关海土木论坛_高速路.pdf

Available online at (2008) 192–198 /locate/enggeoEngineering Geology 97Utilization of a new soil stabilizer for silt subgrade Zhi-Duo Zhu ?, Song-Yu Liu Communication College, Southeast University, Nanjing, China Received 30 June 2007; received in revised form 31 December 2007; accepted 20 January 2008 Available online 5 February 2008Abstract Silt cannot satisfy the requirements of highway construction because of its low strength. A new stabilizing agent (SEU-2) was developed to improve the mechanical performance and applicability of silt in road. Laboratory tests, including unconfined compression and shrinkage tests, were performed. Test results show that the new stabilizing agent can significantly increase the strength and the water stability, and decrease the shrinkage strain of silt. Field tests were also carried out and the results indicated that the new stabilizing agent could effectively improve the entire stiffness of subgrade. From the point of view in mechanics and applicability in road, adding 4% new stabilizing agent is an economic and reasonable method to stabilize the silt. The stabilized silt has high early strength, small shrinkage deformation, and high entire stiffness. It can satisfy the requirements of highway subgrades. ? 2008 Elsevier B.V. All rights reserved.Keywords: Highway; Stabilization; SEU-2 stabilizing agent; Subgrade; Silt1. Introduction Silt is a kind of sedimentary geomaterial consisting primarily of very fine particles, including fine sand particles, silt particles, and some clay particles which are often less than 10% by weight. Silt is a type of transitional soil between sand and clay. A soil is defined as silt if its plasticity index is no greater than 10 and the amount of particles greater than 0.075 mm is no greater than 50% of the total (MCPRC and GAQSIQPRC, 2002). The minerals in silt are predominantly quartz, feldspar, and mica. Consequently, silt has weak linkage among grains and low activity, which usually does not satisfy