Effect of Friedel's salt on strength enhancement of stabilized chloride saline soil

作     者：CHENG Yin LI Zhan-guo HUANG Xin BAI Xiao-hong 程寅;李战国;黄新;白晓红

作者机构：School of Transportation Science and Engineering Beihang University College of Architecture and Civil Engineering Taiyuan University of Technology 

出 版 物：《Journal of Central South University》 (中南大学学报（英文版）)

年 卷 期：2017年第24卷第4期

页      面：937-946页

核心收录：

学科分类：0810[工学-信息与通信工程] 0806[工学-冶金工程] 081401[工学-岩土工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0814[工学-土木工程] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：Project(51008007)supported by the National Natural Science Foundation of China Project(2013318J01100)supported by the Science and Technology Project of Ministry of Communications,China 

主　　题：chloride saline soil stabilized soil Friedel’s salt strength enhancement effect 

摘      要：In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fill, an artificial chloride saline soil, and a non-saline soil were stabilized by Portland cement(PC) and PC with Ca(OH)_2(CH) with different contents. A series of unconfined compressive strength(UCS) tests of stabilized soil specimen after curing for 7 d and 28 d were carried out, and the hydration products and microstructure of the specimens were observed by X-ray diffractometry(XRD), scanning electronic microscopy(SEM), and energy-dispersive X-ray analysis(EDXA). The results showed that the strengths of PC+CH-stabilized chloride saline soils were much higher than those of PC-stabilized soils. A new hydration product of calcium aluminate chloride hydrate, also known as Friedel s salt, appeared in the PC+CH-stabilized chloride saline soils. The solid-phase volume of Friedel s salt expanded during the formation of the hydrate; this volume filled the pores in the stabilized soil. This pore-filling effect was the most important contribution to the significantly enhanced strength of the PC+CH-stabilized chloride saline soils. On the basis of this understanding, a new optimized stabilizer was designed according to the concept that the chloride in saline soil could be utilized as a component of the stabilizer. The strength of the chloride saline soils stabilized by the optimized stabilizer was even further increased compared with that of the PC+CH-stabilized soils.