Title:
Large-Deflection Response of Fully Grouted Reinforced Masonry Walls to Static and Dynamic Out-of-Plane Pressure
Author(s):
Robert S. Browning, John M. Hoemann, and James S. Davidson
Publication:
Symposium Paper
Volume:
281
Issue:
Appears on pages(s):
1-20
Keywords:
blast load; full-scale testing; large deflection; load-deflection response; moment-area method; reinforced masonry; resistance function; single-degree-of-freedom (SDOF) modeling
DOI:
10.14359/51683619
Date:
12/27/2011
Abstract:
This paper presents improved methods for calculating the ultimate strength and ultimate deflection of fully grouted reinforced concrete masonry walls. The behavior considered was out-of-plane flexure caused by both static and dynamic loads. The objective was to provide an improved methodology for the design of blast-resistant reinforced masonry walls. Static tests were performed on two single-wythe walls and one cavity wall using a vacuum chamber. The resulting load-deflection responses were compared to an analytical resistance function. The resistance function was then used in a single-degree-of-freedom model to predict the dynamic response to explosive loading. These predictions were compared with results from full-scale explosive testing. The resistance function developed here explicitly defines the deflections at which cracking and yielding occur. It also provides a direct method for calculating the allowable deflection, rather than relying on tabulated rotation limits. Furthermore, through static and dynamic experiments, it was found that the addition of a non-structural brick veneer to a structural wythe can significantly increase the ultimate deflection by overcoming P-delta stability effects, but that it has little effect on the overall strength. The methodology developed here has been successfully implemented and provides a more robust definition of strength and ductility while still maintaining efficiency and practicality.