• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.6
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• pp.169-180
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• 2007

Among several splicing system of reinforcing bar, the grout-filled splice sleeve system has been applied widely. However, as the splice sleeve for high strength rebar as SD500 is not yet made in korea, the development of splice sleeve for high strength reinforcing bar are required as soon as possible. It is the purpose of this study to develop the steel pipe sleeve for high strength rebar as SD500 and estimate its structural performance by monotonic loading test. The experimental variables adopted in this study are the development length of rebars, types of sleeve etc. The results of this study showed that the developed steel pipe splice sleeve system for high strength reinforcing bar as SD500 retained the structural performance required in domestic, ACI and AIJ criteria. And it is considered that the study result presented in this paper can be helpful in developing reasonable design method of steel pipe splice sleeve system for high strength reinforcing bar as SD500.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.1
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• pp.27-34
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• 2012

The objective of this study is to evaluate the stiffness of mortar-filled sleeve bar splice using estimation method of failure mode in the sleeve reinforcement splice. To attain this goal, we analyzed the test results of 261 actual-sized mortar-filled sleeve splice specimens. The study results showed that the estimation method of the failure mode in mortar-filled sleeve bar splice made an effective estimate of the stiffness in this bar splice with the exception of specimens with SD500 bars and smooth pipe sleeve. Especially, of the specimens with cast sleeve or uneven pipe sleeve in the range of reinforcement fracture using the estimation method of the failure mode in mortar-filled sleeve splice, specimens over 98% with SD400 bars and all specimens with SD500 bars had the stiffness capacity of higher than "A" class of AIJ code in monotonic loading. In addition, of the specimens in the range of reinforcement fracture using the estimation method of the failure mode in mortar-filled sleeve splice, all specimens with SD400 bars and SD500 bars had the stiffness capacity of higher than "A" class of AIJ code in cyclic loading.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.345-349
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• 2019

In Korea, the mountainous area occupies more than 70% of the whole country, cutting of earth slope that cuts a part of the ground surface is widely used when building infrastructures such as road, railroad, and industrial complex construction. In recent years, regulations on environmental damage have become more strict, and various methods have been developed and applied. Among them, Concrete-Panel Retaining Wall technique is actively applied. Concrete-Panel Retaining Wall is a method to resist horizontal earth pressure by forming a wall by attaching a precast retaining wall to the front of the support material and increasing the shear strength of the disk through reinforcement of the support material. Soil nailing, earth bolt, and ground anchor are used as support material. Among them, ground anchor is a more aggressive reinforcement type that introduces tensile load in advance to the steel wire, and a large concentrated load acts on the front panel. This concentrated load is a factor that creates cracks in the concrete panel and reduces the durability of the retaining wall itself. In this study, steel pipe sleeves and reinforcements were purchased at the anchorage of the panel to prevent cracks, and by applying bumpy shear keys to the end of the panel, the weakness of the individual behavior of the existing grout anchors was improved. The problem of degraded landscape by exposure to front concrete of retaining wall and protrusion of anchorage was solved by the production of natural stone patterns and the construction of sections that do not protrude the anchorage. In order to verify the effectiveness of anti-crack sleeves and reinforcements used in the null, indoor testing and three-dimensional numerical analysis have been performed, and the use of steel pipe sleeves and reinforcements has demonstrated the overall strength increase and crack suppression effect of panels.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.1
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• pp.85-93
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• 2013

In order to make a more reasonable evaluation on the stiffness of the high-strength mortar-filled sleeve bar splices under cyclic loading, we investigated and analyzed the existing experiment data of 106 full-sized reinforcing bar splices with test variables such as compressive strength of mortar, development length of reinforcement and sleeve type, etc. The following were found: 1) If mortar and the reinforcement development length with $f_{g^*}$(L/d) of more than 340 is used, the cast iron sleeve bar splices for SD350 and SD400 will have the stiffness of higher than A class of the AIJ code. 2) If mortar and the reinforcement development length with $f_{g^*}$(L/d) of more than 400 is used, the cast iron sleeve splices and pipe sleeve splices for SD500 will have the stiffness of higher than A class of the AIJ code.

• Journal of Korean Society of Steel Construction
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• v.17 no.4 s.77
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• pp.419-429
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• 2005

The objective of this study is to clarify the structural features of members consisting of a connection, as part of the previous study on the CFT column-to-beam tensile connection with a combined cross diaphragm. This connection has the following merits: it evenly distributes the stress on the beam flange and the diaphragm and reduces the stress concentration by improving the stress transfer route and restraining the abrupt deformation of the diaphragm. Finite element analysis was performed to find out the stress transfer through the sleeve, which is an important member of the connection with a combined cross diaphragm. The length and thickness of the sleeve were used as variables for the analysis. The analysis results showed that the length and thickness of the sleeve did not influence the capacity of the connection and played the role of a medium for the transfer of the stress from the diaphragm to the filled concrete. It was proposed that the appropriate length of the sleeve have the same value as the diameter of the sleeve and that the appropriate ratio of the sleeve diameter to the sleeve thickness be 20. Two equations for the evaluation of the load carrying the capacity of the connection were also proposed through the modification of the evaluation equation suggested in the previous study.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.519-526
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• 1997

The purpose of this study is to develop the analytical model for the reinforcement bar connection in group-filled steel pipe sleeve, which consists of beam elements for the reinforcement bar and shell elements for the sleeve and the mortar and spring elements for the bond stress-slip relationship. In the reinforcement bar connection using grout-filled steel pipe sleeve, the major variables are the bond stiffness between reinforcement bar and mortar($K_1$) and between sleeve and mortar($K_2$). It is nearly difficult to predict the exact bond stiffness with the experimental results. Therefore, The linearly elastic analyses using ABAQUS, FEM package show the validity of the mathematical equations for the bond stiffness and the choice of material elements in this paper. To predict the behaviour between yield and ultimate tensile strength, the nonlinear analyses must be performed henceforth.