Seismic assessment of out-of-plane loaded unreinforced masonry walls in multi-storey buildings

A procedure is proposed to evaluate the dynamic out-of-plane stability of cracked unreinforced masonry (URM) walls located in multi-storey URM buildings. The equations of dynamic motion are derived from first principles and representative single-degree-of-freedom (SDOF) models are proposed. The models have nonlinear stiffness properties that correspond to the restoring gravitational forces. A method is suggested to transform the nonlinear problem to a corresponding linear equivalent so that conventional spectral methods can be used to calculate wall response. The dynamic interaction between the URM building as the main structural system and the out-of-plane loaded walls as secondary elements is addressed by developing floor response spectra. Several buildings were assumed in a parametric study and subjected to code-compatible ground motion records. The absolute acceleration response at floor levels was calculated and the response spectra for that modified acceleration were subsequently obtained. The results from the study suggest that modifications should be made to the equations proposed for the Parts response spectra in the New Zealand seismic loading standard, NZS 1170.5:2004, in order to calculate the spectral response of out-of-plane loaded URM walls. Several worked examples are presented to demonstrate application of the procedure.

[1]  Arturo Tena-Colunga,et al.  Seismic Evaluation of Unreinforced Masonry Structures with Flexible Diaphragms , 1992 .

[2]  A. Page.  Finite Element Model for Masonry , 1978 .

[3]  K. Tan,et al.  Strengthening of Masonry Walls against Out-of-Plane Loads using Fiber-Reinforced Polymer Reinforcement , 2004 .

[4]  Cb Monk.  Transverse Strength of Masonry Walls , 1955 .

[5]  Donald W. White,et al.  Nonlinear analysis of a one-story low-rise masonry building with a flexible diaphragm subjected to seismic excitation , 2004 .

[6]  P. Benson Shing,et al.  Interface Model Applied to Fracture of Masonry Structures , 1994 .

[7]  G. Housner.  The behavior of inverted pendulum structures during earthquakes , 1963 .

[8]  Robert G. Drysdale,et al.  Rehabilitation of Masonry Walls using Unobtrusive FRP Techniques for Enhanced Out-of-Plane Seismic Resistance , 2006 .

[9]  Michael C. Griffith,et al.  Out-of-Plane Behavior of One-Way Spanning Unreinforced Masonry Walls , 2013 .

[10]  Jason Ingham.  The influence of earthquakes on New Zealand masonry construction practice , 2008 .

[11]  Paulo B. Lourenço,et al.  A micro-mechanical model for the homogenisation of masonry , 2002 .

[12]  Adrian Page,et al.  Finite Element Model for Masonry Subjected to Concentrated Loads , 1988 .

[13]  J. Ingham,et al.  Seismic Zonation and Default Suite of Ground-Motion Records for Time-History Analysis in the North Island of New Zealand , 2012 .

[14]  David J. Goodman,et al.  Personal Communications , 1994, Mobile Communications.

[15]  Kenneth J. Elwood,et al.  Assessment of ASCE 41 Height-to-Thickness Ratio Limits for URM Walls , 2007 .

[16]  J Wilson,et al.  AS 1170.4-2007 commentary: structural design actions, part 4: earthquake actions in Australia , 2007 .

[17]  Nicos Makris,et al.  The rocking spectrum and the limitations of practical design methodologies , 2003 .

[18]  Y. Belmouden,et al.  An equivalent frame model for seismic analysis of masonry and reinforced concrete buildings , 2009 .

[19]  Felix Y Yokel,et al.  Strength of Load Bearing Masonry Walls , 1971 .

[20]  P. Lourenço,et al.  A micro-mechanical homogenisation model for masonry: Application to shear walls , 2009 .

[21]  A. C. Costley,et al.  Dynamic response of URM buildings with flexible diaphragms , 1995 .

[22]  Nelson Lam,et al.  Time–history analysis of URM walls in out-of-plane flexure , 2003 .

[23]  G. Magenes,et al.  EVALUATION OF OUT-OF-PLANE STABILITY OF UNREINFORCED MASONRY WALLS SUBJECTED TO SEISMIC EXCITATION , 2003 .

[24]  A. Mosallam.  Out-of-plane flexural behavior of unreinforced red brick walls strengthened with FRP composites , 2007 .

[25]  Can Celalettin Simsir,et al.  Influence of Diaphragm Flexibility on the Out -of -Plane Dynamic Response of Unreinforced Masonry Walls , 2004 .

[26]  M. J. N. Priestley,et al.  Seismic behaviour of unreinforced masonry walls , 1986 .

[27]  K. Zeuli,et al.  in the US , 2004 .

[28]  Jason Ingham,et al.  Out-of-Plane testing of an unreinforced masonry wall subjected to one-way bending , 2008 .

[29]  Jaroslav Vaculik.  Unreinforced masonry walls subjected to out-of-plane seismic actions. , 2012 .

[30]  Michael C. Griffith,et al.  Airbag testing of multi-leaf unreinforced masonry walls subjected to one-way bending , 2013 .

[31]  David J. Dowrick.  Damage and intensities in the magnitude 7.8 1929 Murchison, New Zealand, earthquake , 1994 .

[32]  S.-Y. Chen,et al.  A macroelement for the nonlinear analysis of in-plane unreinforced masonry piers , 2008 .

[33]  Michel Bruneau.  State-of-the-art report on seismic performance of unreinforced masonry buildings , 1994 .

[34]  Michael C. Griffith,et al.  Out-of-plane assessment of an unreinforced masonry wall: Comparision with NZSEE recommendations , 2009 .

[35]  Oded Rabinovitch,et al.  Nonlinear Dynamic Behavior of Unreinforced Masonry Walls Subjected to Out-of-Plane Loads , 2008 .

[36]  Lindita Kellezi.  Dynamic Soil-Structure-Interaction , 1998 .

[37]  Sergio Lagomarsino,et al.  The Assessment of Damage Limitation State in the Seismic Analysis of Monumental Buildings , 2009 .