## 1 Introduction  
The hybrid joint was developed from the technique of using adhesive and bolts to bond different materials, which are applied to join steel deck and fiber-reinforced plastic (FRP) panels. The different proposals of many researchers are summarized as follows: [PERSON] and [PERSON] [1] developed a proposal for a hybrid union of a military ship, between a steel deck and composite superstructure with symmetrical connection is made using an adhesive double joint. This joint was proven by converting two German frigates into yachts. [PERSON] and [PERSON] [2] developed the symmetrical joint, an adhesive double type with a sandwich panel and without a bevel in connection. The joint was fixed using adhesive and supported by a mechanical fastening. [PERSON] and [PERSON] [3, 4] developed an asymmetric single-type adhesive joint with a sandwich panel and transition level; the critical load of the joint was absorbed by the bolts. [PERSON] and [PERSON] [5] proposed a hybrid joint with bolts, adhesive, and a steel plate that could be welded directly to the deck and screwed or joined to a sandwich-type laminate. [PERSON], [PERSON], and [PERSON] [6] analyzed the finite elements of a sandwich-type joint, but with a modification, including the inner end of a folded steel plate. [PERSON] [7] proposed a hybrid joint between steel panels and FRP panels; this union has been called 'Comeld-2'. This study focused on the application of composite panels in military and submarine ships. [PERSON] and [PERSON] [8] proposed a US Navy ONR's Navy Joining Center (NJC) adhesive joint consisting of a metal \(H\) profile to generate an adhesive double joint, which is to be welded to the deck. The lamination used was vinyl ester resin and a balsa core. [PERSON], [PERSON], [PERSON], and [PERSON] [9] performed a local fatigue analysis on a composite-steel panel, between the joint of the deck and the side of a frigate superstructure. [PERSON] and [PERSON] [10] conducted experimental tests of hybrid joints between steel and fiber-reinforced panels, using the infusion method, for different roughness states of the steel. [PERSON] and [PERSON] [11], in their publication, analyzed the effect of the main parameters of the hybrid joint, sandwich-type with adhesive, through applying tension loads. [PERSON] [12] and [PERSON] [13] studied the type of construction used by the Kockums shipyard for the joints of reinforced fiberglass/carbon fiber reinforced polymer (CFRP) superstructures with steel hulls. The panel contact was made on the U profile through adhesives. The mentioned hybrid joints were applied mainly to join FRP superstructures, masts, and accessories to a metal structure. The proposed joints were mostly of the adhesive type, and a few involved fixing bolts. The methods proposed had some limitations as follows: the difference between the thermal expansion coefficients; the corrosive effect if the steel structure was used; the difficulty of fixing the FRP panel girders to the metal structure; and the fixing of the interface structure to the metal panel. In the present investigation, we used a tubular hybrid joint, as proposed in [14; 15], as an option that allowed the following: prefabricating the FRP block, minimizing the difference in the thermal expansion coefficients, and minimizing the corrosive effect due to the metal surfaces that are protected with an adequate epoxy anticorrosive treatment. Researchers proposed different techniques for the analytical study of adhesive single-lap joints; these methods can be classified as explicit and implicit. Explicit methods to estimate shear and normal stresses (closed form) are as follows: [PERSON] [16] was the first to study single adhesive joints, he only proposes the shear stress formula because it does not consider deformations in the adherents. [PERSON] and [PERSON] [17] propose formulas considering the deformation in the adherents due to the bending moment generated by the eccentricity of the applied force, its method only applies to balanced joints and thin adherents.