engleski

The Effect of the Bedding Length of Lintel in Masonry Walls on their Load Bearing Capacity

Lintels, i.e. reinforced concrete beams are used to bridge openings in masonry walls. In practice, bottom tensile reinforcement of the lintel is designed according to the ultimate bearing capacity under vertical load. In such cases, reinforcement is usually anchored very shortly above the opening. Under horizontal load, additional stresses may occur in the lintel. Under the great horizontal load, and especially under stronger earthquakes, significant cracks may occur in the lintel and its surrounding area. Damages in the lintel‘s area, among other, depend on the bedding length of the bottom reinforcement on wall supports and height of the lintel. With the greater height of a part of a wall above the opening, the contribution of the load bearing capacity of the lintel to the total bearing capacity of the wall becomes also greater. By using the previously developed numerical model for both static and dynamic analysis of concrete and masonry structures [1, 2], which can simulate their main nonlinear effects, the influence of the bedding length of bottom reinforcement on supports on the ultimate bearing capacity of some masonry walls with openings has been investigated. Three-storey masonry walls with door openings were analyzed. Unreinforced and confined masonry walls were considered. There were separately analyzed cases of masonry walls under horizontal static forces at the floor levels and cases of masonry walls under earthquake. The bedding length of the bottom reinforcement in the lintel and quality of the masonry were varied. Characteristic displacements of the walls and crack states in the lintel‘s area are shown. Finally, main conclusions and recommendations for practical application are given.

Masonry wall; opening; bedding length of lintel; numerical analysis

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