• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.1
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• pp.29-37
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• 2020

This study is to investigate the effect of a retrofitted reinforced concrete frame with non-seismic details strengthened by embedded steel moment frames with an indirect joint, which mitigates the problems of the direct joint method. First, full-scale experiments were conducted to confirm the structural behavior of a 2-story reinforced concrete frame with non-seismic details and strengthened by a steel moment frame with an indirect joint. The reinforced concrete frame with non-seismic details showed a maximum strength of 185 kN at an overall drift ratio of 1.75%. The flexural-shear failure of columns was governed, and shear cracks were concentrated at the beam-column joints. The reinforced concrete frame strengthened by the embedded steel moment frames achieved a maximum strength of 701 kN at an overall drift ratio of 1.5% so that the maximum strength was about 3.8 times that of the specimen with non-seismic details. The failure pattern of the retrofitted specimen was the loss of bond strength between the concrete and the rebars of the columns caused by a prying action of the bottom indirect joint because of lateral force. Furthermore, methods are proposed for calculation of the specified strength of the reinforced concrete frame with non-seismic details and strengthened by the steel moment frame with the indirect joint.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.325-328
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• 2006

Joint structures of composite truss bridges can have the same details for the connection between diagonal members and upper concrete slab as the connection between diagonal members and lower concrete slab. Adequate connection details should be decided according to design codes, constructibility, and economical evaluation. It is necessary to clarify the design check items and load transferring mechanism because combined external loads on composite truss bridges are concentrated at the joints. Joints with gusset plates and stud connectors are applied and complicated joint details may arise some problems in construction. This paper deals with experimental evaluation of the joints in composite truss bridges and proper design provisions were investigated to enhance the details. Push-out test specimens with group studs were fabricated and the effects of grouping and bent studs were studied.

• Journal of Korean Association for Spatial Structures
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• v.21 no.4
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• pp.81-89
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• 2021

Recently, interest in OSC(Off Site Construction) is increasing due to the trend of a decrease in skilled workers and an increase in labor costs. In this regard, PC(Precast Concrete) is being reviewed for apartments, the most common type of housing in Korea. As the biggest concern for PC apartment houses, civil complaints such as inter-floor noise and leakage were presented. In this study, the details of the joints were reviewed based on the past cases of PC apartments, and the details of the recently constructed or planned PC apartments were investigated. Through this, the leakage path in the past was analyzed through the existing research literature and data. And wall type RC and PC apartment joint leakage test was performed and we found the needs for a detail of waterproof steps, sealant. Also, joint details were investigated for a rahmen type apartment housing under construction. At last, A discussion was conducted on the direction for a detailed proposal of an improved joint in the future.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.8
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• pp.15-22
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• 2019

According to Kenneth Frampton, the modern architecture starts to be recognized as the poetics of construction and lays a great weight in its value on the technology of making forms and the inherent meaning in the tectonics. The tectonic connotes not only the technological construction of the architecture but also ontological details as the joint of material and texture. The works of Carlo Scarpa are examples to prove the way how the ontological meanings are exposed in the tectonic form of architecture. The purpose of this study was to analyze the connections between Carlo Scarpa's architectural thoughts and visual logic(schemata) from the characteristic of details in his work during the 1950s to 1970s. Through the analysis, the Italian tradition in the architecture is reinterpreted through isolation and break of recollected montages. Carlo Scarpa makes spatial fragments and aspects of reinterpreting in surroundings and situation with the architectural place in Venezia. As a result, the unique details of his craftsmanship provide lessons on how to reinterpret the traditional architecture. In conclusion, Carlo Scarpa's architecture emphasizes the passage of its perceptive experience aspects as a dis-joint of tectonic forms. It may imply the significance of his philosophical approach, especially to the ontological architecture and tectonics.

• Steel and Composite Structures
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• v.19 no.1
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• pp.209-221
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• 2015

Results from an experimental study on the seismic response of six composite reinforced concrete column-to-steel beam interior joints are presented. The primary variable investigated is the details in the joint. For the basic specimen, the main subassemblies of the beam and column are both continuous, and the steel beam flanges extended to the joint are partly cut off. Transverse beam, steel band plates, cove plates, X shape reinforcement bars and end plates are used in the other five specimens, respectively. After the joint steel panel yielded, two failure modes were observed during the test: local failure in Specimens 1, 2 and 4, shear failure in Specimens 3, 5 and 6. Specimens 6, 3, 5 and 4 have a better strength and deformation capacity than the other two specimens for the effectiveness of their subassemblies. For Specimens 2 and 4, though the performance of strength degradation and stiffness degradation are not as good as the other four specimens, they all have excellent energy dissipation capacity comparing to the RC joint, or the Steel Reinforced Concrete (SRC) joint. Based on the test result, some suggestions are presented for the design of composite RCS joint.

