UTILIZATION OF RECYCLED COAL MINING WASTE FOR ROAD FOUNDATION LAYERS IN VIETNAM

Authors

  • Tong Ton Kien Hanoi University of Civil Engineering
  • Pham Thi Vinh Lanh 2Construction faculty, College of Technical and Construction No1, Hanoi, Vietnam

Keywords:

Coal Mining Waste (CMW), California Bearing Ratio (CBR), Road Bases and Subbases Materials, Macadam Aggregates, Recycled Aggregates (RAs)

Abstract

Road foundation is commonly used crushed aggregates from natural stone or gravel, natural sand, or soil with natural gravel. However, nowadays the sources of natural materials have been increasingly exhausted. This promotes the search and utilization of other materials to replace these natural materials for road construction projects. Meanwhile, the total volume of coal mining waste (CMW) released from coal exploitation in Vietnam has reached 460 million m3/year. This waste is mainly the disposal of soil-rocky waste mountains at coal mining sites, which leads to waste natural resources and landfill areas. Therefore, this research focus on using CMW as recycled aggregates to replace natural aggregates. It is not only to minimize the consumption of natural resources and solve the shortage of raw materials for road construction but also to reduce the mammoth volume of CMW at coal mining fields. This paper focuses on compaction characteristics and California Bearing Ratio (CBR) of CMW recycled aggregates (RAs) for the subgrade and foundation layers application. The results show that the maximum dry density (MDD) of the recycled sand (Dmax=4.75mm) ranges from 1.695-1.912 g/cm3, the optimum moisture content (OMC) of 15.1-18.1%, and the CBR value reaches 33-44%. As for graded macadam (Dmax=25mm) has the MDD=2.091-2.307 g/cm3; OMC=5.1-6.7% and CBR= 89-123%. These results proved that it is possible to use CMW as recycled sand to replace natural sand and macadam aggregate type II Dmax=25mm as bases and subbases pavement for sub-surface foundation layers in Vietnam.

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Published

2021-11-30 — Updated on 2021-11-30

How to Cite

Kien, T. T. ., & Vinh Lanh, P. T. . (2021). UTILIZATION OF RECYCLED COAL MINING WASTE FOR ROAD FOUNDATION LAYERS IN VIETNAM. GEOMATE Journal, 21(87), 11–18. Retrieved from https://geomatejournal.com/geomate/article/view/1342