Terrestrial laser scanning (TLS) provides a rapid, remote sensing technique to model 3D objects. Previous work applying TLS to structural analysis has demonstrated its effectiveness in capturing simple beam deflections and modeling existing structures. This paper extends TLS to the application of damage detection and volumetric change analysis for a full-scale structural test specimen. Importantly, it provides a framework necessary for such applications, in combination with an analysis approach that does not require tedious development of complex surfaces. Intuitive slicing analysis methods are presented, which can be automated for rapid generation of results. In comparison with conventional photographic and surface analysis methods, the proposed approach proved consistent. Furthermore, the TLS data provided additional insight into geometric change not apparent using conventional methods. As with any digital record, a key benefit to the proposed approach is the resulting virtual test specimen, which is av...

On 4 September 2010, a magnitude Mw 7.1 earthquake struck the Canterbury region on the South Island of New Zealand. The epicentre of the earthquake was located in the Darfield area about 40 km west of the city of Christchurch. Extensive damage was inflicted to lifelines and residential houses due to widespread liquefaction and lateral spreading in areas close to major streams, rivers and wetlands throughout Christchurch and Kaiapoi. Unreinforced masonry buildings also suffered extensive damage throughout the region. Despite the severe damage to infrastructure and residential houses, fortunately, no deaths occurred and only two injuries were reported in this earthquake. From an engineering viewpoint, one may argue that the most significant aspects of the 2010 Darfield Earthquake were geotechnical in nature, with liquefaction and lateral spreading being the principal culprits for the inflicted damage. Following the earthquake, an intensive geotechnical reconnaissance was conducted to capture evidence and perishable data from this event. The surveys were performed on foot, by car and from a helicopter over a period of six days. A broad-brush field reconnaissance was conducted in the first two days, followed by pin-point investigations at specific locations including detailed site inspections and field testing using: Dynamic Cone Penetration Test (DCPT), Swedish Weight Sounding (SWS), and Spectral Analysis of Surface Waves (SASW). This paper summarizes the observations and preliminary findings from this early reconnaissance work.

A landmark experimental program was conducted to advance the understanding of nonstructural system performance during earthquakes. The centerpiece of this effort involved shake table testing a full‐scale five‐story reinforced concrete building furnished with a broad variety of nonstructural components and systems (NCSs) including complete and operable egress, mechanical and electrical systems, facades, and architectural layouts. The building‐NCS system was subjected to a suite of earthquake motions of increasing intensity, while base‐isolated and then fixed at its base. In this paper, the major components of the test specimen, including the structure and its NCSs, the monitoring systems, and the seismic test protocol are described in detail. Important response and damage characteristics of the structure are also presented. A companion paper describes the damage observed for the various NCSs and correlates these observations with the structure's response.

Practical guidelines for characterization of soil‐structure interaction (SSI) effects for shallow foundations are typically based on representing foundation‐soil interaction in terms of viscoelastic impedance functions that describe stiffness and damping characteristics. Relatively advanced tools can describe nonlinear soil‐foundation behavior, including temporary gap formation, foundation settlement and sliding, and hysteretic energy dissipation. We review two tools that describe such effects for shallow foundations and that are implemented in the computational platform OpenSees: a beam‐on‐nonlinear‐Winkler foundation (BNWF) model and a contact interface model (CIM). We review input parameters and recommend parameter selection protocols. Model performance with the recommended protocols is evaluated through model‐to‐model comparisons for a hypothetical shear wall building resting on clay and model‐data comparisons for several centrifuge test specimens on sand. The models describe generally consistent moment‐rotation behavior, although shear‐sliding and settlement behaviors deviate depending on the degree of foundation uplift. Pronounced uplift couples the moment and shear responses, often resulting in significant shear sliding and settlements. Such effects can be mitigated through the lateral connection of foundation elements with tie beams.

The nonlinear behavior of shallow foundations under large amplitude earthquake‐induced loading can result in dissipation of seismic energy through the mechanism of soil yielding beneath the foundation. In addition, foundation uplifting may shift the period of the soil‐foundation‐structure system away from the damaging energy content of most earthquakes. However, this yielding and uplifting may lead to excessive transient and permanent deformations (settlement, rocking, and sliding). Therefore, modeling procedures that account for foundation nonlinearity and uplift are needed before these benefits can be realized in performance based earthquake engineering (PBEE) practice. This paper adopts a beam‐on‐nonlinear‐Winkler‐foundation (BNWF) simulation methodology for modeling shallow foundation‐structure systems, where seismically‐induced rocking plays a predominant role in their response. Numerical results demonstrate that reasonable comparison between the nonlinear Winkler‐based approach, and experimental response in terms of moment‐rotation, settlement‐rotation, and shear‐sliding displacement can be obtained, given an appropriate selection of model and soil properties.