• Earthquakes and Structures
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• v.25 no.4
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• pp.283-296
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• 2023

This paper presents experimental and numerical studies of seismic performance on reinforced concrete (RC) wide beam (WB) joints. Two RC-WB joint specimens and one conventional RC joint specimen were fabricated using the reinforcing details of longitudinal reinforcing bars in a beam as a variable, and quasi-static cyclic loading tests were performed. The results were used to compare and analyze the load-drift ratio relationship, failure mode, and seismic performance of the specimens quantitatively. In addition, a finite element (FE) analysis of the RC-WB joint was conducted, and the rationality of the FE model was validated by comparing it with the test results. Based on the FE model, a parametric study was conducted, where the ratio of longitudinal reinforcing bars placed on the outer and inner parts of the joint (𝜌_ex/𝜌_in) was a key variable. The results showed that, in the RC-WB joint, an increase of 𝜌_ex/𝜌_in leads to more severe damage to concrete, which reduces the seismic performance of the RC-WB joints.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.19-29
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• 2015

As the half-depth precast concrete decks are increasingly applied to the construction sites, researches on connection details have been increased. For design of concrete bridge deck with half-depth precast panels, it is required to provide appropriate details of transverse loop joints between panels. In this paper, the structural performance of precast decks was evaluated to investigate continuity of the proposed loop joint details. From the results, the validity of the joints for the continuity of deck was observed in the aspect of flexural strength and crack control. The ultimate strength increased 1.52 times as the reinforcement spacing in the joint was reduced. In terms of crack control, direct crack width calculation for the loop joint showed appropriate results comparing with measured crack width.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.131-132
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• 2020

Recently, interest in OSC(Off Site Construction) is increasing due to the trend of a decrease in skilled workers and an increase in labor costs. In this regard, PC(Precast Concrete) is being reviewed for apartments, the most common type of housing in Korea. As the biggest concern for PC apartment houses, civil complaints such as inter-floor noise and leakage were presented. In this study, the details of the joints were reviewed based on the past cases of PC apartments, and the details of the recently constructed or planned PC apartments were investigated. Through this, the leakage path in the past was analyzed through the existing research literature and data, and a discussion was conducted on the direction for a detailed proposal of an improved joint in the future.

• International Journal of Korean Welding Society
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• v.1 no.1
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• pp.51-57
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• 2001

Effect of the joint details on the stress distribution over a slot structure has been studied in order to improve its fatigue life using a finite element analysis. The joint details of interest are the radius and height of scallop at the stiffener as well as the mis-alignment between the stiffener and longitudinal member. For a slot structure currently used, the stiffener heel is subjected to the maximum stress for a given external load, where is a potential fatigue crack initiation site. The stresses at the stiffener heel and toe decrease both by increasing the scallop radius and more significantly by increasing the mis-alignment while no notable effect of the scallop height on it is appreciated. A proper combination of these factors makes it possible to reduce the stresses at the stiffener heel and In, theoretically, more than 50%. This is attributed to the modification of the stress distribution over the slot structure including the transition of the maximum stressed region from the stiffener heel to the slot surface of the transverse web. Such then results in a g[eat improvement of the fatigue life of the slot structure.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.133-140
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• 2003

The objective of this study is to clarify the seismic capacity and the characteristics in the hysteretic behavior of RC structures with non-seismic detailing. Interior and exterior beam-column subassemblages were selected from a ten-story RC building and six 1/3-scale specimens were constructed with three variables; (1) with and without slab, (2) with and without hoop bars in the Joint region, (3) upward and downward direction of anchorage for the bottom bar in beams of exterior beam-column subassemblage. The test results have shown; (1) in case of interior beam-column subassemblage, there is no almost difference between nonseismic and seismic details in the strength and ductility capacity; (2) the Korean practice of anchorage (downward and 25 $d_{b}$ anchorage length) in the exterior Joint caused the 10％~20％ reduction of strength and 27％ reduction of ductility iii comparison with tile case of seismic details; and the existence of hoop bars in the joint region shows no effect in shear strain.n.