Structural integrity of brick-veneer buildings
Pace, Carl E.; Campbell, Roy L.
Technical reportAbstract: Floodproofing individual homes is an important aspect of the total solution of flood damage reduction. This report gives insight into the structural resistance of brick-veneer walls subjected to hydrostatic water loading. There are many variables affecting the response of a brick-veneer wall; therefore, the approach of this study was to obtain limited experimental data by testing three walls, analyze these data, and compare them to analytical solutions. Wall 1 was typical of the end wall of a house (no roof rafter or ceiling joist restraints). After about 2 ft of water, the wall deflections (order of magnitude of 10-3 in.) increased drastically for small increases in water depth and failed at about 2.4 ft of water. The analytical results for Wall 1 compare favorably with the experimental results. Wall 2 was constructed just as Wall 1 except it had a 3-ft x 6-ft 8-in.door in its center. The significant factors as indicated by the experimental results of Wall 2 are: a. In general, the wall deflected forward toward the water loading for low water loads; then, backward as the water depth became greater than 0.8 to 1.6 ft. b. The wall deflections were very small (10-3 in.) until 2 to 2.4 ft of water at which time the wall began to deflect drastically backward for small increases in water depth. c. Wall 2 (with door opening) deflected more forward but about the same backward as Wall 1. Wall 3 was constructed just as Wall 1 except it included roof rafter and ceiling joist restraints. The significant findings from the experimental results of Wall 3 are: a. In general, the roof rafter and ceiling joist restraints decrease the movement of the wall toward the water loading. b. The roof rafter and ceiling joist restraints are sufficient to cause a change in the failure mechanism from that which was experienced in Walls 1 and 2. The failure mechanism for Walls 1 and 2 was deflection and failure of the brick wall. The failure mechanism for Wall 3 was beam failure of the studs and a resulting collapse of the brick wall. c. The deflection of the brick wall begins to increase rapidly with water depth after about 1-1/2 ft but the increase is not as great as was experienced by Walls 1 and 2. This is indicated by the fact that the wall did not collapse until about 57 in. of water loading. d. Even though the wall can withstand greater water depths, it fails suddenly and totally when the stud wall fails. Based on the test results the upper bound for the failure of Walls 1, 2, and 3 was arbitrarily established at approximately 2 ft of water depth or at a deflection of 0.01 in. The structural integrity of brick- veneer Walls 1 and 2 was completely lost at about 2.4 ft of water loading. The type restraint did cause a change in the total capacity of the wall to resist hydrostatic loading because Wall 3 did not collapse until 57 in. of water loading had been attained. It is true that the finishing material on the inside of the studs will help strengthen the walls but this advantage is offset somewhat because no wave or debris loading was imposed on the walls in these tests. It is felt that without modifications a brick-veneer wall cannot be expected to withstand more than about 2 ft of hydrostatic pressure and if some safety factor is desired a limitation of 1- 1/2- ft of water should be imposed.
Concrete Laboratory (U.S.)Engineer Research and Development Center (U.S.)
Brick veneer; Buildings; Finite element method; Flood damage; Floodproofing; Hydrostatic pressure; Restraints; Structural stability; Walls
Technical report (U.S. Army Engineer Waterways Experiment Station) ; C-78-3.
Approved for public release; distribution is unlimited.