A concrete failure due to shortage in shear resistance is the most serious type of failure because shear failures are preceded by little, if any, deflections or cracking to give advance warning. Basically, the problem here is that engineers do not know whether- and to what extent- reinforcement acts together and simultaneously with the concrete in resisting shear. Neither do they know how the torsional stress induced by non-symmetrical loading influences the maximum shearing stress to be resisted. But this much we do know, that all shear failures result from: (1) a lack of knowledge of what requires resistance; (2) not properly applying all available data to the problem; (3) not providing the correct concrete strength or dimension; (4) not providing the right amount of reinforcement or positioning it properly. A considerable test program was carried on at the laboratories of the Portland Cement Association. Here 13 one-third scale models of the second span in the typical Air Force design frame were tested to failure. The first seven beams were tested to failure under flexural loading only and the last six were subjected to a combined flexure and axial tension. Only the latter beams failed under flexural loadings in a manner similar to the actual frames. Based on these tests, four conclusions were reached. (1) Just as it takes time to make good bread, it takes time to make good concrete. (2) Expansion joints serve their purpose only when they operate and frozen joint details are worse than no joints. (3) In our present basic designs the lateral restraint of all members is taken for granted. But this restraint must definitely be provided especially at the compression faces of continuous structures. (4) If the torsional strain set up in the beam can absorb the normal expansion with less internal distress while also absorbing the stresses induced by the bending supporting columns, then the girders will defect laterally in a sine curve pattern and rotate the columns. If the girder is not braced or reinforced to compensate for this torsional strain, it will crack.