DETERMINATION OF BENDING OF A BEAM FROM A NONLINEAR DEFORMABLE MATERIAL BY RITZ-TIMOSHENKO METHODS AND FINITE DIFFERENCES TAKING INTO ACCOUNT DEGRADATION FUNCTIONS OF CROSS SECTION RIGIDITY

The article solves the problem of determining the deflections of a beam made of a nonlinearly deformable material - a polyester composite held in water using the numerical methods of Ritz-Timoshenko and finite differences. The influence of the aggressive environment on the material of the structure was taken into account by introducing the degradation function of the stiffness of the element cross-sections into the calculation algorithms of the above methods. The problem of determining the time and conditions for the onset of the limiting state of the structure in the second group in accordance with the current norms and rules has been solved.