## 1 Introduction
The sensitivity of the models to the assumed parameters for mass distribution and the connections between them means that dynamic models have not found widespread use in the assessment of the forces acting on steelwork. An attempt to use a numerical model based on the finite element method in the calculation of guiding forces was presented by [PERSON] and [PERSON] [24]. A shell-beam 3D model of the skip was loaded with displacements due to the misalignment of the guide rail. The results of the numerical analysis were compared with those of in situ tests conducted in the skip, resulting in agreement on force estimates and significant differences in displacements and stresses. However, the model did not take into account steelwork, which significantly affects the stiffness of the system. [PERSON] and [PERSON] [25] developed a model of steelwork and determined and calculated the dynamic coefficient for it; they showed that it depends on the characteristic of the force pulse and the point of force application. However, they did not model the entire conveyance in their study. Currently, the values of guiding forces are most often calculated based on those included in standards [26; 27; 28] and empirical formulas resulting from research conducted in the 1970s in South Africa [29]. In Poland, for the purposes of steelwork diagnostics, force measurements are made under operating conditions [30] using several approved methods. Empirical formulas contain generalizations and coefficients that are often adopted arbitrarily due to a lack of data, which significantly affects the results obtained. Field force measurements provide the best information on guiding forces, but they are costly and disrupt mine plants' operation. In addition, all the methods commonly used in Poland rely on the measurement of forces under roller guidance conditions. In the case of the failure of roller guides, there is contact with the steelwork of the sliding plates, which generates higher forces. Guiding force assessment methods based on discrete dynamic models have not been practically implemented in shaft operation and maintenance. The difficulty in their application is the need for a very precise description of misalignments that directly and strongly affect the equations of motion [31; 32]. The empirical methods implemented in standards [26; 27; 28] require the adoption of many problematic assumptions, such as the shape of the guide rail deformation [14; 15; 16; 17; 18]. The high safety requirements of the structure, which is subject to continuous deterioration due to corrosion and mechanical damage, require a method that allows for a frequent and accurate assessment of the guiding forces, preferably in real time. The presented, novel approach uses accelerometric measurements to assess and monitor guiding forces. On the basis of technical documentation and on-site inspection, a finite element model was developed, and numerical simulations of the impact of the skip on the steelwork were carried out. The results were compared with empirical formulas. The simulations allow for the assessment of the force of the sliding plate's action in the conditions of the failure of the roller shoe and, thus, reduce the uncertainty of force estimation, which has a positive impact on the reliability of the structure and the safety of its operation. This study was based on the actual shaft, on on-site inspections, and on measurements. The design solutions of the hoisting and guiding system are, however, typical for many shafts.