Physics, Astronomy & Geo Sciences

The Dangers of Brick in a Concrete Jungle: a comparative investigation into the into the role of foundation materials in earthquakes

The purpose was to compare the effects of lateral forces caused by seismic activity on concrete and masonry (brick) foundations. It was hypothesized that due to its higher comprehensive strength, ductility, and durability, a cast-in-place concrete foundation will withstand seismic forces better than a masonry (brick) foundation. To test this hypothesis, a simulation was used with a computer program. The procedure consisted of modeling both a typical lightly reinforced cast-in-place concrete foundation, and a lightly reinforced masonry (brick) foundation. An axial live load of 200 lbs and an axial dead load of 200 lbs was applied to both, to simulate actual conditions. A lateral load, to model what would be caused by a seismic event, was then applied to each foundation. The initial lateral load was 0.5 kips (500 lbs). The load was increased by 0.5 kip increments up to 3.0 kips. After each load was imposed, the Flexure Moment Demand and Moment Capacity were recorded for each foundation. The data showed that the ratio of Moment Capacity to Moment Demand, or the Safety Factor (F.S.), was significantly lower during the Masonry trials than the Concrete trials. This confirms the hypothesis made: under lateral seismic pressures, a concrete foundation will likely perform far better than a masonry foundation.