The goal of our research is to develop an optimal model of asphalt concrete pavements of bridges under thermal stress. The development of the model was stimulated by the demand to assess the effect of temperature stresses on the destruction of asphalt concrete pavement of bridges while keeping spending to the minimum, which led to the need to choose, if possible, the simplest model. The search was carried out according to the criterion of compliance with the results of numerical modeling in an elastic setting. As a result of the study, we have made the following conclusions: -maximum tensile stresses occur in the upper layers of asphalt concrete; -the increase in stresses caused by the uneven distribution of temperature over the thickness of asphalt concrete does not exceed 7 % in the elastic setting, and taking into account stress relaxation this can be ignored; -an increase in the rigidity of the base under the asphalt concrete layer by a factor of 1000 leads to an increase in stresses of not more than 10 % in the elastic setting, which gives reason to use the considered model for both metal and reinforced concrete bridges.

The paper discusses the results of research in forming fast erecting pneumatic framework structures with the use of pneumatic rings and spirals. We investigate the description of structures, methods of erecting and dismantling, working features and applying such pneumatic structures as covering with opening ends, wavy vault with transformable semiarches, elastic volume supported by pneumatic pillars, flexible sheathing with pneumatic supporting frame for vault coverings, sheathing for column concreting, elastic funnelled volume, device for assembling rigid building structures. Description of pneumatic structures is illustrated by explanatory schemes and figures.

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This article presents the major results obtained during the research of the effect of temperature factors on the formation of cracks in asphalt concrete pavements of bridges. The main problem was divided into a number of parts: determination of temperature field in pavement; creation of an engineering design model for determining the stress-strain state caused by temperature deformation; determination of asphaltic concrete rheological characteristics; introduction of criteria for assessing the durability of asphaltic concrete pavement.

Interesting results obtained while forming structures with the use of single-petalous hyperbolic paraboloids are presented in this paper. Two main methods of forming compound shells are discussed. Formation possibilities are illustrated by examples, such as box beams and columns with walls made of hypars, bunkers and vertical silos, support elements in foundation that work under vertical load with large eccentricity, folded structures, vaulted and domed radial shells that have various plan views. The structures, mentioned above, are made of hypars with straight edges.