Дослідження напружено-деформованого стану триплексів при експлуатації в умовах знижених температур

Abstract

Досліджено напружено-деформований стан (НДС), який виникає в тришарових клеєних скляних конструкціях – гомогенних та гетерогенних триплексах з обрамленням та без нього, в результаті температурних впливів на конструкцію.

Triplex glass is widely used for glassing vehicles (automobiles, railway vehicles, aircrafts and ships), windows and facades of buildings. Such constructions often work under sudden drops in temperature [extreme temperatures]. Therefore, the research of the stressed-strained state of triplexes in exploitation at low temperatures is of a great topicality The aim of the work is to research the stressed-strained state (SSS) appearing in the three-layered glued glass constructions: homogeneous and non-homogeneous triplexes with and without framing line, as a result of temperature influences. The problem has been solved with the polarized-optical method (POMM) – method of photoelastisity. The idea of modeling had been considered and implemented before analyzing SSS in full scale samples, in order to create and practice the methods of temperature load and research, as well as destruction of samples. Herewith, the same materials were chosen for triplexes models and full scale samples. Experimental conditions lied in determining the stressed-strained state (SSS) in the explored triplexes during the decrease of temperature from room T=293K to the fixed values of T = 273, 253, 233, 213 K and identifying the moment of their destruction. The method of integrating differential equations of equilibrium in finite differences has been used for the stress separation. According to the research objectives the maximum tangential (critical) stresses τmax and normal stresses σх and σу formed in the zones of glued surfaces contact have been defined. The distribution of normal stresses σх directed at each point along the gluing in triplexes, stress σу directed perpendicular to the gluing layer and tangential stresses τmax are presented graphically. The analysis of the received results has been conducted. The testing data indicates that the fracture of heterogeneous triplexes without framing line occurs at temperatures ~ 268 K, and with the frame line - at temperatures ~ 245 K. Moreover, the process of destruction takes place in the layer of silica glass in parallel with the gluing. In other samples the destruction in the researched range of temperatures was not observed. The reason for the destruction of heterogeneous structures is, evidently, the character of SSS, changing from compressive stresses at the edges of samples to stretching stresses in the middle of the sample. This situation leads to the detachment of silica glass and its destruction. The testing data can be used in glassing vehicles (automobiles, railway vehicles, aircrafts and ships), windows and facades of buildings.