Krul Y. Composite superstructures of a new type.

The thesis is devoted to development and research of design of the steel-reinforced concrete structure of auto-road bridge of new type and also to methods of rationalization and management of its characteristics. Rationalization criterias are justified and internal and external control parameters are identified for the proposed systems. Based on the obtained theoretical data a new constructive solution of span structure is formed, in which the compressed part is presented in the form of lightweight concrete slab, the stretched one is presented as the space-metal part, which consists of perforated plates. A new approach to determine the characteristics of hardness of steel-reinforced concrete block of box intersection at pure torsion is proposed. The problem of dynamic stability is solved, based on the definition of the critical static and dynamic load and also critical wind speed. Experimental research of model of steel-reinforced concrete structure is conducted. The experiment confirmed the fact of the robust collaboration of concrete slab with the metal portion of the model. Analysis of the results gives the indication of the high rigidity of the system and shows the elastic work of materials. It should be noted that the nature of the deformation system confirms the correctness of compiled theoretical models and experimental data coincide with theoretical ones with the divergence, which does not exceed 15%.