RAPID: Geotechnical-driven Damage Patterns and Liquefaction in the January 2010 Haiti Earthquake

该快速反应研究(RAPID)奖提供资金，使调查人员能够通过对海地地震影响的更多和更深入的调查来加强先前有限范围的DCPT和VS调查。2010年1月12日海地发生7.0级地震，对建筑和自然环境造成巨大破坏，摧毁建筑物，使太子港海港瘫痪，并造成大型海岸、公路和斜坡坍塌。作为地球工程极端事件侦察小组的一部分，PI参加了一次海地的侦察之旅。该研究小组在http://www.geerassociation.org/GEER_Post%20EQ%20Reports/Haiti_2010/Cover_Haiti10.html.上发表了初步发现。该团队从最初的侦察中带回了一组广泛的数据，包括几个地点的剪切波速(Vs)和动态触探试验(DCPT)数据。然而，在初步损失评估和初步调查结果评估之后，确定了一些需要进一步调查的关键细节。鉴于这次地震造成的巨大破坏，专业人士必须最大限度地从这次事件中吸取教训，以便在未来海地、其他发展中沿海国家和世界其他地方发生地震时将损失降至最低。这项活动的学术价值有三个方面。(1)该小组将通过更多和更深入的调查以及土壤采样和实验室测试来加强以前有限范围的DCPT和VS调查，以了解碳酸盐砂中的液化，因为尽管这些砂在世界各地都存在，但在全球液化案例历史数据库中的代表性很低。这项工作将主要涉及在太子湾南部海岸，主要是Leogane和Petit Goave之间，以及太子港以北的主要河流进行采样和测试。随后的实验室测试将包括环形剪切和循环三轴测试。(2)该小组将扩大对太子港周围社区(如Petion-Ville)山坡和斜坡上潜在地形影响破坏模式的初步观察。这项工作将包括收集斜坡走向和倾角，接近山脊顶部，并在确定了明显受地形影响的明显破坏模式的地区进行浅层VS测量。(3)该小组将在太子港低洼地区收集15至20个近地表VS剖面，在那里观察到潜在的软土放大效应，导致明显的破坏模式。这些测量值将在空间上分布在遭受严重破坏和遭受轻微破坏的地区。这些工作将利用创新的3D成像软件和校准的数码相机来加强，以开发这些地点受损的3D数字高程模型。该项目更广泛的影响集中在培训学生和改善工程学的实践状态。每个小组成员将带来一名研究生，培训他们进行侦察，并鼓励他们举办研讨会，介绍他们的经验，小组将与海地矿产和自然资源部的人员进行互动。此外，该小组还将发表关于碳酸盐砂土液化、地形影响和场地影响的研究结果。评估地球物理数据和在选定地点回收的样本的实验室测试还将包括培训研究生和本科生。该奖项由美国国家科学基金会国际科学与工程办公室(OISE)共同资助。

This Rapid Response Research (RAPID)award provides funding to allow the investigators to augment previous, limited-scope DCPT and Vs investigations with additional and deeper investigations into the effects of the Haiti earthquake.The magnitude 7.0 earthquake that struck Haiti on January 12, 2010 caused tremendous damage to the built and natural environment, destroying buildings, crippling the Port-au-Prince seaport, and causing large coastal, roadway, and slope failures. The PIs participated in a reconnaissance trip to Haiti as part of a Geo-engineering Extreme Event Reconnaissance team. The team published preliminary findings at: http://www.geerassociation.org/GEER_Post%20EQ%20Reports/Haiti_2010/Cover_Haiti10.html. The team brought back an extensive set of data from this initial reconnaissance, including shear wave velocity (Vs) and dynamic cone penetration test (DCPT) data at several sites. However, after an initial damage assessment and an evaluation of preliminary findings, a number of critical details that require further investigation have been identified. Given the tremendous damage that resulted from this earthquake, it is imperative that the profession maximize what is learned from this event in order to minimize damage during future earthquakes in Haiti, in other developing coastal nations, and elsewhere around the world.The intellectual merit of this activity is threefold. (1) The team will augment previous, limited-scope DCPT and Vs investigations with additional and deeper investigations, as well as soil sampling and lab testing to understand liquefaction in carbonate sands, as these sands are poorly represented in the worldwide liquefaction case history database despite their worldwide presence. This work will chiefly involve sampling and testing along the southern coast of Port au Prince Bay, primarily between Leogane and Petit Goave, and along the major rivers north of Port au Prince. Subsequent lab testing will include ring shear and cyclic triaxial testing. (2) The team will expand initial observations of potential topographic effects on damage patterns on the hillsides and slopes in communities surrounding Port-au-Prince, such as Petion-Ville. This effort will involve collecting slope strike and dip angles, proximity to ridge tops, and obtaining shallow Vs measurements in areas identified with noticeable damage patterns apparently influenced by topography. (3) The team will collect 15 to 20 near-surface Vs profiles in low-lying areas of Port-au-Prince where potential soft-soil amplification effects leading to noticeable damage patterns are observed. These measurements will be spatially-distributed in both areas that suffered heavy damage and areas that suffered minimal damage. These efforts will be enhanced using innovative 3D imaging software and calibrated digital cameras to develop 3D digital elevation models of damage at these sites. The broader impacts of this project are focused on training students and improving the state-of-practice of engineering. Each team member will bring one graduate student to train them to perform reconnaissance and will encourage them deliver seminars about their experiences and the team will interact with personnel from Ministry of Mines and Natural Resources in Haiti. Additionally, the team will publish findings on liquefaction of carbonate sands, topographic effects, and site effects. Evaluating geophysical data and laboratory testing of samples recovered at select sites will also involve training graduate and undergraduate students.This award is co-funded by the NSF Office of International Science and Engineering (OISE).