Showing papers on "Earthquake resistant structures published in 1986"

Disposable knee bracing: improvement in seismic design of steel frames

Abstract: A new and practical technique of lateral bracing for single and multistory steel frame construction is presented and discussed. Disposable Knee Bracing DKB technique, as it is called in this paper,...

Earthquake-resistant design of double-angle bracings

Abstract: Research is reported which evaluated current earthquake resistant design methods for double angle bracings, and developed modified procedures in order to ensure adequate seismic performance of such members. This paper summarizes the most significant findings of the research from a design perspective. Three design examples are included to illustrate step-by-step use of the recommended procedures for earthquake resistant design. The details are given of test specimens, mode of buckling and effective length factor, plastic hinges, buckling load, and local buckling. Stitches and stitch spacing is discussed as well as design forces for end connections, connection of angles to gusset plate, and the gusset plate itself.

Earthquake Design Compared to Measured Response

Abstract: The design of a full‐scale reinforced concrete building is compared to US seismic resistant design practice, and the observed behavior and measured response of the building during a series of simulated earthquake tests is compared to behavior predicted by US engineers. The test structure is the seven story building tested in Japan as part of the US‐Japan cooperative research agreement. Two west coast design offices were asked to answer five questions, which were intended to give a comparison between the design of the test structure and the design provisions of the Uniform Building Code. The results indicate that the test structure had some significant code violations with respect to detailing and strength of the shear wall. A five part questionnaire was also developed and presented to several US engineers. They were asked what type of response they expected from the test structure during simulated earthquake tests. The responses from the engineers often varied widely, but the average of their responses us...

Building on water

Abstract: Changing materials, analysis techniques and designs have yielded a new generation of concrete marine structures. The design and construction is described of a new container terminal at the Port of Oakland, which will have a reinforced concrete flat plate deck on vertical piles with no batter piles. To resist lateral loads caused by seismic forces, the back row of piles will be stronger than if they had to support gravity loads alone. Another design appropriate for seismic resistant marine structures, non-linear finite element analysis, is also described. Another new concrete design is the prestressed concrete pile. These piles when properly designed with high strength concrete and heavy confinement steel, can provide high levels of energy capacity to the berthing ships. Innovative materials that have contributed to the new generation of marine concrete structures are noted.

Evaluation of energy absorption characteristics of highway bridges under seismic conditions. volume i. final report

Abstract: Modern seismic design provisions for highway bridges rely on the energy-absorption capabilities of the ductile components and the ability of the overall system to dynamically respond so the ductile components can absorb energy. In the absence of physical data on the dynamic response of highway bridges, obtained either by physical tests or from actual earthquakes, bridge engineers must resort to analytical means to assess the dynamic response characteristics of bridges. Analytical procedures, which are developed herein for evaluating the energy-absorption characteristics of highway bridges, are incorporated into a new version (NEABS-II) of the computer program NEABS (Nonlinear Earthquake Analysis of Bridge Systems). A nonlinear beam-column element is developed for reinforced concrete bridge columns that has kinematic hardening, which permits the yield surface to translate in a force-space without changing size or shape. A gapped tension-compression, tie-bar element having bilinear force-displacement relationships was developed for the NEABS-II nonlinear expansion-joint element. Case studies are conducted with NEABS-II on three actual bridges having distinctly different dynamic response and energy-absorbing characteristics.

Evaluation of energy absorption characteristics of highway bridges under seismic conditions. volume ii. appendices

Abstract: Modern seismic design provisions for highway bridges rely on the energy-absorption capabilities of the ductile components and the ability of the overall system to dynamically respond so the ductile components can absorb energy. In the absence of physical data on the dynamic response of highway bridges, obtained either by physical tests or from actual earthquakes, bridge engineers must resort to analytical means to assess the dynamic response characteristics of bridges. Analytical procedures, which are developed herein for evaluating the energy-absorption characteristics of highway bridges, are incorporated into a new version (NEABS-II) of the computer program NEABS (Nonlinear Earthquake Analysis of Bridge Systems). A nonlinear beam-column element is developed for reinforced concrete bridge columns that has kinematic hardening, which permits the yield surface to translate in a force-space without changing size or shape. A gapped tension-compression, tie-bar element having bilinear force-displacement relationships was developed for the NEABS-II nonlinear expansion-joint element. Case studies are conducted with NEABS-II on three actual bridges having distinctly different dynamic response and energy-absorbing characteristics.