SIMULATION OF THE STRESS-STRAIN STATE OF THIN-WALLED POLYCARBONATE DOMES FOR RATIONAL DESIGN

The paper contains the further developed of method for calculating thin-walled dome systems without a stationary foundation. Have been carried out the detailed analysis of the fundamental design solutions for frameless collapsible spherical polycarbonate domes, which are used by modern world manufacturers of these structures. Have been done a brief description of the momentless theory of the operation of spherical shells, which is adapted for polycarbonate domes. Have been considered a simplified analytical model of the stress-strain state of a spherical shell with an equatorial diameter of up to 5 m under the influence of climatic influences for the subsequent verification of detailed models. Have been developed highly detailed finite element models of domes of different sizes, taking into account technological openings and structural stiffeners (support ring and door frame) under the wind, snow, ice loads and under other climatic influences. Have been identified the fragments with the highest stresses from various loads and forms of the deformation of the structure. Have been considered separately the issues related to the loss of shape stability, position and balance of a thin-walled spherical shell, as a light temporary structure. Have been proven that the worst influence on the dome structures is the wind influence, based on the stability criterion. Have been determined the estimated value of the aerodynamic lifting force from wind effects on the dome. Have been proven that the lifting force far exceeds the stabilizing force of the weight of a thin-walled dome. Have been revealed with the help of the performed calculations, it was that a frameless spherical polycarbonate dome inevitably loses its balance stability due to the action of wind loads and requires unfastening with anchors. Have been proposed a rational method for anchoring dome structures at temporary earthen construction sites using geo-screws or metal screw piles. Have been revealed the addiction between the radius of curvature of a spherical dome and the rational thickness of polycarbonate based on the criteria of stiffness and strength. Have been formulated the constructive recommendations regarding the rational design of polycarbonate dome systems. Have been developed the technological regulations for the further safe operation of domes, and have been outlined the directions for further scientific research on this topic.