Publication details
Abstracts and keywords
The work presents an analysis of the wind impact on a building-scaffolding system. The analysed issue concerned wind load of façade scaffoldings without protective cladding, mounted at buildings with no openings. The work begins with the classification of the most common scaffoldings on the market and the description of the standard recommendations regarding the impact of wind. The main focus was on the wind load procedure, specifying the method of determining individual parameters defining the load. A comprehensive literature review concerning the impact of wind on scaffoldings was carried out, divided into model and in-situ tests, as well as numerical simulations. The Computational Fluid Dynamics – CFD was selected as the basic research tool. The simulation results were validated using in-situ measurements. Therefore, it was necessary to describe the basics of CFD, paying special attention to the used models. The most important part of the research concerned in-situ studies and CFD simulations. Full-scale tests were carried out on dozens of facade scaffoldings erected in various regions of Poland. Based on the measurements of wind speed and wind direction, the analysis of time and spatial distribution of wind speed was presented. The measured 10-minute values were compared with those determined according to the standard approach. Other analyses were performed using CFD. A validation procedure was carried out to select the appropriate turbulence model based on the calculation of the 2D flow of one, two and ten scaffolding stands sections. The results were compared with the data available in the literature. The selected turbulence model was then used to simulate the flow around the building with scaffolding. A series of parametric analyses were carried out, including changes in the wind attack angle, level of building façade details, various spacing between the scaffolding and the building. Based on the conducted in-situ tests and CFD simulations, main conclusions were formulated. First of all, it was found that simulations can be used to analyse flows around the building-scaffolding system. It was noticed that the scaffolding placed next to the building did not increase the effect of wind load on the façade of the building, and the flow pattern of the building resulting from its shape had a decisive influence on the wind load of the scaffolding. It is very important to state that for complex building shapes, the scaffolding wind load estimation can be based on CFD analysis of the flow around the building itself. In addition, the stands located in the first row next to the building were less loaded. Regardless of the angle of attack, the dominant wind load direction on the scaffolding stands is parallel to the façade. The largest values of velocity occurred near the stands located at the corners of the building. Stands located beyond the edge of the building are exposed to a much larger wind than others, even those at the corner. The shielding effect of scaffolding elements occurs only if the wind direction is parallel to the line of their setting, so it should not be included in the calculations, because in reality the wind direction is not constant.
