• Computers and Concrete
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• v.5 no.5
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• pp.491-501
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• 2008

The present study verifies compressive strength, ultrasonic pulse velocity, electrical resistance,permeable ratio, and shrinkage from waste glass controlled low strength materials (WGCLSM) and early-high-strength WGCSLM specimens, by replacing the sand with waste glass percentages of 0%, 10%,20%, and 30%. This study reveals that increasing amounts of waste LCD glass incorporated into concrete increases WGCLSM fluidity and reduces the setting time, resulting in good working properties. By increasing the glass to sand replacement ratio, the compressive strength decreases to achieve low-strength effects. Furthermore, the electrical resistance also rises as a result of increasing the glass to sand replacement ratio. Early-high-strength WGCSLM aged 28 days has twice the electrical resistance compared to general WGCSLM. Early-high-strength WGCSLM aged 7 days has a higher ultrasonic pulse velocity similar to WGCSLM aged 28 days. The variation of length with age of different compositions is all within the tolerance range of 0.025%. This study demonstrates that the proper composition ratio of waste LCD glass to sand in early-high-strength WGCSLM can be determined by using different amounts of glass-sand. A mechanism for LCD optical waste glass usage can be established to achieve industrial waste minimization, resource recycling, and economic security.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1203-1206
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• 2001

The main intent of this research is to determine the feasibility of utilizing bottom ash as CLSM(Controlled Low-strength Materials). The durability tests including permeability, repeated wetting and drying, freezing and thawing for bottom ash CLSM were conducted. Laboratory test results indicated that CLSM using bottom ash has acceptable durability performance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.53-54
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• 2015

As the result of uniaxial compression strength test on the CLMS mixing BFS and SS with BFS 4000, it required to determine the desired strength through increasing unit quantity of cement in mixing process because of dramatic strength deterioration of strength according to increasing replacing rate. In this study's result, regardless of differences in fine aggregates used, in order to get uniaxial compression strength in the scope exceeding criteria of minimum strength for applying to the field, the most reasonable combination was to mix replacing BFS with fineness of 6000 in 30%. For the CLMS mixing BFS and SS, in order to improve flow ability by securing quantity of minimum unit and to repress bleeding rate with securing uniaxial compress strength considering the field applicability, regardless of differences in fine aggregates used, to mix BFS over 6000 in 30% was most effective.

• Computers and Concrete
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• v.30 no.6
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• pp.393-407
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• 2022

Due to the enormous cement content, pozzolanic materials, and the use of different aggregates, sustainable controlled low-strength material (CLSM) has a higher material cost than conventional concrete and sustainable construction issues. However, by selecting appropriate materials and formulations, as well as cement and aggregate content, whitethorn costs can be reduced while having a positive environmental impact. This research explores the desire to optimize plastic properties and 28-day unconfined compressive strength (UCS) of CLSM containing powder content from unprocessed-fly ash (u-FA) and recycled fine aggregate (RFA). The mixtures' input parameters consist of water-to-cementitious material ratio (W/CM), fly ash-to-cementitious materials (FA/CM), and paste volume percentage (PV%), while flowability, bleeding, segregation index, and 28-day UCS were the desired responses. The central composite design (CCD) notion was used to produce twenty CLSM mixes and was experimentally validated using MATLAB by an Artificial Neural Network (ANN). Variance analysis (ANOVA) was used for the determination of statistical models. Results revealed that the plastic properties of CLSM improve with the FA/CM rise when the strength declines for 28 days-with an increase in FA/CM, the diameter of the flowability and bleeding decreased. Meanwhile, the u-FA's rise strengthens the CLSM's segregation resistance and raises its strength over 28 days. Using calcareous powder as a substitute for cement has a detrimental effect on bleeding, and 28-day UCS increases segregation resistance. The response surface method (RSM) can establish high correlations between responses and the constituent materials of sustainable CLSM, and the optimal values of variables can be measured to achieve the desired response properties.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.159-160
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• 2017

Recently, researches on controlled low strength materials using coal ashes have been actively conducted in Korea. Controlled Low Strength Material by using a large amount of Coal Ashes, which is a by-product of the industry, will solve the environmental problems caused by coal ash as well as economic formulation. In this paper, the compressive strength and flow of the CLSM binder were investigated in order to select the optimum mixing ratio.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.91-96
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• 2011

