Manhole covers must provide adequate strength and durability over their intended lifespan. In addition to operating loads, the lifespan of cast-iron road covers is also strongly influenced by the conditions of installation and cover placement after opening or closing. Vertical displacement from the plane of the carriageway may occur during installation, the cover may eventually settle due to the material properties of the terrain on which it is placed, and the terrain around the cover may also settle. After opening and closing the lid, it often happens that the lid only partially touches the support surface due to stones or other impurities caught on the surface or cover. These events can significantly affect the lifespan of the cover.
As part of the master's thesis, we chose the type of cast-iron cover and then analysed it from the operational strength point of view. We first analysed its geometry and looked for potential critical points from a design point of view, we also determined the typical loads on the cover. We then set up a model that can simulate typical loads on a selected cast iron cover. In the simulations, we mainly analysed the impact of critical scenarios by dividing the impact parameters into individual levels. We evaluated the obtained results and proposed the improvement of the product or the necessary measures to achieve the intended operational strength.
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