• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.3
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• pp.239-247
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• 2005

A new railway line of about 17km length was planned between Dongbaeksan and the neighboring town Dokye to improve the existing decrepit railway system. New line about 17km of the distance will almost be in circular alignment tunnels owing to the difference of elevation about 380m. Since the geology of the area is rather unusual compared to the normal in South Korea, extensive geological investigations have been carried out to prepare geological maps and profiles along the planned tunnel routes. The tunnel will almost be in sedimentary rock formations, such as limestone, sandstone, shale, coal etc and be near abandoned mines Various rock formations have the complicated, alter ed those rocks, but are well developed with laminated formations. Each rock formations have been classified using the Q-system and the cost of tunnel excavation, support has been estimated and compared for three alternative routes in the design stage. Based on these estimates, the final route of t he railway line was chosen.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.10
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• pp.1449-1457
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• 2008

This experiment was carried out to evaluate the carcass characteristics, chemical composition and fatty acid profile of the Longissimus muscle (LM) of three cattle genetic groups (Purunã, PUR, 11; 1/2 Purunã vs. 1/2 British, PUB, 6 and 1/2 Charolais vs. 1/2 Caracu, CHC, 10) finished in pasture systems. The field work took place at the Lapa Research Farm of the Agronomic Institute of Paraná, in the city of Lapa, south Brazil. The animals were fed during the winter with corn silage, cottonseed meal, cracked corn, urea, limestone and mineral salts as sources of protein, as well as an energy supplement, in pasture systems of Brachiaria decumbens Stapf. The animal groups were slaughtered at 20 months of age, at 50122.6 kg live weight. CHC bulls had higher (p<0.05) final weight than PUR and PUB bulls. Hot carcass weight was similar (p>0.10) between PUR and PUB. Hot carcass dressing percentage was higher (p<0.05) for PUB bulls than for PUR and CHC bulls. On the other hand, hot carcass dressing percentage was similar (p>0.05) between PUR and CHC bulls. Fat thickness was similar (p>0.10) among all genetic groups. However, the Longissimus area of CHC bulls was greater (p<0.05) than in PUR and PUB genetic groups. The genetic groups did not affect (p>0.10) the marbling of Longissimus. There was no observed difference (p>0.10) in moisture, ash, crude protein and total cholesterol contents among the three genetic groups. On the other hand, the total lipid percentage was higher (p<0.05) for the PUB genetic group in comparison with PUR and CHC. CLA percentage was highest for PUR animals. However, total CLA amounts were not altered by the different genetic groups.

• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.44-49
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• 2007

It is difficult to obtain high-resolution images by 3D gravity inversion, because the problem is extremely underdetermined - there are too many model parameters. In order to reduce the number of model parameters we propose a 3D gravity inversion scheme utilising Euler deconvolution as a priori information. The essential point of this scheme is the reduction of the nonuniqueness of solutions by restricting the inversion space with the help of Euler deconvolution. We carry out a systematic exploration of the growing body process, but only in the restricted space within a certain radius of the Euler solutions. We have tested our method with synthetic gravity data, and also applied it to a real dataset, to delineate underground cavities in a limestone area. We found that we obtained a more reasonable subsurface density image by means of this combination between the Euler solution and the inversion process.

• Advances in concrete construction
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• v.9 no.2
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• pp.217-225
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• 2020

The recovery of waste proves a solution with two impacts: the environmental impact by the reduction of pollution and the gain of the occupied space by this waste, and the economic impact by the use of these lasts in the building and in the area of public works. The present research consists in recovering a waste marble (thrown powder exposed to the different meteorological phenomena) generated by the quarry marble of Fil-fila, located at the east side of Skikda in the north-east of Algeria, and add it, as sand in the composition of sand concrete. To carry out this research, we analyzed the evolution brought by the substitution of ordinary sand by marble waste sand, with 25%, 50%, 75% and 100% on the properties in the fresh state (density, workability and air content) and in the cured state (compressive strength, tensile strength, surface hardness and sound velocity). For durability we tested water absorption by immersion and chloride penetration. The results obtained are compared with control samples of 0% of substitution rate. In order to have a good filling of the voids in the granular skeleton; we added a quantity of limestone recycled fines from the quarries and for a good workability a super-plasticizing additive. The results showed that the partial substitution modified both the fresh and the hardened characteristics of the tested concretes, the durability parameters also improved.

