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The interpretation of some building codes regarding the spacing of lateral supports or the limiting of the stresses in masonry walls for stability against wind pressures seem to vary among engineers. To emphasize the need for a clarification of the codes in this matter, the results of an analytical study of hollow block masonry walls is presented. From this study graphs have been prepared for ease of evaluating the stability of a masonry wall based on its combined strength in the vertical and horizontal directions. [ABSTRACT FROM AUTHOR]

Development of criteria for the prediction of thermal stresses in concrete dam construction block during cooling operations prior to grouting is outlined. A new concept is presented concerning the tensile stress within a block which inc I udes the ratio of the height of the temperature transition zone to the base length of the block being cooled. It is shown that high temperature gradients in a concrete block will lead to excessive tensile stresses resulting in cracking of the block. Control of the maximum stress may be achieved through cooling operations leading to acceptable temperature gradients. Several curves are given for prediction of maximum tensile stress as a function of base length, height of temperature transition zone, temperature change, and properties of the concrete. [ABSTRACT FROM AUTHOR]

Reports the effects of various factors on tensile and shear bond of masonry mortars with a view to establishing a basis for recommendations for obtaining strong joints. Tests were conducted to determine the effect of mortar materials, specimen storage, mortar mixes, variations in block composition, differences in block curing, and type of masonry assemblage. Also in one test series the tensile bond of epoxy adhesives used in place of mortar was investigated. [ABSTRACT FROM AUTHOR]

Presents the results of carbonation and shrinkage studies of nonplastic, expanded slag concrete made with and without fly ash. Test specimens were subjected to moist, low pressure steam and high pressure steam curing conditions. Five different storage conditions including normal air drying, oven drying, and carbonation treatments at various ages and concentrations were used. All specimens were subjected to a final carbonation and two wet-dry cycles at the end of the storage period. Test results show that some carbonation treatments are effective in reducing later shrinkage. [ABSTRACT FROM AUTHOR]

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