Osgood Model Research Articles

An orthogonal component method for steel girder-concrete abutment connections in integral abutment bridges

To predict the moment – rotation relationships of steel girder-concrete abutment connections with perfobond connectors, this paper develops an orthogonal component method, which is modified from the conventional component method. The connections were first disassembled into several horizontal and vertical components, and these components were simplified into translational springs. Next, the equations for the mechanical properties of each spring were determined with analytical analyses, and were calibrated against a number of numerical models. The springs were then reassembled and further simplified into two parallel rotational springs to calculate the rotational stiffness, the yield moment and the yield rotation of the girder-abutment connections. Finally, based on the Ramberg and Osgood model, the moment-rotation curves of the connections were determined, and were compared with numerical and experimental results. The results show that the proposed method is feasible to predict the rotational behavior of the girder-abutment connections, and can achieve fair accuracy in most cases when the shear deformation of concrete abutment is considered. The proposed method can also predict the shear force distribution among perfobond connectors. The main feature of the proposed method is that it can incorporate the contribution of perfobond connectors and vertical forces in the connections.

Experimental and Numerical simulation of a Three Point Bending Test of a Stainless Steel Beam

An advanced simulation process of a stainless steel member in ANSYS technology is described in this paper. A three-point bending test of a hot rolled stainless steel material grade 1.4301 (AISI 304) member has been conducted. The cross-section of the beam was IPE80, with the span of the supports equal to 240 mm. The results of the experimental test were compared with the materially and geometrically nonlinear numerical analysis. In order to describe the behavior of the stainless steel material, the Ramberg and Osgood model has been adopted along with multi linear stress-strain description with isotropic hardening feature. The finite element model has been created using software ANSYS classic APDL environment, and the results were compared.

Fracture Assessment of Axial Crack in Steel Pipe under Internal Pressure

Fracture assessment of axial crack in steel pipe subjected to internal pressure is reviewed. Assessment results were obtained using different methods FC, GS and FAD in order to compare between their results and facilitate their use in any maintenance program. Material type and crack geometry are considered as the main two parameters controlling the failure of the pipe. The constitutive equation of the material is represented by the Ramberg – Osgood model. Six different half crack lengths (40, 60, 80, 100, 120,and 140mm) and four values of the ratio between the crack depth and the pipe thickness are considered (0.2, 0.4, 0.6 and 0.8). The relationship between the fracture parameters (i.e., stress intensity factor K and the J-integral) and the crack length for each assessment method is used. The material properties, plane strain fracture toughness KIc as well as the critical value of J-integral Jcr, are used to determine the critical crack size under specified internal pressure. The assessment method that gives smaller critical crack size is the one which is more conservative than the others. The results obtained by using GS and FAD assessment methods show this type of conservation.

Equivoque du concept de linguistique dans les études psycholinguistiques et sociolinguistiques des situations plurilingues [Ambiguous character of the concept of linguistics in the psycholinguistic and sociological studies of the multilingual situations

Equivoque du concept de linguistique dans les études psycholinguistiques et sociolinguistiques des situations plurilingues [Ambiguous character of the concept of linguistics in the psycholinguistic and sociological studies of the multilingual situations