Water tower materials experimental investigations and technical condition assessment after 55 years of exploitation

摘要

The purpose of this work was to define the technical condition of the water tower building and an indication of the ways of repairing and strengthening the structure. The function of the building is to provide water under high pressure to water supply installation for a water railway distribution station. The structure was built in 1959. The building consists of four floors above the ground and the basement. The main masonry structure is made of brick casted on lime and cement mortar. Each story is separated by reinforced concrete ceilings constructed as two-way slabs supported by beams. A circumferential reinforced concrete water tank is situated on the top floor. The tank consists of two chambers with the total volume of 250 m3. Reinforced concrete stairs are located around the circumferential wall of the building and provide service and technological communication in the building. The roof is constructed with reinforced concrete panels. The scope of the study includes a technical condition assessment of masonry walls, reinforced concrete floors (slabs and beams), stairs, the tank and the dome. For this reason, experimental researches on structural elements were performed. Researches of structural concrete include destructive tests made on drilling trial elements and non-destructive tests, to qualify mechanical properties of the material. Supplementary tests concern the humidity measurements and concrete alkalinity examination. For detection of rebar in structural elements, scanning of the specimen surface was performed and the concrete cover was removed in several places. For brick walls the main attention was focused on moisture content measurements. Experimental investigations and on-site inspections made it possible to assess the level of consumption of individual elements and durability of the structure. On this basis, main guidelines for necessary repairs and strengthening of structural elements which endanger the safety of exploitation were proposed.