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<br />finite element method to model and analyze walls of buildings and to determine <br />safe water loads. Analytical studies can be performed more quickly and less <br />expensively than an experimental study, and factors such as building strength <br />or house modifications can be analyzed. <br />In the analytical study, the solutions for the deformations of the exper- <br />imental wall as tested can be obtained by the finite element method. The ma- <br />terial properties, geometry, boundary conditions, and loading had to be known <br />to model and get the solution for the brick walls. Plate elements can be used <br />to model the brick wall if the material properties (modulus of elasticity (El, <br />shear modulus (G), and Poisson's ratio (~)) are known. After the analytical <br />solution was obtained, the experimental results were used to compare and eval- <br />uate the analytical method. <br />In the determination of material properties, it was concluded that tests <br />on brick or mortar individually would not give the needed properties because <br />the wall was made of a composite of the two materials. Tests on sections of <br />brick and mortar laid as in the walls were conducted to determine the compos- <br />ite properties. The E values were calculated and averaged; the average <br />value obtained and used in the analytical computations was 5.7 x 106 psi. <br />Shear tests were performed to give some indication of the shearing strength of <br />the brick wall at the mortar joints. The shearing strength was approximately <br />10 psi. <br />From past experience, it was concluded that the finite element solution <br />for the brick wall would not be very sensitive to Poisson's ratio and shear <br />modulus; therefore, Poisson's ratio was estimated as 0.3 and G, then calcu- <br />lated from E and ~ by the equation G = E/[2(1 + ~)] G was calculated <br />to be 2.2 x 106 psi. <br />As the brick walls were constructed, samples of mortar were taken at the <br />one-third, one-half, and two-thirds positions of construction. Specimens <br />taken were eighteen 2-in. diam by 4-in. high and six 6-in. diam by 12-in. high <br />cylinders. The 6- by 12-in. specimens were tested at 28 days and the average <br />material properties for the mortar were as follows: <br /> <br /> fc = 1,100 psi <br /> Ev = 0.8 x 106 psi <br /> ~ = 0.11 <br />These values were obtained <br />in constructing the walls. <br /> <br />to document the characteristics of the mortar used <br /> <br />14 <br />