Static analysis of a stepped main shaft in a mine hoist by means of the modified 1D higher-order theory

Abstract

The analysis of a stepped main shaft by 1D refined beam theories in cylindrical coordinate system is presented. High-order displacement fields are achieved by employing the Carrera unified formulation (CUF), which takes direct implementation of any-order theory without the requirement of considering special formulations. The classical beam theories can be derived from the formulation as particular cases. The principle of minimum potential energy is used to obtain the governing differential equations and the related boundary conditions in a cylindrical coordinate system. These explicit terms of the stiffness matrices are exhibited and a global stiffness matrix is then obtained by matrix transformation. For the special working condition in a mining hoist and stepped shaft, the resulting global stiffness matrix and the loading vector are modified and applied with the boundary conditions in the static analysis of shaft parts. The accuracy of static analysis based on the refined beam theory is confirmed by comparing ANSYS solid theory and classical beam theories. An experiment for verifying the availability of the modified 1D refined beam model on the surface strain of segment 9 of the main shaft is conducted in a field experiment at Zhaojiazhai Coal Mine, China. Experimental results demonstrate the practicability of the present theory in predicting the strain field on the surface of the stepped main shaft of a mining hoist.

摘要

目 的

研究基于 Carrera 通用表达式的一维高阶理论, 将其应用于矿井提升机主轴的力学特性分析, 针对矿井提升的特殊工况对主轴模型进行改进, 并探究该改进模型在工况监测中的可用性。

创新点

基于 Carrera 一维高阶理论, 建立提升机主轴的一维高阶模型; 根据矿井提升的特殊工况对主轴模型进行改进, 得到改进的主轴一维高阶模型。

方 法

• 1. 引入基于 Carrera 通用表达式的一维高阶理论, 克服传统梁理论的局限性和三维有限元法计算经济性差等问题;

• 2. 通过理论计算、 软件仿真和现场试验(图14 和15), 验证改进的主轴一维高阶模型的有效性和可用性。

结 论

• 1. 基于 Carrera 通用表达式的一维高阶理论模型能够以较少的计算量得出与 ANSYS 三维实体模型相近的结果;

• 2. 改进的提升机主轴一维高阶模型能够准确地监测矿井提升系统的工况。