Evaluation of Rocking and Toe Crushing Failure of Unreinforced Masonry Walls

Abstract

The objectives of this study are to evaluate the variables that affect the shear behavior of unreinforced masonry (URM) walls and to propose the equation of the rocking and toe crushing strength of URM walls by regression analysis using the test data including the previous research. The main variables are the axial stress, the aspect ratio and the thickness of URM walls. The test results show that the specimens are governed by rocking and toe crushing failure modes. The relationship of the shear strength is proportionate to the square root of the vertical axial stress, and the relationship of the shear stress and aspect ratio is linearly proportional. Shear strength and cross sectional area are not proportional. For the URM walls tested, the proposed rocking and toe crushing strength/actual strength ratio of 0.95, and coefficient of correlation R of 0.9889 are more appropriate than the FEMA 306 rocking and toe crushing strength formulas.

Keywords

unreinforced masonry wall (URM wall)shear behavior shear strength rocking failure toe crushing failure axial stress aspect ratio regression analysis

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References

Abrams

D.P.

(1992). “Strength and behavior of unreinforced masonry elements”, Proceedings of the 10th World Conference on Earthquake Engineering (WCEE), Madrid, pp. 3475–3480.

Antonine

Magonette

and Magenes

(1994). “Shearcompression testing and analysis of brick masonry walls”, Proceedings of the 10th European Conference on Earthquake Engineering, Vienna, pp. 1657–1662.

Benedetti

and Casella

M.L.

(1980). “Shear strength of masonry piers”, Proceedings of the 7th World Conference on Earthquake Engineering (WCEE), Istanbul, pp. 167–174.

FEMA 306. (1999). Evaluation of Earthquake Damaged Concrete and Masonry Wall Buildings, ATC-43 Project for The Partnership for Response and Recovery, Washington, D.C., pp. 249.

Konig

Mann

and Otes

(1988). “Experimental investigation on the behavior of URM walls under seismically induced loads and lessons derived”, Proceedings of the 9th World Conference on Earthquake Engineering (WCEE), Tokyo-Kyoto, pp. 1117–1122.

Magenes

and Calvi

G.M.

(1992). “Cyclic behavior of brick masonry wall”, Proceedings of the 10^th World Conference on Earthquake Engineering (WCEE), Madrid, pp. 3517–3522.

Kwon

K.H.

(2001). “Development of Retrofitting Method of Unreinforced Masonry Structures”, PhD Thesis, University of Seoul, pp. 263.

Manzouri

Schuller

M.P.

Shing

P.B.

and Amadei

(1996). “Repair and retrofit of unreinforced masonry structures”, Earthquake Spectra, Vol. 12, No. 4, pp. 903–922.