• International Journal of Highway Engineering
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• v.19 no.5
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• pp.77-88
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• 2017

PURPOSES : It is necessary to clarify the rheological properties of cement paste as a basic research in the development of mechanistic concrete mix design. The rheological properties of cement paste with different binder types, mix propositions, and with/without high range water reducers have been analyzed. METHODS : In this study, ordinary Portland cement, fly-ash, blast furnace slag, silica fume, and limestone powder were used as binders. The range of water-binder ratio was 0.3-0.5, and a total of 30 different mixes have been tested. The slump flow test, V-funnel test, and Dynamic Shear Rheometer (DSR) test were performed to analyze the rheological properties of cement paste. RESULTS : As a result of the slump flow test, it was found that the composition ratio of the binder contents greatly affected the paste flow when the high range water reducers were added. The results of V-funnel test showed that when the water-binder ratio was decreased without high range water reducers, the binder composition ratio had a large effect on the passing time of the V-funnel tester, but with high range water reducers the impact of the binder composition ratio was decreased. The slump flow and V-funnel have a certain relationship with the rheological factors (yield stress and plastic viscosity), but the correlation was not significant. Finally, we proposed the M-value considering the density and specific surface area of the binder. The correlation between rheological factors and M-value were better demonstrated than experimental values, but there is still a limit to predict the rheological factor in general mix design. CONCLUSIONS :In this study, the rheological properties of cement paste were analyzed. The binder type, composition ratio of binder, and with/without high range water reducers have combined to provide the complex effects on the rheological properties of cement paste. The correlation between the proposed M-value and rheological factor was found to be better than experimental results, but needs to be improved in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.4
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• pp.598-604
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• 2009

This work was carried out to study the carcass characteristics, the chemical composition and the fatty acid profile in Longissimus muscle (LM) of bull breeds Nellore, NEL (11), Caracu, CAR (12) and Holstein-Friesian, HFR (12) finished in a feedlot. The bulls were fed twice a day with corn silage, cotton meal, cracked corn, urea, limestone and mineral salt. NEL and CAR bulls had similar (p>0.05) final weight and hot carcass weight. However, NEL and CAR bulls had higher (p<0.05) final weight and hot carcass weight than HFR bulls. Carcass hot dressing, carcass conformation, cushion thickness, Longissimus muscle area and texture were similar (p>0.05) among NEL, CAR and HFR bulls. NEL and HFR bulls had higher (p<0.05) carcass length in comparison to the CAR breed. Nellore breed had higher (p<0.05) leg length in comparison to CAR and HFR breeds. Leg length was similar (p>0.05) between CAR and HFR breeds. Thickness fat, color and marbling score were lower (p<0.05) in NEL breed in comparison to CAR and HFR breeds. LM of NEL bulls had higher (p<0.05) meat moisture content in comparison to CAR and HFR bulls. In contrast, lipid content was lower (p<0.10) in HFR bulls. LM ash and crude protein contents were similar (p>0.05) among breeds. Saturated fatty acids (SFA) were higher (p<0.10) in HFR animals. Monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), n-6, n-3 and PUFA/SFA ratio were similar (p>0.05) among the different breeds. N-6/n-3 ratio was higher (p<0.05) in CAR animals.

