Bearing Walls with Core(s)
A core is little more that two, three or four bearing walls placed perpendicular to each other in order to create a "closed" geometry. Tubes, round or square, can resist torsional loading and are very stiff. A core can be added to the typically parallel alignment of the bearing walls in order to create a lateral load resistance in a direction perpendicular to the bearing walls. Otherwise, the parallel walls can collapse like dominoes.
The core is often placed in a central location. This is due to the convenience for the distribution of building services AND for an increased structural integrity. Off-center placement of a core can create torsional rotational loadings that might require additinoal resistance mechanisms. Bearind walls with core(s) allow for a greater free floor area and is thus more popular for office buildings than the parallel Bearing Wall systems. This is a common system for reinforced concrete structures of moderate height.
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© 1996 Chris H. Luebkeman