• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.3
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• pp.71-78
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• 2009

Pipe section of bending part at the arch type pipe-house showed an ellipse with oblateness of 0.076 on the average. Flexural rigidity of bending part decreased by average 6.3% than that of an original round shape section. The deflection of arch type pipe-house measured by model experiments showed much bigger than the result of structural analysis. In case of arch type pipe-house, we supposed that the decrease of flexural rigidity for the bending part of pipes had an effect on deflection of roof under the working load. This effect should be considered in the structural analysis. Bending resistance of gable type pipe-house used a prefabricated connector which developed in this study showed about $1.5{\sim}1.8$ times stronger than that of the existing arch type or gable type processed bending. Therefore, we supposed that the gable-roofed prefabricated pipe-house is safer than arch type or bent gable type in case of heavy snowfall. According to house scales and section properties of steel pipe in use, safe snow depths and rafter intervals were presented for design of gable-roofed prefabricated pipe-house. Their standards were established in the range of the durable models recommended by RDA, and the comparative examinations were conducted by means of structural analysis. It was evaluated that the developed greenhouse model had a high applicability in the field.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.591-600
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• 2005

There are many cross tunnelling methods such as NTR, TRCM, Messer Shield, Front Jacking, and Pipe Roof Method. The advantages of adopting RPS(roof panel shield) method in crossing tunnel construction with comparing other existing cross tunnelling method are needed a little space and easy to change the direction of cutting shoe during the construction of pipe roof. The numerical analysis of RPS was performed for the application in the crossing tunnel under railroad. The earth pressure distribution and settlement were predicted when the RPS method was applied during the excavation for crossing railroad tunnel construction.

• Structural Engineering and Mechanics
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• v.33 no.4
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• pp.503-527
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• 2009

This paper presents experimental results on the behaviour and ultimate load of fifteen pipes and six roof panels made of ferrocement. Additional results from three roof panels, carried out by others, are also compared with this research results. OPC cement, natural sand and galvanised iron wire mesh were used for the construction of 20 mm thick specimens. The pipe length was 2 m and roof panel length was 2.1 m. The main variables studied were the number of wire mesh layers which were 1, 2, 3, 4 and 6 layers, the inner pipe diameter which were 105, 210 and 315 mm, cross sectional shape of the panel which were channel and box sections and the depth of the edge beam which were 95 mm and 50 mm. All specimens were simply supported and tested for pure bending with test span of 600 mm at mid-span. Tests revealed that increasing the number of wire mesh layers increases the flexural strength and stiffness. Increasing the pipe diameter or depth of edge beam of the panel increases the cracking and ultimate moments. The change in the pipe diameter led to larger effect on ultimate moment than the effect of change in the number of wire mesh layers. The box section showed behaviour and strength similar to that of the channel with same depth and number of wire mesh layers.

• Journal of the Korean Society for Railway
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• v.9 no.2 s.33
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• pp.174-179
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• 2006

Recently, the crossing tunnel has been constructed frequently to connect the separated area by highway and railroad. The construction of crossing tunnel must be progressed while maintaining the existing traffic of the highway as well as railroad. There are many cross funnelling methods such as NTR, TRCM, Messer Shield, Front Jacking, and Pipe Roof Method. The advantages of adopting RPS(Roof Panel Shield) method in crossing tunnel construction with comparing other existing cross funnelling methods are needed a little volume of concrete and easy to change the direction of cutting shoe during the construction of pipe roof, The 3-dimensional numerical analysis of RPS to consider the arching effect was performed for the application in the crossing tunnel under railroad. The earth pressure distribution and settlement were predicted when the RPS method was applied during the excavation for crossing railroad tunnel construction.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.454-461
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• 2005

There are many cross tunnelling methods such as NTR, TRCM, Messer Shield, Front Jacking, and Pipe Roof Method. The advantages of adopting RPS(Roof Panel Shield) method in crossing tunnel construction with comparing other existing cross tunnelling method are needed a little space and easy to change the direction of cutting shoe during the construction of pipe roof. The 3-dimensional numerical analysis of RPS was performed for the application in the crossing tunnel under railroad. The earth pressure distribution and settlement were predicted when the RPS method was applied during the excavation for crossing railroad tunnel construction.

