Dynamic Strength Study of Small, Fixed-edge, Longitudinally Restrained Two-way Reinforced Concrete Slabs


Book Description

Increases in ultimate strengths of 23.7 (Series I) and 24.6 (Series II) percent under dynamic loading were obtained. Theoretical slab strengths were determined. Modification of the equations used allowed good predictions of tensile membrane resistance of the static slabs. The equations were used to predict peak pressures sustained by the dynamic slabs.




An Analysis of the Dynamic Strengths of Reinforced Concrete Slabs


Book Description

Ultimate strength equations are summarized for square, simply supported reinforced concrete slabs, and these equations are used to predict the dynamic ultimate and collapse strengths of three slabs. The predicted strengths are compared with experimental results from airblast load tests, and the extent of damage to the slabs is shown under over-pressures approximately equal to the predicted strengths.







Strength and Behavior of Reinforced Concrete Slab-column Connections Subjected to Static and Dynamic Loadings


Book Description

The objectives of this investigation were to study the strength and behavior of slowly (statically) loaded reinforced concrete slab-column connections and to determine the effect of rapid (dynamic) loading on the strength and behavior by comparison with the static test results. Nineteen full-scale models of a connection and adjoining slab area, consisting of a simply supported slab 84 or 94 inches square and 6-1/2 inches thick loaded concentrically on a 10- or 20-inch-square stub column at the center of the slab, were tested. The main variables were the amounts of reinforcement in the slab (p = 0.75 and 1.50 percent), the column size, and the loading speed. Eight specimens were loaded to failure statically, two were subjected to a very rapidly applied load of short duration, and nine were loaded to failure by a rapidly applied load with a rise time chosen to represent the conditions in a blast-loaded structure. The static test results are compared with 12 shear strength prediction methods. Differences between the mechanism of shear failure in slabs and beams are examined. (Author).




Expedient Upgrading of Existing Structures for Fallout Protection


Book Description

This study was conducted in support of the Defense Civil Preparedness Agency's (DCPA) Crisis Relocation Planning (CRP) program in which existing structures will be upgraded to provide fallout shelters for a relocated population. A demonstration test was conducted in which a residential dwelling was upgraded by placing soil against the walls and on the roof of the structure. The shelter was large enough to house 80 people. Upgrading was accomplished partially by hand labor and machinery. The test showed that a conventional structure could be upgraded and that the shelter occupants using tools and materials found in most homes could if necessary upgrade their shelter during the expected 2- or 3-day period of crisis relocation preceding a nuclear attack.