• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.569-575
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• 2007

The repair of concrete surfaces does not normally take into account structural tolerance for longer service lift and better capabilities of concrete structures. In particular, the repair of surface spelling completes as mortar is applied, which does not display additional structural performances. The use of crimped wire mesh for better construction and fracture resistance, however, expects to have some reinforcement effects. Particularly, it is also expected that the repair of bottom part in structures built between bridges like irrigation structures results in the increase of flexural resistance. Therefore, this study is intended to perform the repair using crimp wire mesh and examine strength depending on the repair section and depth. For this, a slab with 150 mm in depth, 3,000 mm in length and 600 mm in width and total 8 objects to experiment such as upper part, upper whole, bottom part, bottom whole and crimp wire mesh reinforced are manufactured to perform flexural performance. The results of the analysis show that yield strength and failure load increase as the depth of repair materials in the experiment reinforced with crimp wire mesh get bigger. In the same condition, repair of bottom part is able to increase internal force of bending force. Besides, the results show that partial repair of structures under bending force cannot produce flexural performance. Consequently, the repair method with crimp wire mesh results in the increase of flexural resistance.

• Journal of Biosystems Engineering
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• v.30 no.4 s.111
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• pp.195-201
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• 2005

The output of Stirling engine is influenced by the regenerator effectiveness. The regenerator effectiveness is influenced by heat transfer and flow friction loss of the regenerator matrix. In this paper, in order to provide a basic data for the design of regenerator matrix, characteristics of heat transfer and flow friction loss were investigated by a packed method of matrix in the oscillating flow as the same condition of operation in a Stirling engine. As matrices, several kinds of combined wire screen meshes were used. The results are summarized as follows; The packed meshes with high mesh no. in the side of heater part of regenerator showed effective than the packed meshes with low mesh no. in the side of cooler part of regenerator. The temperature difference and pressure drop of the regenerator were not made by the specific surface area of wire screen meshes but by the minimum free-flow area to the total frontal area. Among the No. 150 single screen meshes, 200-60 combined meshes, the 200-150-100 combined meshes showed the highest in effectiveness.

• Journal of the Korean Society of Safety
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• v.26 no.6
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• pp.45-53
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• 2011

This study was performed to develop repair and reinforcing materials in sewage drain pipe by using 40% of CAC(Calcium Aluminate Cement) and 4% of Polymer Powder. Regarding reinforcing materials to enhance load-bearing capacity, polyester textile and wire mesh were adopted and then they were evaluated by the measurement of deflection and Stress-strain Relationship. Two types of drain pipe made by concrete and PE were considered as plain specimens and then loading test were performed after repaired by CAC mortar impregnated reinforcing materials. As the test results of the load-bearing test on both drain pipe, there was higher load-bearing capacity on the specimen adopted wire mesh but debonding of repair mortar was found due to stiffness of wire mesh. By the way, repair system using CAC mortar impregnated polyster textile without wire mesh showed satisfactory results including bonding and load-bearing capacity regardless substrate, so this repair system using by mixture of CAC mortar and polyster textile is suggested as the reasonable repairing method within this experimental scope.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.1
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• pp.17-25
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• 2013

The mechanical properties appeared at the concrete mixed with Polypropylene fiber($1kg/m^3$, $3kg/m^3$, $5kg/m^3$) are compared with normal concrete and wire mesh one and evaluated. Achieved slump test to search effect that PP fiber gets to workability, even if the mixing amount of fiber increases, confirmed that slump value is no change almost. The no difference can be caused by hard mixture, but because of the big softness of fiber there is no effect greatly up to PP fiber mixing amount $5kg/m^3$ even with soft mixture. Compressive strengths and flexural strengths of the concretes with PP fiber and without the fiber are appeared almost alike. If examine load resistance ability by PP fiber mixing amount increase, it could know that the increase of fiber mixing amount improves load resistance ability and the toughness index is increased. While normal concrete is broken at the same time with crack, fiber mixed concrete stand in flexure load continuously after crack occurrence. In compare with wire mesh embeded concrete, wire mesh mixed concrete stands in some degree in flexure load by wire mesh crack occurrence and the test piece was broken at the same time. But, it could know that the PP fiber mixed concrete resist continuously to flexure load in bigger displacement.

• 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.

