Kovalchuk V. Determination of thermal stresses and deformations in bridge structures

The dissertation is devoted to the solution of actual scientific and practical problem of determining the thermal stresses and deformations of concrete, metal and composite spans of railway and road bridges that are sustained to the action of variable temperature extremes of the environment. The results of experimental measurements of temperature distribution on the surface of reinforced concrete beams of railway bridge and road overpass, composite and metal beams and railway bridges.The models for engineering evaluation of thermal stresses and strain beam bridge structures that occur at variable temperature changes of the environment are offered. Here are the results of numerical calculations of thermal stresses and deformations by finite element method and by using thermo elasticity theory.The methodological support is described and the device for measurement of the temperature stresses and deformations of beams spans of bridges is developed. Also the method for determining thermal stresses in variable ambient temperatures is proposed.The scientific and practical recommendations for determining thermal stresses and strains in span beams of bridges are developed, temperature gradients in the vertical direction and the horizontal cross-section of span beams of bridges are proposed.Тhe estimation of economic efficiency and the payback period for a new device for determining thermal stresses and deformations of span beam structures of bridges is conducted.