Economic Technical Feasibility of Modified Geopier RAP

Tales Moreira de Oliveira, Jordan Lopes Albino, Leandro Neves Duarte, Tulio Pena da Silvaand Erivelto Luís de

Souza

Federal University of São João del Rei, Ouro Branco, Brazil

Abstract: Rammed Aggregate Piers (RAP) by Geopier consists in a technique of soil improvement used for both granular and cohesive soils. This technique has some goals, such as: the increase of bearing capacity, the general improvement of stability of structures related to soil-structure interaction, and the reduction and acceleration of the displacements coming from consolidation. Its application, when used simultaneously with shallow foundations, can increase the bearing capacity and reduce the primary settlement, if it is compared to the same situation and soil without the use of this technique. The proposed modified RAP piles constitutes a simplified construction of the RAP pile that has been altered to be constructed with smaller diameters, about 15 cm, using steel slag as a granular material, and is performed using the SPT hammer as a compaction element. Its main objective is the application in foundations of buildings of medium to small size. This report the feasibility of the Modified RAP piles, through the design of different models of foundations normally applied in Brazil in a hypothetical geotechnical situation. The modified RAP piles for small diameters obtained a low cost, and it showed up to be viable and advantageous application.

Key words: economic viability, granular piers, soil improvement