Efficiency of Improvement Techniques for Moderate Thickness Weak Soil Layers in Port Said

Abstract

Engineers may replace weak soil that extends to a relatively large thickness or use a deep foundations solution. These solutions may be expensive and sometimes have difficulties in implementation on-site. The other alternative solution is to improve the soil properties. In this paper, several methods for soil improvement were experimentally studied. Partial soil replacement of weak soil by replacing 10% to 30% of its thickness, dynamic compaction using different impact energies, and dynamic replacement with different dynamic replacement depths were studied. Comprehensive laboratory tests were performed on a soil profile model constructed in a square wooden box of 1.60 x 1.60 m and a depth of 1.20m. The tested soil profile consisted of 60 cm sand and the top layer of 40 cm weak soil imported from a construction site in Port Said city. Kinetic compaction energy was calculated for both laboratory and in-situ conditions. The effectiveness of each improvement method was demonstrated and discussed. Finally, recommendations to guide geotechnical engineers in selecting a suitable method for improving such soil types were concluded.