• Title/Summary/Keyword: Press bending

Search Result 1,659, Processing Time 0.022 seconds

Automatic generation of equilibrium and flexibility matrices for plate bending elements using Integrated Force Method

  • Dhananjaya, H.R.;Nagabhushanam, J.;Pandey, P.C.
    • Structural Engineering and Mechanics
    • /
    • v.30 no.4
    • /
    • pp.387-402
    • /
    • 2008
  • The Integrated Force Method (IFM) has been developed in recent years for the analysis of civil, mechanical and aerospace engineering structures. In this method all independent or internal forces are treated as unknown variables which are calculated by simultaneously imposing equations of equilibrium and compatibility conditions. The solution by IFM needs the computation of element equilibrium and flexibility matrices from the assumed displacement, stress-resultant fields and material properties. This paper presents a general purpose code for the automatic generation of element equilibrium and flexibility matrices for plate bending elements using the Integrated Force Method. Kirchhoff and the Mindlin-Reissner plate theories have been employed in the code. Paper illustrates development of element equilibrium and flexibility matrices for the Mindlin-Reissner theory based four node quadrilateral plate bending element using the Integrated Force Method.

A Study of punch and die plate for restriking mold of structure engineering design (리스트라이킹 금형용 펀치와 다이플레이트의 구조 설계에 관한 연구)

  • Kim, Sei-Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.8 no.4
    • /
    • pp.708-712
    • /
    • 2007
  • Restriking is a shaping method added to the processed products to get higher precision and accuracy in the press die process. This method is frequently used in bending works and drawing works. The purpose of this research is to develop a design for rectangular drawing die punch and die block form which enables drawing formation and restriking in one set.

  • PDF

Bending response of functionally graded piezoelectric plates using a two-variable shear deformation theory

  • Zenkour, Ashraf M.;Hafed, Zahra S.
    • Advances in aircraft and spacecraft science
    • /
    • v.7 no.2
    • /
    • pp.115-134
    • /
    • 2020
  • This paper proposes a bending analysis for a functionally graded piezoelectric (FGP) plate through utilizing a two-variable shear deformation plate theory under simply-supported edge conditions. The number of unknown functions used in this theory is only four. The electric potential distribution is assumed to be a combination of a cosine function along the cartesian coordinate. Applying the analytical solutions of FGP plate by using Navier's approach and the principle of virtual work, the equilibrium equations are derived. The paper also discusses thoroughly the impact of applied electric voltage, plate's aspect ratio, thickness ratio and inhomogeneity parameter. Results are compared with the analytical solution obtained by classical plate theory, first-order-shear deformation theory, higher-order shear deformation plate theories and quasi-three-dimensional sinusoidal shear deformation plate theory.

Elastic bending analysis of irregular-shaped plates

  • Sakiyama, T.;Huang, M.
    • Structural Engineering and Mechanics
    • /
    • v.7 no.3
    • /
    • pp.289-302
    • /
    • 1999
  • An approximate method for analyzing the bending problems of irregular-shaped plates is proposed. In this paper irregular-shaped plates are such plates as plate with opening, circular plate, semi-circular plate, elliptic plate, triangular plate, skew plate, rhombic plate, trapezoidal plate or the other polygonal plates which are not uniform rectangular plates. It is shown that these irregular-shaped plates can be considered finally as a kind of rectangular plates with non-uniform thickness. An opening in a plate can be considered as an extremely thin part of the plate, and a non-rectangular plate can be translated into a circumscribed rectangular plate whose additional parts are extremely thin or thick according to the boundary conditions of the original plate. Therefore any irregular-shaped plate can be replaced by the equivalent rectangular plate with non-uniform thickness. For various types of irregular-shaped plates the convergency and accuracy of numerical solution by proposed method are investigated.

Endochronic prediction for the mechanical ratchetting of a stepped beam subjected to steady tension and cyclic bending

  • Pan, W. F.;Yang, Y. S.;Lu, J. K.
    • Structural Engineering and Mechanics
    • /
    • v.6 no.3
    • /
    • pp.327-337
    • /
    • 1998
  • In this paper, the first-order ordinary differential constitutive equations of endochronic theory are incorporated into finite element formalism. A theoretical investigation is performed on the ratchetting effect of a stepped beam subjected to steady tension and cyclic bending. Experimental data of lead alloy found in literature are used for comparison. Those data reveal that the endochronic prediction yields more adequate results than those predictions using the plasticity models with isotropic hardening or kinematic hardening, as employed by Hardy, et al. (1985).

