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Lab 1- Construction of Masonry Wall and PrismsLabMasonry Wall Initial Rate of Absorption Mixing Mortar Mortar Workability Mortar Air Content Prism Construction ExtrasLab Handout Sample Lab Report PhotosLab Equipment and MaterialsExtra ResourcesLab WorksheetPrinter Friendly Version |
General description: Initial rate of absorption or IRA is defined as the number of grams of water absorbed in one minute over 30 square inches of brick bed area (ASTM C67). Acceptable values range from 10 to 30 grams. Dry brick, with an IRA above 30, should be wetted before laying. A simplified test for measuring IRA (the one used in this lab) is to place 20 drops of water in a quarter sized area on a brick and time its absorption. If the water is absorbed in under one and a half minutes the brick should be wetted prior to laying. If a brick is too dry, it will absorb too much water out of the applied mortar, weakening the bond. |