• Tunnel and Underground Space
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• v.25 no.6
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• pp.527-533
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• 2015

This study performed an on-site demonstration of the topographic surveying technique at a large-scale open-pit limestone mine in Korea using a fixed-wing unmanned aerial vehicle (UAV, Drone, SenseFly eBee). 288 sheets of aerial photos were taken by an automatic flight for 30 minutes under conditions of 300 m altitude and 12 m/s speed. Except for 37 aerial photos in which no keypoint was detected, 251 aerial photos were utilized for data processing including correction and matching, then an orthomosaic image and digital surface model with 7 cm grid spacing could be generated. A comparison of the X, Y, Z-coordinates of 4 ground control points measured by differential global positioning system and those determined by fixed-wing UAV photogrammetry revealed that the root mean squared errors were around 15 cm. Because the fixed-wing UAV has relatively longer flight time and larger coverage area than rotary-wing UAVs, it can be effectively utilized in large-scale open-pit mines as a topographic surveying tool.

• The Journal of Engineering Geology
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• v.30 no.2
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• pp.175-184
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• 2020

In Korea, there are many regulations and cases for horizontal seismic coefficient to pseudo-static analysis of slope, but there are insufficient regulations and cases for vertical seismic coefficient. Therefore, geological investigation and laboratory tests were conducted to analyze the effect of the vertical seismic coefficient on slope stability, and pseudo-static analyses based on infinite slope stability analysis were performed by using those results. As a result, if the earthquake magnitude is less than M 5.0, the effect of the vertical seismic coefficient is not significant, and if the earthquake magnitude is more than M 6.0, the vertical seismic coefficient largely increases the unstable areas of Fs ≤ 1.1. These tendency is more distinct in rainfall condition than without rainfall condition.

• Journal of the Speleological Society of Korea
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• no.68
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• pp.99-120
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• 2005

It is a wrong decision to use only topographic and geological maps for the study of pediment morphology in Korea. For the study of pediment morphology it is necessary to survey the earth structure by field techniques. In Korea, pediments are mostly found in granite areas with hardrock cover. But, pediments also developed in gneiss areas and what is worse in limestone areas. So, all areas in Korea developed pediment morphology. Only in South Korea pediments show a direction from south to north or from west to east. They developed only in right angles to each other, either parallel or in right angles to the strike, depending on the bedrock structure. Pediments are found in two levels. The upper level pediments are correlated with the lower level erosion surface. Besides this pediments are found in Hoenggye-ri of the Taegwolryong area in a third level 800m above sea level. The pediments developed in basins, at the lower margins of steep slopes dividing three levels of erosion surfaces and around the residual mountains on the erosion surfaces. The first belong to the early stage of pedimentation, the second to the middle stage and the third to the last stage. Also, in Korea monadnock and residual mountain have developed the pediments are correlated the slope of the hinter mountains. Akagki states that the only pedimentation times have been times of arid climate and that they are dissected by gulley erosion with climatic change, but writer's study proves that pedimentation takes place with eustatic movement, reckless defore-station and convectional rain. These facts indicate that the landforms, geological character and process of erosional cycle of the pediments in Korea resemble much those in the Chugoku Mountains of south wertern Japan, but they are larger in scale than those in the Chugoku Mountains. In conclusion, while Akagki emphasizes the geological character and climatic change in pedimentation, the writer studies prove that eustatic movements, especially the sea level rise after the Wurm age are important factors for pedimentation. Besides this the author's studies allow a classification of gentle slopes.

• The Journal of Engineering Geology
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• v.24 no.1
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• pp.137-146
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• 2014

The geology of the study area which is located in Samkoe-dong, Dong-gu, Daejeon city comprises black slate, limestone, and pebble-bearing phyllitic rock as meta-sedimentary rocks; and biotite granite and quartz porphyry intrusions. Face mapping revealed sliding in three or four sites of contained coaly slate, where the dip of the foliation and other discontinuities is parallel to the surface slope. The cause of the slope sliding is this parallelism as well as the swelling of the coaly slate when wet. In contrast, the slop on the opposite side of the road is relatively stable because the dip of the foliation and other discontinuities are oblique or normal to the surface slope. To ensure slope stability, a cut-and-cover tunnel was designed and constructed for the new road.