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，将调查地震引起的岩崩对住宅和小型商业结构的影响。2010-2011年新西兰坎特伯雷地震序列包括四次大地震，在克赖斯特彻奇大都市区产生了强烈的地面震动。这些地震引发了数千次落石，影响了数百座建筑物，造成了人员和资本损失。然而，这些岩崩对建筑物的影响差别很大。在某些情况下，巨石会陷入建筑物的结构系统中，造成损害，但保护了生命安全。在其他情况下，巨石完全穿透建筑系统并导致结构倒塌。虽然从概念上讲，落石与建筑系统的相互作用可以理解为冲击能量和结构能力的函数，但这些因素如何影响建筑物对这些冲击的抵抗力仍然不清楚。在工程文献中几乎没有这方面的信息。这项工作将是第一次对这一主题进行广泛的、有充分文件记录的研究，对世界各地的工程师来说，落石是一个潜在的威胁。为此，本研究试图获取、处理和存档有关岩崩对一系列常见住宅和商业结构影响的数据。这项研究将通过地理参考、3D、地面激光雷达扫描和运动结构（SfM）摄影采集在大约30座受损建筑中完成。除了高度详细的记录外，由此产生的数据库将大大增加岩崩-结构相互作用的高质量历史案例的数量。这项工作的另一个目的是通过对岩崩过程的一系列耦合跳动/结构冲击模型模拟，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了关于建筑系统抗落石能力的初步指导方针。这些指导方针将对世界各地的建筑规范产生重要影响，并将更直接地为克赖斯特彻奇当地的重建和恢复工作提供信息。这项工作将与新西兰GNS科学公司的研究人员密切合作。

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.