Investigation of Methods of Preparing Horizontal Construction Joints in Concrete: Tests of Joints in Large Blocks

摘要

Three concrete blocks, 10 by 20 by 5 ft high, were cast in two 30-in.-high lifts. The 10- by 20-ft joint plane of each block was divided into four equal areas for testing different types of joint preparation. A series of strength tests (shear, tensile, and flexural) were made of cores drilled from several areas of each block to evaluate the various methods of preparing the horizontal construction joints. An analysis of the results indicated that there are no significant differences in effectiveness among the various joint treatments investigated in this program; therefore, it appears reasonable to select among the several treatments on the basis of cost. (Author)