Earthquake resistant structures

About: Earthquake resistant structures is a research topic. Over the lifetime, 1126 publications have been published within this topic receiving 27467 citations.

Control of Building Sway and Force Flows Using Ultralightweight Slabs

Abstract: Design analyses are presented to demonstrate the technical advantages of substituting ultralightweight slab materials like cross-laminated-timber (CLT) for reinforced concrete (RC) floors and roofs of low-rise and high-rise hybrid building superstructures. Such substitution reduces the gravitational masses of slab by at least two-thirds without reducing functionality as bending or diaphragm slabs. Specific illustrations of design impacts of using CLT are given for hybrid building superstructures where steel or RC frameworks are the primary means of resisting effects of gravity forces associated with occupied built spaces. Results shown apply to two-story buildings in which effects of lateral forces associated with wind or seismic loads are resisted entirely by a steel moment framework, and six- and twenty four–story buildings in which RC shear walls within building cores primarily resist effects of such lateral loads. Consideration is also given to how fire engineering design decisions can impact ...

High-Performance Composite-Reinforced Earthquake Resistant Buildings with Self-Aligning Capabilities

Abstract: This paper describes the experimental procedures and presents preliminary results of the international project entitled “High- Performance Composite-Reinforced Earthquake Resistant Buildings with Self-Aligning Capabilities”. The goal of the project was to increase our understanding of the seismic performance of woodlaminated frames with locally reinforced members. Two sets of experiments were performed. First, a full-scale one-story frame with relatively rigid connections was tested on a shaking table, Kasal et al. (J Perform Constr Fac, 2013). To achieve a stiff connection, hardwood blocks and self-tapping screws 120–250 mm long were used to facilitate the connection between beams and columns. Next, a scaled three-story frame was tested. Highly stressed regions of beams and columns of the second frame were reinforced with glass fiber (GF) sheets to mitigate potential brittle failure in anticipated weak zones. Frictional connections between beams and columns permitted a control of the magnitude of dissipated energy in the system. The connections were expected to behave stiffly under small excitations, dissipate energy through friction during moderate seismic excitation, and degrade at higher seismic loads. While the friction can be relatively well predicted, the degradation of the connection cannot, due to the uncertainty in properties of wood.

Studies on Seismic Isolation of Buildings

Abstract: This paper has studied the applicability of base isolation to structures. The Navy is evaluating the potential use of base isolation for essential structures that must remain functional in a postearthquake environment. The paper reviews preliminary building‐selection criteria and structural design criteria. For low‐rise regular‐frame construction situated on a rock or stiff site and housing‐sensitive equipment, base isolation of the columns offers the potential for significant damage reduction. The paper presents a comparison of analysis techniques treating the isolator as a nonlinear hysteretic element and as linear elements with and without nodal damping. The results indicate that for the case studied, significant differences in displacement and drift result while moments vary by about 10%. Vertical acceleration effects were found to cause an increase in maximum moment by about 15%.

Seismic protection of bridges

Abstract: During the past 2 decades, bridge engineers have gained a better understanding of the behavior of structures during an earthquake The ductility-design philosophy is the mainframe of modern seismic-design guidelines in the United States and most countries abroad While this design philosophy provides safety against collapse, it tends to be costly because of the damage induced in plastic-hinge zones and to the severe lateral displacements that can occur even in a moderate earthquake Therefore, in recent years, design engineers have sought an alternative design philosophy that avoids or limits damage to a bridge to maintain postearthquake serviceability Seismic isolation has emerged as one of the most promising retrofitting strategies for improving the seismic performance of existing bridges It is also an attractive approach for new construction when conventional design is not suitable or economical In January 1994, the Federal Highway Administration, California Department of Transportation, and the Highway Innovative Technology Evaluation Center cooperated in launching a full-scale, dynamic testing and evaluation program of readily available seismic isolation and energy dissipation systems A total of 11 domestic and international manufacturers completed the testing program The program is expected to increase the confidence level of bridge owners and lead them to consider and use isolation/damping technology cost-effectively to protect otherwise vulnerable structures from more severe earthquake damage In addition, it will provide useful data to academic researchers