• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.1
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• pp.99-111
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• 1999

The purpose of this study was to evaluate crystalline silica contents in airborne respirable dusts from various manufacturing industries and to compare analytical ability of two different methods of quantifying crystalline silica, X-ray diffraction(XRD) and Fourie transform infrared spectroscopy(FTIR). Various manufacturing industries with a history of having pneumoconiosis cases and also known to generate dusts containing crystalline silica were investigated. These industries include: ceramics, brick, concrete, and abrasive material etc. The personal respirable dust samples were collected using l0mm, Dorr-Oliver nylon cyclone equipped with 37mm, $5{\mu}m$ pore size. polyvinylchloride (PVC) filters as collection media. All samples were weighed before and after sampling and were pretreated according to the NIOSH sampling and analytical methods 7500, and 7602 for dust collection and quartz analysis. A total of 48 samples were collected from these industries. Initial analyses of these samples showed log-normal distributions for dust and quartz concentrations. Some results from ceramics and stone exceeded current Korean Occupational Exposure Limits. The average concentrations of personal respirable dust by cyclone were 0.43, 0.24, 0.26, 0.42, 0.53 and $0.29mg/m^3$ in ceramics, stone, concrete, glass, briquets, and others, respectively. A comparison of performance of two analytical methods for quantifying crystalline silica was performed using data from ceramics. The results showed that no significant difference was found between two methods for ceramics. The mean crystalline silica contents determined by XRD were 3.41 % of samples from briquets and 7.18 % from ceramics and were 2.58 % from concrete and 10.33 % from ceramics by FTIR. For crystalline silica analysis, two analytical techniques were highly correlated with $r^2=0.81$ from ceramics. Both cristobalite and tridymite were not detected by XRD and FTIR.

• Computers and Concrete
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• v.23 no.3
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• pp.189-201
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• 2019

Recent advances in the concrete technology are aiding in minimizing the use of conventional materials by substituting by-products of various industries and energy sources. A large amount of stone waste i.e., dust and slurry form both are being originated during natural stone processing and causing deadily effects on the environment. The disposal problem of stone waste can be resolved effectively by using waste in construction industries. In present work, Kota stone slurry powder, as a substitution of cement was used along with accelerators namely calcium nitrate and triethanolamine as additives, to study their impact on various properties of the concrete mixtures. Kota stone slurry powder (7.5%), calcium nitrate (1%) and triethanolamine (0.05%) were used separately as well in combination in different concrete mixtures. Mechanical Strength, modulus of elasticity and electrical resistivity of concrete specimens of different mix proportions under water curing were studied experimentally. The durability properties in terms of strength and electrical resistivity against sulphate and chloride solution attack at various curing ages were also studied experimentally. Results showed that accelerators and Kota stone slurry powder separately enhanced the mechanical strength and electrical resistivity; but, their combination decreased strength at all curing ages. The durability of concrete specimens was also affected under the exposure to chemical attack too. Kota stone slurry powder found to be the most effective material among all materials. Material characterization was also done to study the microstructural properties.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.44-50
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• 1997

Permeable polymer concrete can be applied to roads, sidewalks, river embankment, drain pipes, conduits, retaining walls, yards, parking lots, plazas, interlocking blocks, etc.. This study was to explore a possibility of using stone dust and heavy calcium carbonate as fillers for the permeable polymer concrete. Different mixing pro-portions were tried to find an optimum mixing proportion of the permeable polymer concrete. The tests were carried out at 20 f 1 t and 60 ${\pm}$ 2% relative humidity. At 7 days of curing, compressive, flexural and splitting tensile strengths and water permeability ranged between 209~246kgf/cm$^2$, 101 ~ l2lkgf/cm$^2$, 36~52kgf/cm$^2$ and 3.076 ~ 4.390L/cm$^3\;^2$/hr, respectively. It was concluded that the stone dust and heavy calcium carbonate could be used in the permeable polymer concrete.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.149-152
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• 2002

This study is performed to evaluate the properties of ECO-permeable polymer concrete with blast furnace slag powder and stone dust. The unit weight is in the range of $1,821kg/m^3{\sim}1,955kg/m^3$, the unit weights of those concrete are decreased $15%{\sim}20.8%$ than that of the normal cement concrete. The highest strength is achieved by ECO-permeable polymer concrete filled blast furnace slag powder 50% and stone dust 50%, it is increased 36% by compressive strength, 119% by tensile strength and 217% by bending strength than that of the normal cement concrete, respectively. The coefficient of permeability is in the range of $5.6{\times}10^{-2}cm/s{\sim}8.1{\times}10^{-2}cm/s$, and it is largely dependent upon the mix design.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.197-200
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• 2002

