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Failure analysis of RC shear walls with staggered openings under seismic loads تحلیل گسیختگی دیوارهای برشی بتن مسلح با بازشوهای شطرنجی در بارهای لرزه ای Marius Mosoarca a b s t r a c t Reinforced concrete shear walls are used to design buildings located in seismic areas, because of their rigidity, bearing capacity and high ductility. Until now many theoretical and experimental tests on shear walls with or without openings have been made, therefore their failure modes have been analysed and are rather very well-known; the research results being confirmed by real failure modes of RC walls after earthquakes. Design codes and standards based on the knowledge of the failure modes of the reinforced concrete walls were developed in order to obtain the ductile failure mechanisms. A special case is the failure mode of the reinforced concrete shear walls with vertical staggered openings. If at coupled walls the elements must be designed so that the plastic hinges appear at the ends of the coupled beams and then in the pier, this thing is more difficult at shear walls with staggered openings. Theoretical and experimental studies on structural walls with staggered openings, lamellar walls and walls with bulbs at the end have been made recently. There have also been studied the followings: the degradation of the stiffness, the ductility function to the intensity of the seismic force, the presence of the vertical forces, the position and the size of the openings and the reinforcing ways. The article presents the results of the theoretical and experimental tests on failure modes of three types of reinforced concrete shear walls with staggered openings which are compared to those obtained from walls with vertical ordered openings as far as the seismic response is concerned. The failure modes of the structural walls under seismic stress have been identified using calculus programs and cyclic alternated experimental tests. The theoretical research on the failure modes was the basis for the elaboration of a simplified methodology for the calculus of the maximum theoretical seismic force that produces the concrete crushing in the ultimate limit stage. The results theoretically obtained with the help of the calculus programs have been confirmed experimentally. The analysis of the failure modes, obtained with the computing methodology proposed, contributed to the completion of the seismic design codes for shear walls with staggered openings. منبع عملکرد_دیوارهای_برشی_بتنی_با_بازشوهای.pdf
HAZUS Earthquake Loss Estimation Methods Charles A. Kircher1; Robert V. Whitman2; and William T. Holmes3 Abstract: This paper provides background and historical perspective on the development of the earthquake loss estimation methods of the HAZUS technology referred to as HAZUS Earthquake, describes the various modules of HAZUS Earthquake, and summarizes the key concepts of these methods. HAZUS Earthquake modules calculate seismic hazard, evaluate the likelihood of various states of damage to buildings, lifelines, and other components of the built environment, and estimate both direct and indirect losses resulting from this damage. The focus of this paper is on building-related methods. The paper also describes two recent improvements to the HAZUS Earthquake technology: 1 the Advanced Engineering Building Module AEBM and 2 use of ShakeMap ground motion data. The AEBM allows expert users to develop “building-specific” damage and loss functions. ShakeMap ground motion data HAZUS may be used to rapidly assess potential damage and loss immediately following an earthquake. The paper closes with a comparison of damage and loss estimated using ShakeMap data with actual damage and loss due to the 1994 Northridge earthquake. DOI: 10.1061/ASCE1527-698820067:245 CE Database subject headings: Earthquakes; Seismic effects; Damage; Estimation; Models. منبع دانلود از پیوست kircher2006.pdf
Earthquake-induced displacements of gravity retaining walls and anchor-reinforced slopes Aurelian C. Trandafir a,, Toshitaka Kamai b, Roy C. Sidle c a Department of Geology and Geophysics, University of Utah, 135 South 1460 East Rm 717, Salt Lake City, UT 84112-0111, USA b Research Centre on Landslides, Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji, 611-0011 Kyoto, Japan c Slope Conservation Section, Geohazards Division, Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji, 611-0011 Kyoto, Japan a r t i c l e i n f o Article history: Received 20 October 2005 Received in revised form 17 April 2008 Accepted 21 April 2008 Keywords: Earthquakes Slopes Gravity retaining walls Anchors Seismic displacements a b s t r a c t This paper examines in terms of seismic performance, the effectiveness of anchor reinforcement against gravity retaining walls used to stabilize a dry homogenous fill slope in earthquake-prone environment. Both analyzed stabilizing measures have the same design yield acceleration estimated from a limit equilibrium approach. The earthquake-induced displacements are calculated using a sliding block formulation of the equation of motion. Sliding failure along the base of the gravity retaining wall and rotational failure of the soil active wedge behind the wall, as well as rotational failure of the slide mass of the anchor-reinforced slope were considered in the present formulation. For the specific characteristics of the analyzed fill slope and input horizontal ground motion, the slope reinforced with anchors appears to experience vertical and horizontal seismic displacements at slope crest smaller by 12% and respectively, 32% than the vertical and horizontal earthquake-induced deformations estimated at the top of the active wedge behind the gravity retaining wall. فرستنده : مهندس مهران سلطانی نژاد Earthquake-induced-displacements.pdf