• Journal of ILASS-Korea
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• v.19 no.3
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• pp.136-141
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• 2014

This study reports numerically the characteristics of dust scattering around the coal storage pile yards, substantially affected by the windbreak wall height. The dust scattering is closely associated with the frictional effect of wind flows as well as the pressure variation that consequently affect the dust particle behavior. In the present study, with the use of the commercial code of FLUENT, the distribution of wind velocity and pressure are predicted around coal storage pile yard for four different heights of the wind break wall. From the results, it was found that for the case 1 with the outer windbreak wall height of 3 m and inner windbreak wall height of 6 m, the amount of scattering dust for a year was estimated to be 1451 kg, whereas for the case 4 where a height of outer windbreak wall is 10 m and a height of inner windbreak wall is 16 m, the amount of scattering dust for a year was 358 kg. It shows that the dust scattering can be reduced by 75%, indicating important role of windbreak wall height on particle scattering. The numerical results would be useful in decision of the appropriate height of windbreak wall for decreasing the amount of scattering dust under various environmental conditions.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.1
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• pp.93-101
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• 2010

When doing underground excavation works for the purpose of constructing large underground structures for a building in the limited space in downtown area, the stability of the adjacent ground must be top priority, and to accomplish this, it is essential to review the retaining wall construction carefully. H-Pile, which has been mainly used as a stress-carrying material in temporary earth-retaining structures, is most likely to be abandoned after completion of the works for the basement exterior wall in relation to contiguous bored piles, so it will result in a waste of material. To improve this situation, Basement Composite Wall where H-Pile and basement wall are compounded, has been developed. This wall is being used most frequently in many local construction sites. In this study, five specimens are made in order to evaluate the shear resistance of the basement composite wall and tested. Test parameter is the composition ratio and wall thickness according to shear connectors. Test result shows that the shear strength is improved when the composite ratio is increased but the magnitude is not much. A formula, which considers the contribution of concrete, web of H-pile as well as flange' effect in calculation of shear strength of composite basement wall, is suggested and used to calculation of the strength of specimens. It is found that there is a good co-relation between test result and the calculated one by the formula.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.3
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• pp.33-42
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• 2005

The bearing methods using pile of steel itself or reinforced concrete has been applying which in excavated depth was not deep. Also, the retaining wall as resisting structure to lateral force has taken weakness that the cure periods of concreted is long. Recently, with the material cost of steel, the application of cement is more increasing trend. In this study, the design methods of earth retaining and retention wall within the pre-casted concrete pile, PHC(Pretentioned spun High strength Concrete piles), was proposed which in the ground condition of excavated depth was not deep. The typical ground conditions, cohesive and non-cohesive soil, was considered as follows; soil strength as internal friction angle and UU(Undrained Unconsolidation triaxial test) strength, soil reaction and stabilization of structures. The application of design methods could be confirmed through the comparing and analyzing between measured data and utility software for the design.

• Journal of the Korean GEO-environmental Society
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• v.3 no.3
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• pp.37-44
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• 2002

Sheet piles are often used to build continuous walls for the waterfront structures, and also used for some temporary structures, such as the braced cuts. Sheet pile walls may be divided into two basic categories that is cantilever and anchored. Stock(1992) developed an expedient format for determining the depth, maximum bending moment and anchor force of sheet pile wall for cantilever and free earth supported anchored wall. But, that is useful only in case that water table exists above the dredge line. In this study, a simplified formulae was developed for the design of the anchored free earth supported sheet pile wall both in sand and clay by solving the derived equations and regression analysis. It can be used whether the ground water table is above or under the dredge line.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.3
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• pp.19-25
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• 2019

