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In this study, it was investigated that the bearing behaviour of reinforced concrete beams and steel elements in the positive moment zone. The bearing behaviour and the bearing capacities of the reinforced concrete beams with steel elements agglutinated by the epoxy resin. Moreover, certain model researches are done theoretically to determine the distribution of the sliding and the normal strain throughout the coherence surface of the beams which are composed of the reinforced concrete plate and the steel elements agglutinated with the epoxy resin and equation are suggested for these kind of composite due to the results. Test results indicated that the bonding strength between steel and steel is 470% longer than that of concrete to steel.

The composite beams which are composed of reinforced concrete floor plate and steel beams or bridge floor and steel beams are more economical than the steel beams that carries reinforced concrete plate freely on its own. Because, in a composite beam the tensile component of the force pair which is due to bending is carried by the steel profile and the compressive component that is also due to bending is carried by either reinforced plate or a of the reinforced concrete plate and steel profile cooperation system. So, the steel profiles get rid of carrying the compressive component of bending either completely or partially. In this way, the reinforced concrete plate carrying the dead load turns out to be a useful element which carries the compressive component and in this cooperation, the lever arm of the force pair become greater, so a good economical factor is constituted by this situation [1], [2], [3], [4], [5] and [6]. The composite beams are always lighter than the reinforced concrete beams. In the composite beam, less steel is used than the reinforced concrete beams which have the same height. In the composite beams, a combination material called epoxy resin is used to provide the cooperation between the prefabricated reinforced concrete plate and the steel profile. During the cooperation between the concrete and the steel profile, the sliding and the lifting forced between the two materials are reacted by the help of the epoxy resin. There are not more researches about this subject (especially, about the composite beams which are consist of the reinforced concrete plate and the steel profile combined by the epoxy resin in the positive moment zone). Generally in the studies with the epoxy resin, the cooperation of the steel plate and the reinforced concrete beam is researched. The main purpose of our study is researching the bearing behaviour of reinforced concrete beams and steel elements in the positive moment zone, and also researching how the cooperation by means of the steel profile and plates existing in the reinforced concrete beam (agglutinated with epoxy resin) is materialized (sliding and separation of epoxy resin from the steel, etc.) About this subject, in the experimental studies which are carried out by Swamy and Jones [7], [8] and [9], the bearing capacities and the bearing behaviour of the reinforced concrete beams with steel elements agglutinated by the epoxy resin and how the sliding and the separation between the steel element and the reinforced concrete beam is materialized, are researched. Besides, in the studies of Roberts and Haji-Kazemi (Roberts 1989) [10], [11] and [12], certain model researches are done theoretically to determine the distribution of the sliding and the normal strain throughout the coherence surface of the beams which are composed of the reinforced concrete plate and the steel elements agglutinated with the epoxy resin and equation are suggested for these kind of composite due to the results. The objective of the study is to research the influence of the epoxy resin which provides the cooperation of the prefabricated reinforced concrete plate and the steel profile in the positive moment zone on the bearing behaviour of the composite beam and also to find out how the additional equipment located in the prefabricated reinforced concrete plate and the steel profiles agglutinated with the epoxy resin affect the bearing behaviour of the composite beam. Besides in this study, as a result of the deformation of the composite beam under loading, the epoxy resin’s degree of precaution on the rising and sliding of the prefabricated reinforced concrete collaborating with the steel profile is researched. The quality of the reinforcement that is replaced in the reinforced concrete plate is BS-1 and that of the steel profile which forms the composite beams is St 37. As the results of the tensile tests, the quality of the steels which are used is determined exactly. The results of this experimental study will be compared with that of the theoretical computations. In the subject which is about the cooperation of the prefabricated reinforced concrete plate and the steel profile, how the variation of interconnection element distances affect is researched and certain suggestions are done.

In the first stage of this work the adhesive between composite concrete beam and the steel profile (INP 120) were applied at six points. The deflection and loading capacity of this system were obtained. In the second stage the numbers of adhesion points were risen to eight constraint points. All the test results of the first and second stages are shown in Table 1. The experimental results are summarized in: • The adhesion bonding is between the steel plate of the composite concrete and the steel profile and all loads are carried out by the epoxy resin. In examining the strength of the adhesive bond, our preliminary studies showed that in case of adhesion between the concrete and steel profile, the tensile strength of the concrete was nearly zero. This resulted in shearing of the profile from the concrete which resulted to weak joints and failure. Therefore the reach a sound construction the adhesion should be between the steel plates of the composite concrete and steel profile. The bonding strength of the epoxy for steel to steel case in much higher that of concrete to steel. • The results of the first and second stages tests showed that: for 6 fixing points construction system the average loading capacity is 5.63 kN and the bonding area is about 696 cm2. For 8 fixing points system the average loading capacity is 7.86 kN and bonding area is 928 cm2. It is well crown fact that the longer the adhesion area the stronger is the bonded joint. Therefore using 8 fixing points the sounder is the construction. The longer the number the shorter are the distance between the joints with minimize the deflection. Examining the influence of the distance between the constraint points is planned as a further work is this field. • The bonding strength between steel and steel is 470% longer than that of concrete to steel. The most economical and sound composite prefabricated to profile steel joints are obtained by using adhesive epoxy between steel plates of the composite and the steel beam.