DETERMINATION OF THE DEFORMABILITY OF THE TERIVA PRECAST-MONOLITHIC OVERLAPPING STRUCTURAL SYSTEM USING HYDROSTATIC METHOD

The scientific work is devoted to a comprehensive study of a stress-strain state of energy-efficient precast-monolithic overlapping, which has been in the process of construction for some amount of time. A practical assessment of the physical and mechanical characteristics of the materials used in construction was carried out. Statistical verification of the obtained data was carried out using the author's methodology and in accordance with the requirements of Ukrainian and European building codes. The Teriva precast-monolithic overlapping is one of such solutions. The Teriva interfloor ceiling is a high-quality alternative to expensive monolithic and standard overlapping slabs. The technology combines reliability, manufacturability, ease and quick installation without a crane. Teriva is a precast-monolithic structure consisting of load-bearing beams and hollow blocks - fillers. The assembled structure is poured with a thin (3 cm) layer of concrete and forms a lightweight interfloor ceiling. The object of the study was a section of a precast-monolithic reinforced concrete overlapping measuring 1.0×6.0 m. The precast-monolithic overlapping was tested under the action of short-term and long-term evenly distributed loads and was carried out in accordance with the method of hydraulic testing of slabs and shells, taking into account the requirements of DSTU B V.2-6-7-95. According to the given experimental program, the loading mode is set: stepwise (when assessing deformability and bearing capacity in accordance with current standards), monotonically increasing or active with subsequent unloading. The load level determines the height of the water column in the tank. Based on this method, when studying the deformability and strength of the interfloor overlapping under consideration, a stepwise loading mode was selected with each step being held in time until the devices completely stop. The step size was set within 1-2 kN/m2. The maximum design load on the floor was 8 kN/m2. To determine the deflections of the loaded overlapping, mechanical deflection gauges 6 PAO and the SIIT-3 strain gauge system with DPI-100 sensors were used, installed under the floor of the 2nd floor on the floor of the 1st floor at the most characteristic points. The SIIT-3 system is designed to measure the output signals of strain gauges with the presentation of the results in digital form. The system performs sequential polling of a given number of measuring channels; preliminary analog processing (modulation, amplification and synchronous demodulation) of the measured signals and their conversion into digital form by the push-pull integration method with subsequent display of the measurement results and the numbers of the measuring channels on a digital display. According to the results of observations, the deformation did not exceed the permissible ones (the maximum permissible deflection is 20 mm, and the actual one is 0.22 mm). At the same time, the created load level exceeded the calculated one by almost 2 times. Moreover, deformations from long-term loads also exceeded the permissible ones and amounted to about 0.22 mm. Also, no signs of destruction were found. As a conclusion, it is accepted that the bearing capacity of the floor is sufficient to withstand the loads.