Malakhov V. Strength and deformability of precast and cast-in-situ joints under static and dynamic loads

The object of research - loop joint of reinforced concrete bent elements disposed in the pure bending; goal - research work of loop joint used in bent elements arranged in the area of pure bending in different variants of its performance under dynamic loads; methods - Determination of the bearing capacity of the bent elements by mechanical loading; deformation measurement by elektrotenzometrick method and by mechanical devices; determination of the dynamic characteristics by the method of the instant removal of the load; determination of vibration characteristics of beams with various modifications of loop joints by method designs test in the mode of forced vibrations method; results - experimental results of the effect of transverse reinforcement area at the location of a loop joint with loop over the entire height of the cross section for strength and deformability of beams with loop joints; experimental results on the effect of the elements of forms faces for strength and deformability of beams with loop joints; new experimental data of the change of dynamic characteristics (natural frequency and logarithmic decrement of oscillations) in the formation of cracks in the loop joints area; new experimental data of changes in vibration characteristics (vibratory displacement, velocity and acceleration) due to cracking in the loop joints area; results of numerical studies of reinforced concrete beams with loop joints taking into account the non-linearity;the development and assembly of vibrator with directional exposure; vibrodiagnostics elements with loop joints introduced - during the design and construction of a sixteen-resort and recreation complex (Odessa) and residential building with underground parking (Kiev) in the development of state regulatory document DBN V.1.1-12-2014 "Construction in seismic regions of Ukraine" (Annex D). Namely, data of the results of experimental and theoretical studies of dynamic characteristics (frequency and decrement) studied beams with loop joints.