Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
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Engineering Characteristics of CLSM Using Bottom Ash and Eco-friendly Soil Binder

친환경 고결제와 저회를 활용한 유동성 복토재의 공학적특성

  • Park, Giho (Department of Civil Engineering, Korea National University of Transportation) ;
  • Kim, Taeyeon (Department of Civil Engineering, Korea National University of Transportation) ;
  • Lee, Yongsoo (Department of Civil Engineering, Korea National University of Transportation) ;
  • Lee, Bongjik (Department of Civil Engineering, Korea National University of Transportation)
  • Received : 2019.02.25
  • Accepted : 2019.04.08
  • Published : 2019.05.01
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Abstract

In general, pipe laying works are performed by constructing underground facilities such as pipes and then refilling the rest of the area with sand or soil. However, there are many problems in the compaction process such as difficulties in tampering around the underground facility and low compaction efficiency. Such problems cause deformation and damage to the underground pipes during refilling work and ultimately cause road sinks. Construction methods using CLSM are one of the typical methods to solve these issues, and recently, studies on CLSM using coal ash, which has similar engineering properties as sand, have been actively performed to protect environment and recycle resources. While many studies have been conducted to recycle fly ash in many ways, the demand for recycling bottom ash is increasing as most of the bottom ash is not recycled and reclaimed at ash disposal sites. Therefore, in order to find bottom ash applications using eco-friendly soil binders that are environmentally beneficial and conform with CLSM standards, this study investigated flow characteristics and strength change characteristics of eco-friendly soil binders, weathered granite soil, a typical site-generated soil, bottom ash, and fly ash mixed soil and evaluated the soil pollution to present CLSM application methods using bottom ash.

일반적으로 관매설공사는 관 등의 매설물을 시공하고 나머지 부분을 모래나 토사를 이용하여 되메우는 방식으로 진행된다. 그러나 매설물 주변의 다짐이 어렵거나 다짐효율이 떨어지는 등 다짐 시 많은 문제가 발생하고 있으며, 되메우기 공사 시 매설관의 변형과 파손을 유발하여 궁극적으로 도로함몰의 원인으로 발전하게 된다. 이러한 문제점을 해결하기 위한 방안 중 대표적으로 유동화토를 활용한 공법이 있으며, 최근 환경보호와 자원 재활용의 차원에서 모래와 공학적 성질이 유사한 석탄회를 활용한 유동화토에 관한 연구가 활발히 진행되고 있다. 석탄회 중 비회는 많은 연구가 진행되어 여러 방면으로 재활용이 이루어지는 반면, 저회는 대부분 재활용되지 못하고 회처리장에 매립됨에 따라 저회에 대한 재활용 요구가 증가되고 있다. 이에 본 연구는 친환경 고결제를 활용하여 환경적으로 유리하며 유동화토 기준에도 적합한 저회의 활용방안을 모색하기 위하여 친환경 고결제와 대표적인 현장발생 토사인 화강풍화토 및 저회, 비회 혼합토를 대상으로 유동특성, 강도변화 특성 등을 구명하고, 토양오염도 평가를 수행하여 저회를 활용한 유동성 복토재의 활용방안을 제시하였다.

Keywords

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Fig. 1. Flow test results according to the bottom ash mixing ratio

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Fig. 2. Flow test results according to the fly ash replacement ratio

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Fig. 3. CLSM unit weight according to the mixing ratio

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Fig. 4. Uniaxial compression strength according to the bottom ash mixing ratio

HJHGC7_2019_v20n5_23_f0005.png 이미지

Fig. 5. Uniaxial compression strength according to the fly ash replacement ratio

Table 1. CLSM design criteria

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Table 2. Characteristics of weathered granite soil

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Table 3. Chemical characteristics of bottom ash and fly ash

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Table 4. Physical characteristics of bottom ash and fly ash

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Table 5. Physical and chemical characteristics of eco-friendly soil binder

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Table 6. Summary of CLSM mixing design

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Table 7. Result of Heavy metals leaching test

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References

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