Collaborative Research: An Innovative Gap Damper to Control Seismic Isolator Displacements in Extreme Earthquakes
The main objective of this project is to develop and test a phased damping device, or "gap damper," to act alongside a base isolation system for buildings or bridges.
This project focuses developing more resilient buildings through the use of self-centering structural systems. This project seeks to better understand the interaction between rocking walls and floor systems through large-scale testing.
The curved bridge project tested nine different configurations to investigate the seismic effects of multi-span curved bridges using a 2/5 scale model of a three-span bridge.
This project integrates multidisciplinary system-level studies to develop a novel simulation capability and implementation process for enhancing the seismic performance of the ceiling-piping-partition system.
The objectives of this project are to develop a fundamental knowledge of the impact of combined actions on column performance and system response and to establish analysis and design procedures that include the impact at both the component and system levels.
The objective of this research project was to determine the capacity of clay plastered, load bearing, straw bale wall assemblies under in-plane cyclic loading, and the performance of a small full-scale straw bale house using shake table simulation.
This study addressed two important aspects of bridge seismic response, both focused on system performance: (1) behavior of modern concrete bridges reinforced with conventional materials, and (2) development and evaluation of bridges with innovative materials and details.
This is a component of a multi-university project that involves large-scale bridge system and component testing, centrifuge testing, and field investigation of soil-foundation-structure-interaction effects.
This research investigates a new methodology for post-event structural damage assessment, using wireless sensors.
This study tested a 3-column prestressed bridge bent to study the seismic performance of pile to pile-cap connections.
This project investigates the seismic response of rigid connections between precast columns and footing. Five half-scale column models will be tested by reversed cyclic loading.
Under moderate and strong earthquakes, it is essential for bridge columns to dissipate energy through nonlinear deformations in plastic hinges. Existing details for precast segmental columns offer minimal energy dissipation as a result of the discontinuity of longitudinal reinforcement; therefore, precast members are not used in high seismic zones. The purpose of the study is to develop precast columns that are able to dissipate energy under cyclic loading.
This project subjected three one-third scale single columns to Sylmar earthquake with gradually increasing PGA using one of the shake tables at the University of Nevada, Reno and the mass-rig setup. After each test, the column was repaired rapidly, using CFRP wrapping, and retested to evaluate the emergency repair performance.
The objectives of this experiment are to find the strength, stiffness and failure modes due to transverse cyclic displacement in end cross frames.
An experimental and analytical study of pipe-pin hinges included comprehensive analytical modeling and experimental study on the subcomponents of the detail, the development of a design method and proposed improvements for the existing pipe-pin detail.
Although slab bridges are common type of bridge, the current version of the Bridge Design Specification (BDS) and the Seismic Design Criteria (SDC) provide limited design guidance for pile extension connection details for slab bridges. Slab-bridge connections have not been tested, and this project tests eight large-scale column-slab bridge connections.
The main research objective is to investigate the seismic performance of two-column bridge bents with different aspect ratios using current Caltrans design criteria.
In-fill wall retrofit has been used in many multi-column bridge bents in California and elsewhere. Some of the in-fill walls are connected to the cap beam while others are stopped short of the bottom of cap beam with a 6-in. gap to facilitate construction.
The focus of the present study is on the walls with a gap at the top, and the objective is to study the lateral load path.