Brick Particulate Additives for Concrete

The spacing of brick particulates (distance between particle surfaces) is linearly related to the particle diameter for a given volume concentration. Freezing-thawing cycles expressed as the number of cycles required to produce 0.2% residual expansion is plotted versus spacing in Fig. 29 for cement paste, w/c = 0.50 and wet cured for 28 days. There is a dramatic increase in the number of cycles when the spacing is reduced below 0.8 mm. 

Residual length changes of concrete specimens subjected to freezing-thawing cycles and containing brick particles (total porosity, 16%) are recorded in Table 1. The basic concrete mix had a cement aggregate sand ratio 1 2.75 2.25 and a water cement ratio of 0.58. The spacing factors for the concretes listed in Table 1 were 0.046, 0.013,0.033, 0.029, and 0.033 respectively. 

therefore, apparent that incorporation of suitable porous brick particles in the plastic mix increases the freezing-thawing resistance of hardened concrete without the serious shortcomings of the conventional air-entrainment method, i.e., instability of bubbles and strength reduction. 

Applied Clay Mineralogy, p. 422, McGraw-Hill, New York (1962) 

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