{"title":"ON THE ASYMPTOTIC SOLUTION OF THE AXISYMMETRIC PROBLEM OF FUNCTIONALLY GRADED HOLLOW SPHERE IN RADIALLY DIRECTION","authors":"N.K. Akhmedov , A.H. Sofiyev","doi":"10.1016/j.tws.2025.113352","DOIUrl":null,"url":null,"abstract":"<div><div>In this study, the axisymmetric problem of functionally graded (FG) transversely isotropic spheres in the radial direction, which do not contain 0 and Pi poles, is investigated within the framework of 3D-elasticity theory. In this study, firstly, the elasticity theory of spheres made of homogeneous materials extended to the elasticity theory of functionally graded transversely isotropic (FGTI) spheres. Arbitrary stresses are applied to the slots that keep the hollow sphere, whose lateral surface is assumed to be fixed, in balance. Asymptotic formulas are obtained to calculate the displacements and stresses of FGTI hollow spheres for the first time. The solution of the problem consists of solutions belonging to the nature of the boundary layer localized in the slots (conical sections) inside the sphere, which is equivalent to the Saint-Venant boundary effect for FG plates. Unlike the FG isotropic sphere, weak transitional boundary layer solutions that spread far from the conical sections for FGTI spheres emerge. In addition, an asymptotic solution to the torsion problem for thin FGTI spheres is presented for the first time. The realized asymptotic solutions can be a criterion for determining the fields of application of the existing applied theories of FGTI spheres. Based on the proposed solutions, more accurate new applied theories for heterogeneous transversely isotropic spherical shells can be constructed. Finally, the changes in displacements and stresses compared to the homogeneous case are analyzed in detail when the modulus of elasticity changes linearly and inversely proportional to the radius.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"214 ","pages":"Article 113352"},"PeriodicalIF":5.7000,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Thin-Walled Structures","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0263823125004458","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CIVIL","Score":null,"Total":0}
引用次数: 0
Abstract
In this study, the axisymmetric problem of functionally graded (FG) transversely isotropic spheres in the radial direction, which do not contain 0 and Pi poles, is investigated within the framework of 3D-elasticity theory. In this study, firstly, the elasticity theory of spheres made of homogeneous materials extended to the elasticity theory of functionally graded transversely isotropic (FGTI) spheres. Arbitrary stresses are applied to the slots that keep the hollow sphere, whose lateral surface is assumed to be fixed, in balance. Asymptotic formulas are obtained to calculate the displacements and stresses of FGTI hollow spheres for the first time. The solution of the problem consists of solutions belonging to the nature of the boundary layer localized in the slots (conical sections) inside the sphere, which is equivalent to the Saint-Venant boundary effect for FG plates. Unlike the FG isotropic sphere, weak transitional boundary layer solutions that spread far from the conical sections for FGTI spheres emerge. In addition, an asymptotic solution to the torsion problem for thin FGTI spheres is presented for the first time. The realized asymptotic solutions can be a criterion for determining the fields of application of the existing applied theories of FGTI spheres. Based on the proposed solutions, more accurate new applied theories for heterogeneous transversely isotropic spherical shells can be constructed. Finally, the changes in displacements and stresses compared to the homogeneous case are analyzed in detail when the modulus of elasticity changes linearly and inversely proportional to the radius.
期刊介绍:
Thin-walled structures comprises an important and growing proportion of engineering construction with areas of application becoming increasingly diverse, ranging from aircraft, bridges, ships and oil rigs to storage vessels, industrial buildings and warehouses.
Many factors, including cost and weight economy, new materials and processes and the growth of powerful methods of analysis have contributed to this growth, and led to the need for a journal which concentrates specifically on structures in which problems arise due to the thinness of the walls. This field includes cold– formed sections, plate and shell structures, reinforced plastics structures and aluminium structures, and is of importance in many branches of engineering.
The primary criterion for consideration of papers in Thin–Walled Structures is that they must be concerned with thin–walled structures or the basic problems inherent in thin–walled structures. Provided this criterion is satisfied no restriction is placed on the type of construction, material or field of application. Papers on theory, experiment, design, etc., are published and it is expected that many papers will contain aspects of all three.