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Ðàññìàòðèâàåòñÿ ìåòîäèêà ÷èñëåííîãî àíàëèçà âëèÿíèÿ óãëîâ àðìèðîâàíèÿ è ñõåìû ÷åðåäîâàíèÿ ñëîåâ íà ìàêñèìàëüíûå îêðóaeíûå äåôîðìàöèè ñëîèñòûõ êîìïîçèòíûõ öèëèíäðè÷åñêèõ îáîëî÷åê, íàãðóaeåííûõ îäíîêðàòíûì èìïóëüñîì âíóòðåííåãî äàâëåíèÿ.Êëþ÷åâûå ñëîâà: êîìïîçèòíûå ìàòåðèàëû, èìïóëüñíîå íàãðóaeåíèå, ÷èñëåííûå ìåòîäû. ÂâåäåíèåÊîìïîçèòíûå ìàòåðèàëû íà îñíîâå âûñîêîìîäóëüíûõ âîëîêîí íàõîäÿò øèðîêîå ïðèìåíåíèå ïðè ñîçäàíèè çàùèòíûõ ñèëîâûõ êîíñòðóêöèé, îáåñïå÷èâàþùèõ ëîêàëèçàöèþ ïðîäóêòîâ âçðûâà [1]. Èñïîëüçîâàíèå êîìïîçèòíûõ ìàòåðèàëîâ ïîçâîëÿåò ñîçäàâàòü êîíñòðóêöèè, îáëàäàþùèå ðÿäîì ïðåèìóùåñòâ (ìåíüøåé ìàññîé, ïîâûøåííîé òðåùèíîñòîéêîñòüþ, íåêàòàñòðîôè÷åñêèì õàðàêòåðîì ðàçðóøåíèÿ, îòñóòñòâèåì ñèëüíûõ ìàñøòàáíûõ ýôôåêòîâ) ïî ñðàâíåíèþ ñ àíàëîãàìè, âûïîëíåííûìè èç òðàäèöèîííûõ ãîìîãåííûõ ìàòåðèàëîâ. Ýêñïåðèìåíòàëüíî óñòàíîâëåíà [2] ñóùåñòâåííàÿ çàâèñèìîñòü ëîêàëüíûõ íàïðÿaeåíèé è äåôîðìàöèé â ñëîÿõ îò ðàçëè÷íîé îðèåíòàöèè ñèëîâûõ âîëîêîí íà óðîâíå ñëîÿ â ñëîaeíîì ñëîèñòîì ïàêåòå. Ïðè ýòîì âîçíèêàåò çàäà÷à ïîèñêà òàêîé ñòðóêòóðû ñëîèñòîãî ïàêåòà (óãëîâ àðìèðîâàíèÿ è ñõåìû ÷åðåäîâàíèÿ), êîòîðàÿ ïîçâîëèëà áû íàèáîëåå ïîëíî èñïîëüçîâàòü âûñîêèå aeåñòêîñòíûå è ïðî÷íîñòíûå õàðàêòåðèñòèêè êîìïîçèòíûõ ìàòåðèàëîâ ïðè ðàñòÿaeåíèè âäîëü ñèëîâûõ âîëîêîí.Öåëü äàííîé ðàáîòû -÷èñëåííûé àíàëèç âëèÿíèÿ óãëîâ àðìèðîâàíèÿ è ñõåìû ÷åðåäîâàíèÿ ñëîåâ íà ìàêñèìàëüíûå îêðóaeíûå äåôîðìàöèè ñëîèñòûõ ñòåêëîïëàñòèêîâûõ öèëèíäðè÷åñêèõ îáîëî÷åê ñî ñâîáîäíûìè òîðöàìè, íàãðóaeåííûõ îäíîêðàòíûì èìïóëüñîì âíóòðåííåãî äàâëåíèÿ îò âçðûâà â öåíòðå îáîëî÷êè ñôåðè÷åñêîãî çàðÿäà âçðûâ÷àòîãî âåùåñòâà (ÂÂ). *) Ðàáîòà âûïîëíåíà ïðè ÷àñòè÷íîì ôèíàíñèðîâàíèè Ïðîãðàììîé ãîñóäàðñòâåííîé ïîääåðaeêè âåäóùèõ íàó÷íûõ øêîë ÐÔ (ãðàíò ÍØ-2843.2012.8).ÏÐÎÁËÅÌÛ ÏÐÎ×ÍÎÑÒÈ È ÏËÀÑÒÈ×ÍÎÑÒÈ, âûï. 74, 2012 ã.

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Nonlinear three-dimensional problems of dynamic" deformation, buckling, and postcritical behavior of composite shell structures under pulsed loads are anal.~ed. The structure is assumed to be made of rigidlyjoined plates and shells of revolution along the lines cohwiding with the coordinate directions oJ'the joined elements. Individual structural elements can be made of both composite and conventional isotropic materials. The kinematic model of dc:]brmation of the structural elements is based on Timoshenko-.type hypotheses. This approach is oriented to the calculation of nonstationary deJormation processes in composite structures under small deformations but large displacements and rotation angles, and is implemented in the context of a simpl(]ied version of the geometrically nonlinear theory of shells. The physical relations in the composite structural elements are based on the theory of effi, ctive moduli for individual layers or for the package as a whole, whereas in the metallic" elements this is done in the framework of the theory of plastic flow. The equations of motion of a composite shell structure are derived based on the principle of virtual displacements with some additional conditions allowing for the joint operation of structural elements. To solve the initial boundary-value problem formulated, an efficient numerical method is developed based on the finite-d(lference discretization of variational equations of motion in space variables and an explicit second-order time-integration scheme. The permissible time-integration step is determined using Neummm's spectral criterion. The above method is especially efficient in calculating thin-walled shells, as well as in the case of local loads acting on the structural element, when the discreti:ation grid has to be condensed in the zones of rapidly changing solutions in space variables. The results of anal~ing the nonstationary deformation processes and critical loads are presented for composite and isotropic cylindrical shells reinforced with a set of discrete ribs in the case of pulsed axial compression and ~vternal pressure.An analysis of the studies dedicated to nonlinear nonstationary deformation and buckling of shell structures shows that the overwhelming majority of investigations deals with axisymmetric problems for smooth structural elements such as cylindrical, conic, and spherical shells, as a rule, made of traditional materials [1][2][3][4][5]. Only an insignificant number of nonlinear problems of dynamics and stability for composite shells of revolution under nonaxisymmetric pulsed loading has been solved [6-10].The number o fstudies dedicated to solution of the problems of nonstationary dynamics of shell structures is much smaller. Predominantly, the problems of dynamic deformation and stability of stiffened cylindrical shells have been investigated. In [ ! 1, 12], solution of the linear problems of dynamic deformation and strength of orthotropic cylindrical shells stiffened with longitudinal or annular rigid fibs under axial compressive forces...

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