Sustainable Serviceability of Structural Concrete

Abstract

<p>Long-term deflection of concrete grids is predicted by iterative application of elastic analysis. The grid consists of short elements of prestressed concrete beams. The procedure applies to floors and bridge decks, including irregular solid slabs with beams or drop panels. The grid is assumed horizontal and is subjected to gravity loads and prestressing forces. The displacements are considered at five degrees-of- freedom: two translations and two rotations about horizontal cartesian axes and a downward deflection. The effects of cracking, creep and shrinkage of concrete and relaxation of prestressed reinforcement are analyzed by equilibrium and compatibility equations, avoiding the use of empirical multipliers. The analysis considers the effect on serviceability of cracking induced by construction loads at early age of concrete.</p>