Time-dependent internal forces in uncracked structures: analysis by the displacement method

2018 ◽  
pp. 170-199
Keyword(s):  
Time Dependent ◽  
Displacement Method ◽  
Internal Forces

Study of the Influence of the Beam-Column Line Stiffness Ratio on the Frame Structure Load Capacity Based on MATLAB

2011 ◽  
Vol 71-78 ◽  
pp. 4194-4198
Author(s):  
Shao Qin Zhang ◽  
Hua Hu Cheng
Keyword(s):  
Engineering Design ◽  
Carrying Capacity ◽  
Calculated Result ◽  
Load Capacity ◽  
Frame Structure ◽  
Stiffness Ratio ◽  
Displacement Method ◽  
Structure Form ◽  
The Matrix ◽  
Internal Forces

Statically indeterminate frame, composed of beams and columns, is a widely used structure form in civil engineering. The frame carrying capacity under various actions is related to the absolute stiffness of frame components and relative beam-column line stiffness ratio. The matrix displacement method and programming based on MATLAB were employed in this study to calculate the internal forces and displacements of a 2-bay 2-story frame structure under the action of horizontal loads. The influence of the beam-column line stiffness ratio on the frame load capacity was discussed based on the calculated result. Furthermore some advises were provided about the reasonable beam-column line stiffness ratio for engineering design.

scholarly journals Stress-strain state of shell of revolution analysis by using various formulations of three-dimensional finite elements

2020 ◽  
Vol 16 (5) ◽  
pp. 361-379
Author(s):  
Natalia A. Gureeva ◽  
Yuriy V. Klochkov ◽  
Anatoly P. Nikolaev ◽  
Vladislav N. Yushkin
Keyword(s):  
Finite Element ◽  
Strain State ◽  
Hermite Polynomials ◽  
Mixed Formulation ◽  
Shell Of Revolution ◽  
Shells Of Revolution ◽  
Displacement Method ◽  
Stress Strain ◽  
Stress Strain State ◽  
Internal Forces

The aim of the work is to perform a comparative analysis of the results of analyzing arbitrarily loaded shells of revolution using finite element method in various formulations, namely, in the formulation of the displacement method and in the mixed formulation. Methods. To obtain the stiffness matrix of a finite element a functional based on the equality of the actual work of external and internal forces was applied. To obtain the deformation matrix in the mixed formulation the functional obtained from the previous one by replacing the actual work of internal forces in it with the difference of the total and additional work was used. Results. In the formulation of the displacement method for an eight-node hexahedral solid finite element, displacements and their first derivatives are taken as the nodal unknowns. Approximation of the displacements of the inner point of the finite element was carried out through the nodal unknowns on the basis of the Hermite polynomials of the third degree. For a finite element in the mixed formulation, displacements and stresses were taken as nodal unknowns. Approximation of the target finite element values through their nodal values in the mixed formulation was carried out on the basis of trilinear functions. It is shown on a test example that a finite element in the mixed formulation improves the accuracy of the strength parameters of the shell of revolution stress-strain state.

scholarly journals Comparative analysis of finite element formulations at plane loading of an elastic body

2020 ◽  
Vol 16 (2) ◽  
pp. 139-145
Author(s):  
Natalia A. Gureeva ◽  
Anatoly P. Nikolaev ◽  
Vladislav N. Yushkin
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Elastic Body ◽  
Stiffness Matrix ◽  
Strain State ◽  
Mixed Formulation ◽  
The Finite Element Method ◽  
Displacement Method ◽  
Internal Forces ◽  
The Difference

The aim of the work - comparison of the results of determining the parameters of the stress-strain state of plane-loaded elastic bodies based on the finite element method in the formulation of the displacement method and in the mixed formulation. Methods. Algorithms of the finite element method in various formulations have been developed and applied. Results. In the Cartesian coordinate system, to determine the stress-strain state of an elastic body under plane loading, a finite element of a quadrangular shape is used in two formulations: in the formulation of the method of displacements with nodal unknowns in the form of displacements and their derivatives, and in a mixed formulation with nodal unknowns in the form of displacements and stresses. The approximation of displacements through the nodal unknowns when obtaining the stiffness matrix of the finite element was carried out using the form function, whose elements were adopted Hermite polynomials of the third degree. Upon receipt of the deformation matrix, the displacements and stresses of the internal points of the finite element were approximated through nodal unknowns using bilinear functions. The stiffness matrix of the quadrangular finite element in the formulation of the displacement method is obtained on the basis of a functional based on the difference between the actual workings of external and internal forces under loading of a solid. The matrix of deformation of the finite element was formed on the basis of a mixed functional obtained from the proposed functional by repla-cing the actual work of internal forces with the difference between the total and additional work of internal forces when loading the body. The calculation example shows a significant advantage of using a finite element in a mixed formulation.

Space Truss Displacement Method for Plate-Cone Reticulated Shell

2013 ◽  
Vol 427-429 ◽  
pp. 7-9
Author(s):  
Xing Wang ◽  
Chao Feng ◽  
Nie Chen
Keyword(s):  
Mechanical Behavior ◽  
Double Layer ◽  
Space Structures ◽  
Displacement Method ◽  
Space Truss ◽  
New Type ◽  
Internal Forces

Plate-cone reticulated shell is a new type of space structures with good mechanical behavior and technical economy. In this dissertation, plate-cone reticulated shell is equated to double-layer reticulated shell with two kinds of material members. The internal forces and the displacement of plate-cone reticulated shell can be calculated by space truss displacement method.

Analysis of time-dependent effects in concrete structures using conventional linear computer programs

2001 ◽  
Vol 28 (2) ◽  
pp. 190-200 ◽  
Author(s):  
Mamdouh M Elbadry ◽  
Amin Ghali
Keyword(s):  
Prestressed Concrete ◽  
Precast Concrete ◽  
Concrete Structures ◽  
Computer Programs ◽  
Time Dependent ◽  
Analysis Computer ◽  
Internal Forces ◽  
Support Conditions ◽  
Creep And Shrinkage ◽  
Analysis Computer Program

Analysis of the time-dependent changes in displacements, internal forces, and reactions at the supports in continuous reinforced concrete structures cast, prestressed, and loaded at different stages is frequently needed in design to satisfy the serviceability requirements. The time-dependent parameters considered in the analysis are creep and shrinkage of concrete, relaxation of prestressed steel, sequence of construction, and changes in structural system and support conditions. A procedure of analysis is presented using conventional linear analysis computer programs. The analysis procedure is explained through examples to demonstrate its simplicity and applicability.Key words: analysis, computer program, creep, displacement, frames, precast concrete, prestressed concrete, relaxation, shrinkage, time-dependent.

Sign in / Sign up

Export Citation Format

Share Document