The Increment of Shear Strength and Compression Modulus during Soft Ground Improvement

Based on the ground improvement project of Jiangyin Rail Spur Line in Fuzhou City,the applicability of four ground improvement methods commonly used in practice( including heap preloading by plastic drainage pile and heap preloading by sand pile,vacuum combined heap preloading by plastic drainage pile,heap preloading by plastic drainage pile and cement-mixed pile) are studied. Based on the data from in-site tests,in-site monitoring and laboratory tests,introducing two new parameters into the standard formulas,two empirical formulas for the increase of shear strength and the increase of compression modulus are proposed. These two empirical formulas,which reflect the increasing of soft ground mechanical indexes with the preloading,can provide some reference for the similar project in the coast area of southeast China.