Code 729 the First Iranian Guideline for Strength-based Design of Non-Structural Masonry Walls: A Verification Report

Document Type : Original Article

Author

Ph.D., Behsazan Larzeh Davam Co., The Science and Technology Park of University of Tehran, Tehran, Iran

Abstract

In 2017, the first Iranian guideline for strength-based seismic design of non-structural masonry walls, Code 729, published by The Plan and Budget Organization of Iran. Code 729 uses strength-based procedure and the yield-line theory to design unreinforced and reinforced non-structural masonry walls with or without openings. In this paper, first a brief overview of Code 729 is presented and then using a comprehensive experimental database of 72 full-scale masonry walls, accuracy of the code is demonstrated. It is seen that Code 729 can estimate out-of-plane capacity of different masonry walls with good accuracy. According to the results, average, median, and median plus one standard deviation of errors of the Code 729 in estimating out-of-plane capacity of masonry walls, respectively, are 20%, 18%, and 33.2% and with a probability of 85% the error would be less than 34%. Considering the complicated two-way orthotropic behaviour of non-structural masonry walls and their highly uncertain properties, such level of error is deemed to be acceptable for practical applications. In addition to experimental results, Finite Element simulations are also carried out in this study to shed more light on out-of-plane behaviour of walls with different opening details.

Keywords


[1]-Ryder, J. F., 1963, The use of small brickwork panels for testing mortars, Transactions of the British Ceramic Society, pp.62.
[2]-Willis, C. R., 2004, Design of unreinforced masonry walls for out-of-plane loading, PhD Thesis, School of Civil and Environmental Engineering, The University of Adelaide, Adelaide, Australia.
[3]- West, H. W. H., Hodgkinson, H. R, and Haseltine, B. A., 1977, The resistance of brickwork to lateral loading-Part 1: Experimental methods and results of tests on small specimens and full sized walls, The Structural Engineer, The Journal of the Institute of Structural Engineers, 55, 10, 411-421.
[4]- Lawrence, S. J., 1983, Behavior of brick masonry walls under lateral loading, PhD Thesis, The University of New South Wales.
[5]-Drysdale, R. G. and Essawy, A. S., 1988, Out-of-plane bending of concrete block walls, Journal of Structural Engineering, ASCE, 114, 1, 121-133.
[6]- Chong, V. L., 1993, The behavior of laterally loaded masonry panels with openings, PhD Thesis, School of Civil and Structural Engineering, University of Plymouth, Plymouth, UK.
[7]- Griffith, M. C., Vaculik, J., Lam, N. T. K., Wilson, J. and Lumantarna, E., 2007, Cyclic testing of unreinforced masonry walls in two-way bending, Earthquake Engineering and Structural Dynamics, 36, 6, 801-821.
[8]-ACI 530-13, 2013, Building code requirements and specification for masonry structures, American Concrete Institute, Farmington Hills, Michigan.
[9]- Eurocode 6, 2005,Design of masonry structures- Part 1-1: general rules for reinforced and unreinforced masonry structures, CEN –European Committee for Standardization, Brussels.
[10]-AS 3700, 2001, Masonry structures, Standards Australia, Sydney.
[11]-Code 729, 2017, Guideline for seismic design of non-structural masonry walls reinforced with bed joint reinforcement, No. 729, Deputy of Technical and Infrastructure Development Affairs, Plan and Budget Organization, Tehran, Iran.