Papers by Keyword: Bending Moment

Abstract: The main purpose of this study is a numerical assessment of the consequences of an explosion of a hydrogen-air cloud on the personnel of a hydrogen fueling station and the strength of a protective solid wall of certain dimensions. An explosive gas mixture is formed as a result of the destruction of high-pressure cylinders, the number of which determines the size of the cloud, the power of the explosion, and the scale of the consequences of environmental impact. To obtain the spatio-temporal distribution of the maximum overpressure and the impulse of the shock wave compression phase, a mathematical model of the dispersion of an active gaseous admixture is used, taking into account the chemical interaction with air oxygen. The probable consequences of the shock-impulse impact on the personnel at the control point are carried out using probit analysis. The values of the maximum bending moment and stress at the base of the protective wall, which result from the impact of the blast wave, are used to deterministically estimate the minimum wall thickness necessary for the safe operation of the protective device. The mathematical model takes into account the complex terrain and the three-dimensional non-stationary nature of the shock wave propagation process, and it is a source of data necessary to solve the problem of the strength of solid objects located in the area of baric perturbation of the gaseous medium. The developed methodology makes it possible to carry out a comparative analysis of the effectiveness of protective structures in relation to the power of the explosion.

Abstract: At the production of the steel thick-walled large-diameter pipes according to UOE-technology at the tube electrical welding aggregation 1020 (TEWA 1020), the steel sheet is in series bent on the flanging press, the pre-forming press and the final-forming press. When the steel sheet is deformed on the final-forming press, the excessively curved sections of the sheet are partially unbent in the opposite direction. The calculation of sheet’s curvature at the alternating bending causes the significant difficulties because of Bauschinger’s effect at bending, in which the mechanical characteristics of the steel change significantly. In this paper, the analytical method for calculating the final curvature of steel pipe billet at the alternating bend at UOE-technology is proposed. The results of the paper can be applied in metallurgy.

Abstract: Concrete segments are widely used to support soil and water loadings in shield-excavated tunnels. Concrete segments burden simultaneously to the loadings of bending moments and axial forces. Based on plane deformation assumption of material mechanics, in which plane section before bending remains plane after bending, ultimate bending moment model is proposed to compute ultimate bearing capacity of concrete segments. Ultimate bending moments of concrete segments computed by analytical models agree well with numerical simulation results by FEM. The accuracy of proposed analytical computational model for ultimate bending moment of concrete segments is numerically verified. The analytical computational model and numerical simulation for a practical engineering case indicate that the ultimate bending moment of concrete segments increases with increase of axial force on concrete segment in the case of large eccentricity compressive state.

Abstract: The main task of construction is providing buildings with the property to remain operable throughout the entire life cycle. The level of bearing capacity, both of individual structures and buildings as a whole, depends on many factors.

Abstract: Experience gained in design, erection and operation of span reinforced concrete structures has proved that practically all of them are subject to complex stress-strain state. At that, the researchers pay considerable greater attention to calculation of strength, deformation analysis and determination of crack resistance in normal cross-sections than to calculation of their support zones, including oblique sections, which results are generally taken into account for determining the section dimensions and the quantity of the cross reinforcement.

Abstract: Wave load prediction of ship should be considered in the design stage of ship’s construction. The excessive of wave load might cause a structural failure of ship during operational in seaway. The bending moment might be experienced on the ship structure that it contributes to stress concentration on the particular part of construction. This paper describes the prediction of bending moment and shear forces of the warship corvette type considered to the sea condition of Indonesia. The 3D diffraction theory was adopted to analyze ship’s motion responses, bending moments, and shear forces numerically. In this numerical simulation, the variations of speed and heading angle of ship were performed with respect to environmental condition of sea state 4, 5, 6 and 7. The simulation results had shown that the maximum shear force and bending moment was occurred on the area of mid-ship.

Abstract: The paper contains a discussion on the impact of specimen shape and load type on fatigue life of aluminium alloy 2024. Completed fatigue tests involved bending of round and square cross-section specimens. Tests with controlled amplitude of bending moment and controlled amplitude of energy parameter were performed for each specimen type. The tests at controlled amplitude of energy parameter were carried out for an energy model proposed by Macha and partners [1].

Abstract: There is a general condition of the stress created by superficial forces in praxis. It can be also simplified when the shifting the forces and bending torques are equal to zero, or we can ignore them because they are too low. In term of draft it is just a condition which has the best result when the material for the construction is exploited. The edge of the cylindrical container failures are the differential base for the axisymmetric shell within an internal pressure. That main point of that contribution is the effect of the internal load and the bending effects to joining pressure of the slice cylindrical part and the plate bottom.

Abstract: The article deals with more precise method of bending moment determination for rigid plastic work hardening material. Unlike earlier methods, a new methodology takes into account the real shape of the deformed tube cross-section after bending. The real centroid position of the tube cross-section, the change of wall thickness and the irregularly deformed tube cross-section are considered. The paper presents a possible way of determining the real bending moment, reflecting the geometrical changes of the “flattened” cross-section. This approach is based on the subsequent integration of elementary bending moments, which reflects successive changes of the bending stress and a material model as well.

Abstract: Mechanical analysis of flexible pipe during installation is presented in this paper. The configuration, tension and bending moment of the flexible are important issues during the installation. A reasonable theoretical model is proposed to handle the pipe configuration and the loads during installation. Numerical iteration program for the model is developed to get the tension, bending moment distribution and the pipe configuration. Two segments which are suspended segment and seabed segment are analyzed with different calculation model for their different load conditions and boundary conditions. Finite element model is established by Abaqus to verify the results from the theoretical model. The results from theoretical are very close to the ones got from FEM. Typical installation method J-lay method is applied to perform the FEM and numerical analysis.