Lintels

This pre-cast lintel, shown in brown, is a structural support member used to distribute load coming from above. In this case, a stained glass window will be put above the lintel in the half-round area. Lintels distribute the load from above around the opening.

Because we are dealing with CMU, arching action is one property that can be found within these units. I would assume there is a purpose of the half round above the window in dealing with the load above. If you roughly draw a line from each end of the lintel, to the top of the half-round window, it roughly makes a 45 degree angle. The half-round would act as the 45 degrees necessary to spread the load out over the lintel. Arching action allows walls to carry and deflect more load than if AA didn't take place. Below is a digram to help further illustrate the role of arching action. The slides are taken from class lectures.

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