Melnik A. Torque rigidity and strength of reinforced concrete box-section elements of the normal fissures

Object of research - reinforced concrete box section elements with normal cracks; goal - development of methodology for determining the torsional stiffness of reinforced concrete elements with cracks normal to the box-section elements, the development of engineering methods of calculation of stiffness and strength; methods - method of computer modeling of structures with the use of software systems that implement the finite element method (at the time of many studies), the numerical-analytical method using differential equations and methods of differential and integral calculation (is the development of numerical and analytical methods for determining the torsional rigidity of reinforced concrete elements with normal cracks), experimental studies on physical samples, the use of program complex "Mathcad" (in the computer program of determining the parameters of stiffness and torsional strength of reinforced concrete elements under study); results - solved the problem of determining the stiffness and the torsional strength of reinforced concrete box section with normal cracks, developed numerical - analytical method for determining the torsional rigidity of reinforced concrete box section with normal cracks, developed a numerical method for determination of VAT reinforced concrete box section with normal cracks, taking into account the nonlinear properties of concrete , developed by an engineering method of determining the internal forces in elements of box-section, in which torque is applied to the top shelf, developed and proposed engineering method for calculating the strength of box-like elements with normal cracks, which allows calculation of reinforced concrete elements of this section without the use of software systems; novelty - first experimentally obtained dependence of the "torque-twist" for the elements box section with normal cracked reinforced with longitudinal reinforcement; first obtained experimental dependence of the torque to the destructive elements of box-section with normal cracks, the first time developed a numerical method for determining the torsional rigidity of reinforced concrete box section with normal cracks, taking into account the nonlinear properties of concrete and the use of the finite element method, first developed engineering methods for determining the stiffness and the torsional strength of reinforced concrete box section with normal cracks, has been further developed numerical-analytical method for determining the torsional stiffness of the elements of normal cracks, which developed the elements of box-section; implemented - in development of regulatory documents for the design and the learning process.