Approximate Analysis for Shear Force Amplification Effect in Ordinary RC Shear Walls

Reinforced concrete frame-shear wall structure is a double resistance to lateral force system, in which the frames and shear walls work cooperatively and the distributive rule of the earthquake force varies with different earthquake actions. To ensure the frames bear the increasing earthquake shear force and play a role of second defense line due to the internal force re-distribution after the stiffness degradation of shear walls, the elastic design earthquake shear force of the frames should be adjusted. However the adjustment measures applied in Chinese code are proposed according to the design experiences of engineers and lack of the theoretical and computational analytical basis. Moreover, there is a dispute about ignoring the rule of the shear force redistribution along storey or not, it is necessary to further evaluate the rationality of the measures in the code. In this paper, based on a 3-D precise nonlinear frame-shear wall structure analysis model, the re-distributive rule of the internal force under strong earthquake was studied and the adjustment measures of earthquake force in the frames were checked. Finally, some design suggestions were proposed.

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EVALUATION OF LOADING RIGHT-ANGLED DIRECTION SHEAR FORCE IN COLUMNS INDUCED BY L-SHAPED SHEAR WALLS IN R/C BUILDING

Journal of Structural and Construction Engineering (Transactions of AIJ) ◽

10.3130/aijs.69.93_2 ◽

2004 ◽

Vol 69 (580) ◽

pp. 93-98

Author(s):

Hirohisa KITAYAMA ◽

Ichiro SHIRAISHI

Keyword(s):

Shear Force ◽

Shear Walls

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Seismic Fragility of Ordinary Reinforced Concrete Shear Walls with Coupling Beams Designed Using a Performance-Based Procedure

Applied Sciences ◽

10.3390/app10124075 ◽

2020 ◽

Vol 10 (12) ◽

pp. 4075

Author(s):

Seong-Ha Jeon ◽

Ji-Hun Park

Keyword(s):

Reinforced Concrete ◽

Dynamic Analysis ◽

Seismic Design ◽

Nonlinear Dynamic ◽

Shear Force ◽

Nonlinear Dynamic Analysis ◽

Shear Walls ◽

Analytical Models ◽

High Rise ◽

Collapse Probability

The seismic performance of ordinary reinforced concrete shear walls, that are commonly used in high-rise residential buildings in Korea (h < 60 m), but are prohibited for tall buildings (h ≥ 60 m), is evaluated in this research project within the framework of collapse probability. Three bidimensional analytical models comprised of both coupled and uncoupled shear walls exceeding 60 m in height were designed using nonlinear dynamic analysis in accordance with Korean performance-based seismic design guidelines. Seismic design based on nonlinear dynamic analysis was performed using different shear force amplification factors in order to determine an appropriate factor. Then, an incremental dynamic analysis was performed to evaluate collapse fragility in accordance with the (Federal Emergency Management Agency) FEMA P695 procedure. Four engineering demand parameters including inter-story drift, plastic hinge rotation angle, concrete compressive strain and shear force were introduced to investigate the collapse probability of the designed analytical models. For all analytical models, flexural failure was the primary failure mode but shear force amplification factors played an important role in order to meet the requirement on collapse probability. High-rise ordinary reinforced concrete shear walls designed using seven pairs of ground motion components and a shear force amplification factor ≥ 1.2 were adequate to satisfy the criteria on collapse probability and the collapse margin ratio prescribed in FEMA P695.

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Seismic demand of moderately ductile reinforced concrete shear walls subjected to high-frequency ground motions

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2013-0073 ◽

2014 ◽

Vol 41 (2) ◽

pp. 125-135 ◽

Cited By ~ 7

Author(s):

Hieu Luu ◽

Pierre Léger ◽

Robert Tremblay

Keyword(s):

Reinforced Concrete ◽

High Frequency ◽

Shear Force ◽

Shaking Table Test ◽

Numerical Models ◽

Response Spectrum ◽

Shear Walls ◽

Shaking Table ◽

Seismic Force ◽

Code Provisions

A parametric study was performed to examine the seismic behaviour of moderately ductile (MD) reinforced concrete shear walls designed according to Canadian code provisions, including National Building Code of Canada (NBCC) 2010 and Canadian Standards Association (CSA) 23.3-04, when subjected to typical high-frequency eastern North America earthquakes. The numerical models were experimentally validated based on large specimens shaking table test results. The results obtained following the code response spectrum procedure were compared with the results from inelastic response history analyses to investigate the effect of higher modes on seismic force demands. The results indicate that current code provisions for MD shear walls need to be modified. A new base shear factor and shear force design envelop are proposed to evaluate the seismic shear force demand more realistically. This study also recommends that the current CSA 23.3-04 requirements for ductile shear walls for bending moments could be applied to constrain the location of inelastic flexural deformations at the base of MD shear walls.

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