This study is performed to examine the non-destruction properties of the Hwangtoh mortar. The absorption ratio is in the range of $8.25%{\sim}18.16%$, it tend to increase with increase using the stone dust and Hwangtoh. The pulse velocity and dynamic modulus at the curing age 7 and 28days are in the range of $2,290m/s{\sim}4,140m/s,\;2,976m/s{\sim}4,219m/s\;and\;105{\times}10^3kgf/cm^2{\sim}293{\times}10^3kgf/cm^2,\;137{\times}10^3kgf/cm^2{\sim}318{\times}10^3kgf/cm^2$, respectively. They tend to decrease with increase using the stone dust and Hwangtoh.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.4883-4888
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• 2012

In materials science, one of the new concerns in the construction industry, it is well established that mineral dust from rocks (stones) has adverse effects on human health. For instance, it is suspected that some mineral dusts in particular leads to occupational diseases, including lung cancer. The present research concerned the relationship between cancer and those workers who work in Turkish construction industry and quarries and are exposed to silica mineral dust from natural stones. One focus was cancer prevention methods applied in-site. In mining and construction industry where stone dust is widely used, silicosis induced lung cancer is frequently seen. Cancer cases which are seen across the regions mostly affected by silica containing dust in Turkey were identified and a survey was conducted of the methods to protect workers in the construction industry from exposure to silica dust.

• Journal of the Korea Safety Management & Science
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• v.6 no.4
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• pp.171-181
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• 2004

A multi axis whetstone polishing system, which uses the flow system of the stone polishing machine head, has been developed. The test results show that the defect by line contact polishing does not occur in both ends of the stone and that it came to trim smoothly. In terms of the surface roughness, the corresponding index was decreased by 3.6 times, improving the polishing effect greatly. It decreased significantly the dust and noise with the wet polishing. The factors of the duty evasion at production site can thus be solved with the work environment improvement against the polishing process of the stone industry and work intensive reduction.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.165-170
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• 2004

It used the flow system of the stone polishing machine head and it developed a multi axis whetstone polishing system. With the result, the defect by line contact polishing does not occur in both ends of the stone, and it came to trim smoothly. As the index of the surface roughness decreased to 3.6 times, the polishing effect improved greatly. It decreased greatly the dust and a noise with the wet polishing, and the factors of the duty evasion at production site were solved with the work environment improvement against the polishing process of the stone industry and work intensive reduction.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.61-69
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• 1996

This study was performed to evaluate the engineering properties of permeable polymer concrete with fillers and unsaturated polyester resin. The following conclusions were drawn. 1. The highest strength was achieved by stone dust filled permeable polymer concrete, it was increased 17% by compressive, 148% by tensile and 188% by bending strength than that of the normal cement concrete, respectively. 2. The static modulus of elasticity was in the range of $1.17{\times}10^5{\sim}1.32{\times}10^5kg/cm^2$, which was approximately 53~56% of that of the normal cement concrete. Stone dust filled permeable polymer concrete was showed relatively higher elastic modulus. The poisson's number of permeable polymer concrete was less than that of the normal cement concrete. 3. The dynamic modulus of elasticity was in the range of $1.3{\times}10^5{\sim}1.5{\times}10^5kg/cm^2$, which was approximately less compared to that of the normal cement concrete. Stone dust filled permeable polymer concrete was showed higher dynamic modulus. The dynamic modulus of elasticity were increased approximately 10~13% than that of the static modulus. 4. The water permeability was in the range of $3.076{\sim}4.390{\ell}/cm^2/h$, and it was largely dependent upon the mix design. These concrete can be used to the structures which need water permeability. 5. The compressive strength, tensile strength, bending strength and elastic modulus were largely showed with the decrease of water permeability.

• Resources Recycling
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• v.3 no.3
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• pp.12-20
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• 1994

Difficulties lies on using the dust from iron making process as a raw material for sintering process mainly because of high amount of Zn or alkali content and its ultra fine characteristics. To eliminate these toxic influence, new fluxing materials were tested and could get a very successful results. This fluxing materials, Calcium-ferrite of magnesio-ferrite were made from various waste materials such as lime stone sludge, bag filter dust, waste EP dust and dolomite sludge by simple way of pre-sintering. Sintering behavior as a fluxing materials was revealed to be good in any aspects and new concept of total recycling system could be established.