An overview of possible test parameters is provided in Table 4. Not all parameters given in Table 4 were tested in this study; as an initial test series reported in this paper, rates of water leakage across a deficient joint were evaluated in relation to simulated wind-driven rain loads (i. e., water deposition rate and pressure differential). The degree of deficiency of the joint was dependent on the degree of joint displacement (i. e., movement in extension) and specific “crack characteristics," such as crack location (adhesion) and crack length. Essentially, and as will be discussed in a subsequent section, the size of the crack opening in the deficient joint and through which water might penetrate, is a function of the degree of joint extension and crack length.
However, the notional list of possible test parameters permits considering those results that might be obtained from, for example, testing joints: of different width and depth (or varying W/D ratios); with backer rods of varying size or type; in compression as opposed to expansion; having different types of cracks
FIG. 8—Front elevation of test specimen showing horizontal joint, location of crack in joint.
TABLE 4—Experimental parameters.
Building (fagade) condition
TABLE 5—Rainfall area. a
aWidth 0.1 m, height 0.55 m
(i. e., adhesive at the interface of the sealant and substrate as compared to a crack along center of joint); and cracks of increased size as compared to that evaluated in this study.
The different water deposition rates to which the specimens were subjected are provided in Table 4 and the corresponding rates of water flow necessary to produce these rates are given in Table 5. On the vertical joint, the “rainfall area,” was the area over which water was deposited to ensure a uniform rate over the crack (i. e., 0.1 m wide by 0.55 m high).