• International Journal of Safety
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• v.8 no.2
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• pp.20-25
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• 2009

In this study, an experiment in the field was performed to analyze the mechanical properties and the influence of steel fiber and silica fume on the rebound ratios of shotcrete. The experimental parameters which are the reinforcing methods (steel fiber, wire mesh), steel fiber contents (0.0%, 0.5%, 0.75%, 1.0%), silica fume contents (0.0%, 10.0%), layer thickness (60 mm, 80 mm, 100 mm), and the placing parts (sidewall, shoulder, crown) were chosen. From the mechanical test, it was found that the flexural strength and toughness is significantly improved by the steel fiber and/or silica fume. According to the results for the side wall in this test, the larger the fiber contents are in case of steel fiber reinforced shotcrete, the less the rebound ratios are within the range of 20-35%, compared to the wire mesh reinforced shotcrte. And also, the reduced rebound ratios were very larger in using steel fiber reinforced shotcrete with silica fume content of 10%, and these results are true of the shoulder and the crown. respectively.

• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.349-352
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• 2011

본 연구를 통해 개발하고자 하는 Wire-Mesh Type Mist Eliminator는 탄화수소(Hydrocarbon)를 취급하는 석유화학 공정 내에서 Vapor 중에 존재하는 $10{\mu}m$ 이하크기의 미세한 액체 Mist를 분리하는데 사용되는 화학 공정플랜트 요소부품이다. 석유화학 공정에서 발생되는 $5{\mu}m$이하의 크기를 가지는 액체 Mist를 제거하기 위해서는 Stainless와 Polypropylene 재질이 혼합된 새로운 WMT Mist Eliminator 국산화 제품개발 시급하다. 실험을 통해 확보한 인자를 바탕으로 제작된 시제품의 분석결과 석유 화학공정에 이용이 가능한 것을 확인하고 성능이 우수함을 알 수 있었다.

• Advances in concrete construction
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• v.8 no.2
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• pp.91-100
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• 2019

In this paper three damaged exterior RC beam-column joints made of recycled aggregate concrete (RAC) were repaired. The aim of the study was to restore back the lost capacity of the beam-column joint to the original state or more. A relatively cheap material locally available galvanized steel welded wire mesh (GSWWM) of grid size 25 mm was used to confine the damaged region and then jacketed with cement mortar. Repaired specimens were also subjected to similar cyclic displacement as those of unrepaired specimens. Seismic parameters such as load carrying capacity, ductility, energy dissipation, stiffness degradation etc. were analyzed. Results show that repaired specimens exhibited better seismic performance and hence the adopted repairing strategies could be considered as satisfactory. These findings would be helpful to the field engineers to adopt a suitable rapid and cost efficient repairing technique for restoring the damaged frame structural joints for post earthquake usage.

• Structural Engineering and Mechanics
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• v.60 no.6
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• pp.979-999
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• 2016

Stainless steel wire mesh (SSWM) is an alternative material for strengthening of structural elements similar to fiber reinforced polymer (FRP). Finite element (FE) method based Numerical investigation for evaluation of axial strength of SSWM strengthened plain cement concrete (PCC) and reinforced cement concrete (RCC) columns is presented in this paper. PCC columns of 200 mm diameter with height 400 mm, 800 mm and 1200 mm and RCC columns of diameter 200 mm with height of 1200 mm with different number of SSWM wraps are considered for study. The effect of concrete grade, height of column and number of wraps on axial strength is studied using finite element based software ABAQUS. The results of numerical simulation are compared with experimental study and design guidelines specified by ACI 440.2R-08 and CNR-DT 200/2004. As per numerical analysis, an increase in axial capacity of 15.69% to 153.95% and 52.39% to 109.06% is observed for PCC and RCC columns respectively with different number of SSWM wraps.

• Journal of Aerospace System Engineering
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• v.15 no.6
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• pp.59-65
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• 2021

In this paper, the transmission characteristics of the multi-layered composite material with wire mesh and honeycomb core for aircraft applications have been analyzed with the proposed method. The proposed method converts the conductive wire mesh into effective layer, while for the dielectric honeycomb core, effective permittivity has been derived based on volume fraction with the proposed method. The proposed method has been verified through comparison with full-wave simulation and revealed excellent. In addition, the calculation time of the proposed method is a few order of magnitude faster in comparison with the full-wave simulation.