The design, construction and management of underground facilities as infrastructure of nation should be properly carried out. One of reasons for underground facilitie's failure is a non-proper construction of backfill materials. This is common for circular underground pipes. A non-proper compaction is the cause of settlement and decrease of performance of underground facilities. The use of controlled low strength materials is an alternative to reduce the couple of failure problems. The flowability, self-cementation, and non-compaction are the major advantages to use the controlled low strength materials. In this research, couple of recycled materials, such as in-situ soil, water-treatment sludge, and crumb rubbers, were adopted. The basic properties of each materials were determined according to KS or ASTM. Also, couple of laboratory tests were carried out to get the design parameters for geotechnical and roadway area.

• Journal of the Korean Geotechnical Society
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• v.28 no.12
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• pp.27-39
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• 2012

This paper presented the strength and environmental characteristics of reclaimed-ground filled with controlled low-strength materials (CLSM) made of coal ash, small amounts of cement, and water in a reclamation site and evaluated the possibility of the use of coal ash on reclamation materials for beneficial use. Three-month period of SPT, CPT, environmental effects evaluation etc. were conducted. N values and cone resistances in ground filled with CLSM were greater than or similar to those in dredging sand. In case of land filled with coal ash except cement these values were lower than those in dredging sand. The results of soil and seawater pollution were lower than test criteria without high pH. Also the values of PH test were measured between pH 5.0~9.0, the criteria of industrial water in the Law for the Underground Water of Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.3C
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• pp.95-104
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• 2012

Due to current interest in creation of urban space and urban landscape, more emphasis has been placed on underground space development. With increasing number of underground power cables and its importance, a study of backfill materials for pipe is now imperative. Backfill materials require outstanding thermal characteristics since breakdown of cable insulation can be caused if heat generated from transmission of underground power cables had not been effectively discharged through backfill materials. Also, coal ash, which are industrial by-products, is being produced in high volume every year. Among them, ponded ash (PA) is not recycled and instead, mostly buried. Therefore in this study, thermal conductivity test based on mixture ratio (PA, ponded ash : FA, fly ash) was performed to evaluate the thermal conductivity characteristics of CLSM (controlled low strength materials) with coal ash. The results indicate that the mixture ratio (PA, ponded ash : FA, fly ash) of 80:20, water contents of 28~30%, and cement contents of 7-11% showed the highest conductivity at 0.796~0.884W/mK and thus, considered optimal in terms of recycling ponded ash (PA) as well as for maximizing utilization as backfill materials for pipe in underground.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09b
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• pp.32-37
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• 2010

Recently, the land area for many people has been limited because of industrialization and modernization in Korea. The large-scale constructions like the reclamation development projects have been progressed to resolve this problem mentioned above. Therefore, as many of the usefulconstruction materials as possible are needed to perform the large-scale construction projects. Many studies for the utilization of pond ash which has a similar characteristic of sand have been conducted and there has been often occurred many structural problems on roadbed in winter. Therefore, the characteristics of the freezing and thawing for Controlled Low-Strength Material (CLSM) using pond ash were analyzed and evaluated by unconfined compressive strength test in this study. As a result of this study, it was confirmed that new CLSM using pond ash with cement (8.2% by weight)was able to stand for the freezing and thawing behavior.

• Resources Recycling
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• v.26 no.3
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• pp.32-38
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• 2017

For the massive recycling of mine tailings, which are an inorganic by-product of mining process, in the field of civil engineering, pretreatments to extract heavy metals are required. This study focuses on the use of pre-treated tailings as substitute fillers for controlled low-strength material (CLSM). As a comparative study, untreated tailing, microwave-treated tailing and magnetic separated with microwaved tailing were used in this study. Cement contents amounting to 10%, 20% and 30% by the weight of the tailings were designed. Both compressive strength and flowability for all types of mixture were satisfied with the requirements of the American Concrete Institute (ACI) Committee 229, i.e., 0.3-8.3 MPa of compressive strength and longer than 200 mm flowability. Furthermore, all mixtures showed settlements less than 1% by volume of the mix.