ISSN: 1546-962X
CODEN: JAIOAD
Page Count: 10

Deflection Criteria for Masonry Beams

Bennett, RM
Professor, The University of Tennessee, Knoxville, TN

McGinley, WM
Professor, North Carolina A & T State University, Greensboro, NC

Bryja, J
Manager Technical Services, General Shale Products Corporation, Johnson City, TN

(Received 31 October 2005; accepted 20 November 2006)

Abstract

This paper examines issues related to deflection criteria for masonry beams. Masonry walls supported by beams and lintels act compositely with the beam. As the height of the masonry wall increases, the behavior becomes more like that of a tied arch, with the masonry in compression and the beam acting as the tension tie. Deflection limits are only needed so that sufficient stiffness is provided during construction to prevent serviceability problems, with the suggested limit being I/600. Several methods for determining the deflection of reinforced masonry beams are examined, and a method for the effective moment of inertia of cracked reinforced sections is recommended. Beams and lintels that exceed this deflection do not necessarily have to be increased in size, but rather shores could be used during construction. Masonry beams and lintels with I/d≤8 should not be controlled by deflections. Therefore, it is recommended that the code not require these members to be checked for deflections.

Keywords:
masonry, beam, lintel, deflection, stiffness, limits

Paper ID: JAI100442
DOI: 10.1520/JAI100442
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