Mažų gelžbetoninių tiltų Kauno rajone būklės tyrimai

Abstract

The projected analysis of solutions on prefab reinforced concrete bridges built on the roads of local importance is presented in this paper. The earlier and at present adjusted requirements for concrete and reinforcement used for the construction of bridges are described in the paper as well.Possible and generally occurring defects on prefab reinforced concrete constructions during the construction and exploitation time have been analysed. The main reasons for their rise have been named. The condition of 36 bridges situated in Kaunas district has been researched according to the made methodical. During the research of crannies in the reinforced concrete constructions, it has been decided that 10% of bridge span panels and beams have crannies because of loads and 75% - because of reinforcement corrosion. The length of crannied carpet is 3.2 m/panel, 1.2 m/beam. Even in 44 % of panels and beams there is reinforcement unprotected with concrete. Analogically could be evaluated and the following bridge members: poles, grillages, bed strengthening in the underbridge, bridge cover,bridge parapets. The researches of concrete strength in constructions by non-deteriorated method have been carried out too. The received results showed that compression strength of concrete for analogical bridge details is very different - variation coefficient meanings fluctuates from 22.7% to 38.2%.