Representative research projects
- Straw bale house: 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.
- 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.
- Unbonded post-tensioned rocking walls for seismic resilient structure: This project focuses on 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.
- Curved bridge project: 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.
- 4-span bridge: 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.
- Aspect ratio: The main research objective is to investigate the seismic performance of two-column bridge bents with different aspect ratios using current Caltrans design criteria.
- Precast bridge columns: 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.
- 2-span bridge: 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.
- Pile-cap connections: This study tested a 3-column prestressed bridge bent to study the seismic performance of pile to pile-cap connections.
- Emergency bridge repair: This project subjected three one-third scale single columns to Sylmar earthquake with gradually increasing PGA. After each test, the column was repaired rapidly, using CFRP wrapping, and retested to evaluate the emergency repair performance.
- Nonstructural Grand Challenge: 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.
- Next-generation bridge components: 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.
- Wireless monitoring: This research investigates a new methodology for post-event structural damage assessment, using wireless sensors.
- Telescopic pipe-pin: 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.
- Slab bridge: 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.
- CABER: This project aims to develop 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.
- In-fill wall retrofit: In-fill wall retrofit has been used in many multi-column bridge bents in California and elsewhere. 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.
- Three girder bridge: The objectives of this experiment are to find the strength, stiffness and failure modes due to transverse cyclic displacement in end cross frames.