The purpose of this study was to evaluate bending performance of concrete filled soldier pile for temporary retaining wall. Structural performance tests were conducted on total number of four specimens. Each specimen had a unique characteristics with combination of the following variables, existence of reinforcing bar and locations of reinforcing steel plates. The results of this study were as follows; concrete filled steel tubes with being reinforced bar and flange rather than non-bar showed better performance. Higher yield, tensile strength and sufficient plastic strain were archived and maximum moment observed in experiments exceeded theoretical maximum moment in both allowable stress design and limit state design at all specimens.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.20-27
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• 2014

In the construction site, various earth retaining systems are developed and applied to maintain stability of excavated area and structures. Among the methods, the underground continuous wall and the column-type diaphragm wall methods are especially used in construction site nearby buildings or roads. However, these methods have some disadvantages such as the difficulty of quality control and long curing time because these methods need to cast fresh concrete at the construction site. In addition, these methods are usually applied to the site for the temporary purpose. In this paper, we suggest precast hollow prestressed concrete pile for continuous pile wall system. To investigate the structural behavior of suggested pile, which is the main member of the suggested system, tests pertaining to the structural behavior and prestressing force applied in the pile are conducted. From the test results, it was found that the prestressing force measured is sufficient compared with the value obtained by the design equation and the cracking moment measured is 34% higher than the design value. In addition to the above, this precast hollow prestressed concrete pile has an additional safety margin that the maximum moment is 59.2% higher than the cracking moment which is one of the serviceability limits for the design of the system.

• Geomechanics and Engineering
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• v.14 no.6
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• pp.601-614
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• 2018

This study presents structural and parametric analyses on the behavior of an integrated and pile-bent abutment with mechanically stabilized earth wall (IPM) bridge. The IPM bridge is an integral abutment bridge (IAB) with partially protruded piles, which excludes earth pressure by means of a mechanically stabilized earth wall developed by the authors. The results of the analysis indicate that the IPM bridge, as any other IAB, is influenced to a large extent by temperature and time-dependent loads. When these loads are applied, the stress on a pile in the IPM bridge decreases as the displacement of the pile top increases, because the piles protrude from the ground surface and no soil reaction is generated on the protruded pile. Because the length of an IAB is restricted by the forces acting on its piles, the IPM bridge is an effective alternative to extend its length.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.754-759
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• 2008

Recently, the construction of buildings and large bridges has been increasing rapidly causing foundation structure growing larger then before, especially in the use of large size cast-in-place piles. Barrette Pile will usually be used at the site where diaphragm wall is the retaining wall to save time and cost in mobilization of equipments. This study uses bi-directional loading test data obtained from two different sites to observe the bearing capacity and displacement characteristics of barrette pile. Numerical analysis of the test is done by using commercial 3D computer program and the interface effect and capacity of the pile as well as displacement characteristics of the pile is verified.

• Journal of the Korean Geotechnical Society
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• v.33 no.2
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• pp.27-34
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• 2017

Various earth retaining wall methods were used on the domestic construction sites and a cast in place pile (C.I.P) method was mostly applied at deep excavation. Because of a lot of shortcomings in the C.I.P method, a new method using PHC-W earth retaining wall was developed. The earth retaining wall method using PHC-W piles has a lot of advantages including that it is safer than other earth retaining wall methods due to uniform quality and high rigidity. PHC-W was designed to effectively resist lateral earth pressure by alternating cross section of PHC pile. And increment of bending moment and shear strength were verified through KS F 4306 tests, and were increased by 42% and 98% more than KS standards.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.3
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• pp.176-184
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• 2007

The objective of this paper is to suggest a nonlinear analysis process to predict the structural behavior and strength of composite basement wall member combined with H-Pile. Therefore, the structural behavior of composite basement wall is studied and the special nonlinear characteristics of each elements such as H-Pile, concrete wall, and shear connectors are idealized using ATENA program. Finally, the result is compared with previous test result. Research result shows that there is a good co-relation between analysis and test results even if analysis result has little bit higher initial stiffness than test result. It can be concluded that the nonlinear behavior of composite basement wall is suitably predicted by using the contact element model in ATENA program as shear connector element.