OPTIMIZING CONVENTIONAL DESIGN METHODS FOR REINFORCED CONCRETE RAFT FOUNDATIONS

Abstract

Without a proper design and construction of foundations, problems such as cracking, settlement of buildings may occur and even to the extent that a whole building may collapse within its design life. Therefore, a proper and adequate foundation system is required to maintain the safety of a building. This presentation is the modeling of the requirements of compression reinforcements in raft foundations. The model helps to confirm a valuable provision to supplement the conventional theoretical design. For validation, a reinforced concrete raft foundation is modeled which is designed according to the current European code. Results indicate that there is differential settlement within the raft foundation based on the settlement and stress patterns obtained from a coded finite element model. This is followed by the addition of compression reinforcement from 0.1% to 0.9% based on the cross sectional area of the raft slab until uniform settlement is obtained. The results obtained suggest that a suitable percentage of the concrete cross section area of raft slab foundations should be used as compression reinforcement in order to prevent differential settlements. The required nominal area of compression reinforcement is 0.9% of the cross section area of the concrete section.

http://dx.doi.org/10.4314/njt.v33i4.9