• The magazine of the Korean Society for Advanced Composite Structures
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• v.5 no.2
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• pp.26-31
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• 2014

This invention is purposed to provide an innovative solution for the inside of roof structures, which is cultural assets. The Asian old houses generally have several layered roofs on top of the structures. If a fire has started inside of the roof, it is hard to be extinguished before eliminating all the upper layers of the roof. This invention provides pre constructed embedded pipes, which is flammable and easy to be dissolved by the fire. The material of pipe is composed of rubbers, of which the combustion point is so low that the extinguishing of initial fire is possible without additional fire service. The inside of pipe is filled with halon gas. If the filled gas is consumed after ignited by fire, additional fire extinguishing water is supplied. If the flexible pipes are totally combusted by a big fire, the sprinkler at the end of inflexible pipe will work continuously, which is located between flexible and inflexible pipes. The extinguishing pipe network is suggested as dividing whole roof as multiple sections for a swift fire extinguishing in case of intentional or natural fire attack to our invaluable cultural assets.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.3
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• pp.225-231
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• 2001

When building tunnels beneath riverbeds where very large quantities of groundwater inflow exist, added to high water head the soil supporting conditions are very poor because the soil consists of sand and silt, etc. It is necessary to have grouting and mini pipe roof installed in the region for ground reinforcement to decrease permeability. According to this result of horizontal boring and laboratory soil testing, ground reinforcement was achieved by L.W grouting for range of 3.0 times the tunnel radius, to increase stability of the tunnel we used the ling-cut method, 0.8m for one step excavation, shotcrete with 25cm thick, steel lib with H-$125{\times}125$. and a temporary shotcrete invert 20cm thick was installed to prevent deformation of the tunnel.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.664-670
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• 2010

The study on mechanical behavior of the structure at the site includes experimental method and numerical analysis method. Experimental method is categorized into true-scale test and laboratory model test. A laboratory model test is to monitor the failure mechanism with a model simulated similar with a real ground so as to identify the quantitative result, while a true-scale model test is the approach which enables to identify the potential problems that may occur with a simulated construction situation similar with a real site circumstance. Thus this study was intended to carry out the experimental test of non open-cut excavation by pipe roof method which is mostly common in domestic sites. as well as was aimed at identifying the ground behavior occurred during pipe penetration using laboratory model test. Appropriate reduced-scale model was selected, taking into account of domestic geological characteristics and operation characteristics of traditional and high-speed rail trains and the qualitative evaluation of displacement was carried out based on a certain ground loss volume depending on excavation after categorizing trackbed settlement pattern by depth of top soil.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.776-781
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• 2001

Internal pipes technology for LNG Storage tank developed because of the perceived safety risk of having an opening near the base of the shell. This is because the shell at this point is the most highly stressed component of the primary containment. other, secondary, problems arise because the movement of the tank in this region is also at a maximum. This requires the use of bellows either in the interspace or on the outside of the outer tank. Therefore the internal pipe, through the roof, solves these problems. The loading conditions calculated from design concept are then used to perform a pipe stress analysis. As well as determining the stresses in the internal pipe and checking against allowable stress, it determines the reaction forces at the support positions.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.655-660
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• 2005

Recently, the crossing tunnel has been constructed to maintain the operation highway as well as railroad. The advantages of adopting RPS method in crossing tunnel construction are needed a little space and easy to change the direction of cutting shoe during the construction of pipe roof. The numerical analysis of RPS was performed for the application in the crossing tunnel under railroad. The earth pressure distribution and settlement were predicted when the RPS method was applied during the excavation for crossing tunnel construction.