part of the National Earthquake Hazards Reduction Program (NEHRP).