Experimental study on properties and environmental impacts of steel slagcement stabilized aggregates(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2021年5期
- Page:
- 43-53
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Experimental study on properties and environmental impacts of steel slagcement stabilized aggregates
- Author(s):
- HUANG You1; LIU Zhaohui1; LIU Li1; LAN Tianzhu2; FU Yeyang1
- (1. School of Traffic and Transportation Engineering, Changsha University of Science and Technology,Changsha 400114, Hunan, China; 2. Guangxi Transportation Science and Technology Group Co.,Ltd., Nanning 530007, Guangxi, China)
- Keywords:
- road engineering; steel slag; cement stabilized aggregate; base course; mechanical property; volumetric stability; environmental impact
- PACS:
- -
- DOI:
- -
- Abstract:
- The feasibility of utilizing steel slag in road base was investigated and optimum steel slag content was determined, mechanical properties, volumetric stability as well as environmental influences were evaluated. Microstructure of surface was examined by the scanning electron microscope (SEM), element distribution was characterized by the Xray fluorescence test and metal constitute was determined by flame atomic absorption spectrophotometer (FAAS). Four levels of steel slag contents (0%, 30%, 50%, 75%, volume fraction, the same as below) were blended into mixtures with different cement contents (3%, 4%, 5%, 6%, mass fraction, the same as blew). Tests of unconfined compressive strength, unconfined compressive modulus, bending strength and volume stability were conducted. Heavy metal precipitation of different cement contents, particle sizes and salinities were also checked. The results show that steel slag has good engineering mechanical properties, and is beneficial for strength, stiffness and dry shrinkage of cement treated aggregates. Overall best performance is obtained at 50% replacement of steel slag. Volume expansion of steel slag can be effectively prevented by means of CH3COOH or silica fume, but the addition of silica fume should be controlled below 4.5%. There is higher risk of heavy metal precipitation when cement content is low, steel slag is small or salinity level is high. Large size steel slag (particle size is greater than 4.75 mm) and higher cement content is recommended to ease environmental burden based on heavy metal precipitation analysis. More concerns should be raised in coastal areas where steel slag may be exposed to salty water surroundings. With proper control in the process of production and application, steel slag is a very promising alternative material to be utilized in cement stabilized base course in road engineering. 7 tabs, 12 figs, 30 refs.
Last Update: 2021-09-30