Probability analysis of loss of preload for elastic-plastic threaded structure with stochastic parameters under random excitation

• Published in: Structures (Oxford) Vol. 76; p. 108982
• Main Authors: Yu, Kuahai, Jia, Yuanqing, Sheng, Xiangqian, Niu, Lanjie, Xiao, Jing, Li, Jie
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2025
• Subjects: Finite element analysis; Loss of preload; Moment method; Stochastic analysis; Threaded structure; Threaded structure; Stochastic analysis; Finite element analysis; Loss of preload; Moment method
• ISSN: 2352-0124; 2352-0124
• DOI: 10.1016/j.istruc.2025.108982

Threaded structure with stochastic parameters, as the most important components of engineering structures, are usually subject to the random excitations in their service environment. The probability analysis of loss of preload for threaded structure is an important indicator for assessing the failure of threaded structure. Therefore, this paper investigates the loss of preload for threaded structure under dynamic excitation using a proposed stochastic analysis method. A refined model of the elastic-plastic threaded structure under axial alternating excitations is developed and validated through comparison with experimental data and theoretical formulations. To facilitate stochastic analysis of the elastic-plastic thread structure, an accurate and efficient point estimation method is introduced through the polynomial dimension convergence criterion, and the probability density function and cumulative distribution function of the stochastic response are approximated using the shifted generalized lognormal distribution. According to the proposed method, the loss of preload for threaded structure with stochastic parameters under random excitation is investigated, in which the structural parameters, Young’s Modulus of threaded structure, and the amplitude of excitation are treated as random variables. The effects of number of cycles of excitations and the distribution of random variables on preload loss are systematically explored. These results demonstrate that the probability distribution of preload loss stabilizes as the number of cycles increases, and different distribution types have a remarkable effect on the probability distribution of loss of preload, in which a total of 667 finite element analyses were carried out for the proposed method. Overall, this paper provides a methodology to assess the probability of loss of preload for elastic-plastic threaded structure with stochastic parameters under random excitation, which can enhance the suitability for threaded structure.