RAPID/Collaborative Research: Investigation of the Effects of Rockfall Impacts on Structures During the Christchurch Earthquake Series

该奖项资助美国和新西兰的合作研究，该研究将调查地震引起的落石对住宅和小型商业建筑的影响。 2010-2011 年新西兰坎特伯雷地震序列包括四次大地震，在基督城大都市区产生了强烈的地面震动。 这些地震引发了数千起落石，影响了数百座建筑物，并造成了人员和资金损失。 然而，这些落石对结构的影响差异很大。 在某些情况下，巨石会陷入建筑物的结构系统中，造成损坏，但会保护生命安全。 在其他情况下，巨石完全穿透建筑系统并导致结构倒塌。 虽然落石与建筑系统的相互作用在概念上可以理解为冲击能量和结构能力的函数，但仍然不清楚这些因素如何控制建筑物对这些冲击的抵抗力。 工程文献中几乎没有这方面的信息。 这项工作将是对该主题的第一个广泛且有据可查的研究，并将立即为世界上落石构成潜在威胁的所有地区的工程师提供帮助。 为此，本研究旨在获取、处理和存档有关落石对一系列常见住宅和商业结构的影响的数据。 这项研究将通过对大约 30 座受损建筑物进行地理参考、3D、地面激光雷达扫描和运动结构 (SfM) 摄影采集来完成。 除了详细的记录之外，生成的数据库还将大幅增加落石与结构相互作用的高质量案例历史的数量。 这项工作还旨在通过落石过程的一系列初步耦合跳动/结构影响模型模拟来确定控制各种常见结构弹性的因素。 该项目包括一系列更广泛的影响，其中最引人注目的是制定关于建设系统抵御落石的能力的初步准则。 这些指南将对全世界的建筑规范产生重要影响，并且将更直接地为基督城当地的重建和恢复工作提供信息。这项工作将与新西兰 GNS Science 的研究人员密切合作完成。

This award funds collaborative U.S. - New Zealand research that will investigate the effects of earthquake-induced rockfalls on residential and small commercial structures. The 2010-2011 Canterbury, New Zealand Earthquake Sequence included four major earthquakes that produced high levels of ground shaking in the Christchurch metropolitan region. These earthquakes triggered thousands of rockfalls, which impacted several hundred buildings and resulted in both human and capital losses. However, the impact of these rockfalls on structures varied widely. In some instances boulders became enmeshed within a building's structural system, causing damage but preserving life-safety. In other situations boulders fully penetrated building systems and caused structural collapse. While a rockfall's interaction with a building system may be conceptually understood to be a function of both impact energy and structural capacity, it still remains unclear exactly how these factors govern a building's resistance to these impacts. There is virtually no information on this in the engineering literature. This work will be the first extensive, well-documented study of the subject and will be of immediate use to engineers in all parts of the world where rockfalls are a potential threat. To this end, this research seeks to acquire, process, and archive data pertaining to the impact of rockfalls on a series of common residential and commercial structures. This study will be accomplished through geo-referenced, 3D, ground-based LIDAR scans and Structure from Motion (SfM) photographic acquisition at approximately 30 damaged buildings. In addition to documentation at high detail, the resulting database will provide a substantial increase in the number of high-quality case histories of rockfall-structure interaction. This work additionally aims to identify the factors that govern the resilience of a wide range of common structures through a preliminary series of coupled runout/structural impact model simulations of the rockfall process. The project includes a range of broader impacts including most notably development of preliminary guidelines on building system resilience to rockfalls. These guidelines will have important implications for building codes worldwide and more immediately will serve to inform local rebuilding and recovery efforts in Christchurch. The work will be done in close cooperation with researchers from GNS Science, New Zealand.