• Structural Engineering and Mechanics
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• v.85 no.5
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• pp.573-592
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• 2023

This paper presents a careful theoretical investigation into interfacial stresses in composite aluminum-slab reinforced concrete beam bonded by a prestressed hybrid carbon-glass composite material. The model is based on equilibrium and deformations compatibility requirements in and all parts of the strengthened beam, i.e., the aluminum beam, the slab reinforced concrete, the hybrid carbon-glass composite plate and the adhesive layer. The theoretical predictions are compared with other existing solutions. Numerical results from the present analysis are presented both to demonstrate the advantages of the present solution over existing ones and to illustrate the main characteristics of interfacial stress distributions. It is shown that the stresses at the interface are influenced by the material and geometry parameters of the composite beam. This research is helpful for the understanding on mechanical behaviour of the interface and design of the hybrid structures.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.305-308
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• 2008

This paper presents the results of an experimental study carried out Prestressed Concrete Slab System of WAffle Shape(WAS), was perfomed in order to inverstigate it connection shear behavior according to primary paramaters: connection interval, filling matarial. Specimen is produced in Precast Concrete factories and it comprised one WAS panel and two half WAS panels and then it is filled with packing. Within the ranges of the parameters of the connection details used in this test, connections can develop greater shear strength than the nominal shear strength and the design service load for parking structures.

• Structural Engineering and Mechanics
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• v.78 no.3
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• pp.319-332
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• 2021

The wood-concrete composite is an interesting solution in the field of Civil Engineering to create high performance bending elements for bridges, as well as in the building construction for the design of wood concrete floor systems. The authors of this paper has been working for the past few years on the development of the bonding process as applied to wood-concrete composite structures. Contrary to conventional joining connectors, this assembling technique does ensure an almost perfect connection between wood and concrete. This paper presents a careful theoretical investigation into interfacial stresses at the level of the two interfaces in composite wooden beam- reinforced concrete slab strengthened by external bonding of prestressed composite plate under a uniformly distributed load. The model is based on equilibrium and deformations compatibility requirements in all parts of the strengthened composite beam, i.e., the wooden beam, RC slab, the CFRP plate and the adhesive layer. The theoretical predictions are compared with other existing solutions. This research is helpful for the understanding on mechanical behaviour of the interface and design of the CFRP- wooden-concrete hybrid structures.

• Magazine of the Korea Concrete Institute
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• v.9 no.4
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• pp.66-85
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• 1997

• Journal of the Korean Society for Railway
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• v.1 no.1 s.1
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• pp.30-39
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• 1998

The functions of diaphragms at abutments and piers of PSC box girder railway bridge are to transfer forces from the superstructure onto bearings or columns and to stiffen the superstructure cross-section against in -plane deformation. Due to stress disturbance at diaphragm, the design for the diaphragm using conventional design method is relatively irrational than those for other structural members. And, due to contribution to boundary condition of deck slab by the diaphragm, the behavior of deck slab near the diaphragm is different from that of the deck slab obtained from two dimensional analysis of the bridge, which is basis for the design of deck slab. In this paper, three dimensional behavior of deck slab near the diaphragm of prestressed concrete (PSC) box girder railway bridge constructed by the precast span method are analyzed by using three dimensional finite element modeling and using the strut-and-tie model design of the diaphragm are presented. The modeling techniques used in this paper can be applied effectively to examine the causes of cracks at deck slab near diaphragm and to design diaphragm rationally.

• KCI Concrete Journal
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• v.12 no.1
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• pp.17-22
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• 2000

This Paper deals with the analysis of both unstrengthened and strengthened prestressed concrete girder bridges. Finite element method is utilized to perform the analysis of superstructures. Based on the grillage method of analysis. emphasis is Placed on the modeling techniques for structures. The conventional grillage method of analysis is modif'=ed so that the interaction between the slab and gilder behaviors can be taken into account in the analysis A Prototype of simply supported prestressed I-type girder bridge is selected for the analysis. The results of numerical analyses are compared with those of load test. The results of analysis indicate that the proposed method of analysis gives more realistic response of bridges than the conventional grillage method.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.267-270
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• 2005

The section of double-tee is considered as one of the most efficient type for flexure. However, the depth of it is bigger then that of other slab systems. The story height of it is also increased because the duct space is required under the double tee in addition to their net depth. Thus, a new modified double-tees with the nib length of 1.58m was suggested in this study. The story height of this one is reduced up to 450mm by including duct space under the nib at the ends of slab. The four ends of the modified two single tees were designed by strut-tie models. Shear tests were performed on them to verify the safety. The ultimate shear strengths of non-prestressed two specimens were larger than the design shear strength by strut-tie models. They were failed in ductile with many distributed flexural crackings. However, the other prestressed two specimens showed much stiffer behaviors, less deflection. and strength than those of prestressed.

• Steel and Composite Structures
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• v.36 no.1
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• pp.103-118
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• 2020

The static behavior of grouped large-headed studs (d = 30 mm) embedded in ultra-high performance concrete (UHPC) was investigated by conducting push-out tests and numerical analysis. In the push-out test, no splitting cracks were found in the UHPC slab, and the shank failure control the shear capacity, indicating the large-headed stud matches well with the mechanical properties of UHPC. Besides, it is found that the shear resistance of the stud embedded in UHPC is 11.4% higher than that embedded in normal strength concrete, indicating that the shear resistance was improved. Regarding the numerical analysis, the parametric study was conducted to investigate the influence of the concrete strength, aspect ratio of stud, stud diameter, and the spacing of stud in the direction of shear force on the shear performance of the large-headed stud. It is found that the stud diameter and stud spacing have an obvious influence on the shear resistance. Based on the test and numerical analysis results, a formula was established to predict the load-slip relationship. The comparison indicates that the predicted results agree well with the test results. To accurately predict the shear resistance of the stud embedded in UHPC, a design equation for shear strength is proposed. The ratio of the calculation results to the test results is 0.99.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.399-404
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• 1999

An improved finite element modeling technique is proposed for the assessment of load carrying capacity partilly prestressed concrete beam bridges. Based on the finite element method of analysis, shell and frame elements are utilized to model the slab and beams of the superstructure, respectively. In the modeling of superstructure, the emphasis is placed on the use of rigid link between the middle surface of slab and mid-plane of beam. This paper also includes the comparision of three different equations that used in the calculation of effective moment of inertia for the partially prestressed concrete beams. Numerical analysis is performed for the unstrengthened and strengthened bridges. The obtained results are compared with those of load test for a prototype bridge. Agreement with the numerical solutions by using the proposed method and load test results is generally excellent.

• Computers and Concrete
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• v.1 no.3
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• pp.355-369
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• 2004

This paper presents a study of four finite element techniques that can be used to model slabon-beam highway bridges. The feasibility and correctness of each modeling technique are examined by applying them to a prestressed concrete I-beam bridge and a prestressed concrete box-beam bridge. Other issues related to bridge modeling such as torsional constant, support conditions, and quality control check are studied in detail and discussed in the paper. It is found that, under truck loading, the bending stress distribution in a beam section depends on the modeling technique being utilized. It is observed that the behavior of the bridge superstructure can be better represented when accounting for composite behavior between the supporting beams and slab.