Ultimate flexural and shear capacity of concrete beams with corroded reinforcement

  • Bhargava, Kapilesh;Ghosh, A.K.;Mori, Yasuhiro;Ramanujam, S.
    • Structural Engineering and Mechanics
    • /
    • v.27 no.3
    • /
    • pp.347-363
    • /
    • 2007
  • Assessment of structural behaviour of corrosion affected structures is an important issue, which would help in making certain decisions pertaining to the inspection, repair, strengthening, replacement and demolition of such structures. The paper presents formulations to predict the loss of weight and the loss of cross-sectional area of the reinforcing bar undergoing corrosion based on the earlier study carried out by the present authors (Bhargava et al. 2006). These formulations have further been used to analytically evaluate the ultimate bending moment and ultimate shear force capacity of the corroded concrete beams. Results of the present study indicate that, a considerably good agreement has been observed between the experimental and the analytically predicted values for the weight loss and reduction in radius of the corroded reinforcing bars. A considerably good agreement has also been observed between the experimental and the analytically predicted values of ultimate bending moment and ultimate shear force capacity for the corroded concrete beams.

A semi-analytical FE method for the 3D bending analysis of nonhomogeneous orthotropic toroidal shells

  • Wu, Chih-Ping;Li, En
    • Steel and Composite Structures
    • /
    • v.39 no.3
    • /
    • pp.291-306
    • /
    • 2021
  • Based on Reissner's mixed variational theorem (RMVT), the authors develop a semi-analytical finite element (FE) method for a three-dimensional (3D) bending analysis of nonhomogeneous orthotropic, complete and incomplete toroidal shells subjected to uniformly-distributed loads. In this formulation, the toroidal shell is divided into several finite annular prisms (FAPs) with quadrilateral cross-sections, where trigonometric functions and serendipity polynomials are used to interpolate the circumferential direction and meridian-radial surface variations in the primary field variables of each individual prism, respectively. The material properties of the toroidal shell are considered to be nonhomogeneous orthotropic over the meridianradial surface, such that homogeneous isotropic toroidal shells, laminated cross-ply toroidal shells, and single- and bi-directional functionally graded toroidal shells can be included as special cases in this work. Implementation of the current FAP methods shows that their solutions converge rapidly, and the convergent FAP solutions closely agree with the 3D elasticity solutions available in the literature.

Flexural studies on reinforced geopolymer concrete beams under pure bending

  • Sreenivasulu, C.;Jawahar, J. Guru;Sashidhar, C.
    • Advances in concrete construction
    • /
    • v.8 no.1
    • /
    • pp.33-37
    • /
    • 2019
  • The present investigation is mainly focused on studying the flexural behavior of reinforced geopolymer concrete (RGPC) beams under pure bending. In this study, copper slag (CS) was used as a partial replacement of fine aggregate. Sand and CS were blended in different proportions (100:0, 80:20, 60:40 and 40:60) (sand:CS) by weight. Fly ash and ground granulated blast furnace slag (GGBS) were used as binders and combination of sodium hydroxide (8M) and sodium silicate solution were used for activating the binders. The reinforcement of RGPC beam was designed as per guidelines given in the IS 456-2000 and tested under pure bending (two-point loading) after 28 days of ambient curing. After conducting two point load test the flexural parameters viz., moment carrying capacity, ultimate load, service load, cracking moment, cracking load, crack pattern and ultimate deflection were studied. From the results, it is concluded that RGPC beams have shown better performance up to 60% of CS replacement.

Static analysis of laminated piezo-magnetic size-dependent curved beam based on modified couple stress theory

  • Arefi, M.
    • Structural Engineering and Mechanics
    • /
    • v.69 no.2
    • /
    • pp.145-153
    • /
    • 2019
  • Modified couple stress formulation and first order shear deformation theory are used for magneto-electro-elastic bending analysis of three-layered curved size-dependent beam subjected to mechanical, magnetic and electrical loads. The governing equations are derived using a displacement field including radial and transverse displacements of middle surface and a rotation component. Size dependency is accounted based on modified couple stress theory by employing a small scale parameter. The numerical results are presented to study the influence of small scale parameter, initial electric and magnetic potentials and opening angle on the magneto-electro-elastic bending results of curved micro beam.

Size dependent dynamic bending nonlocal response of armchair and chiral SWCNTs based on Flügge model

  • Hussain, Muzamal
    • Advances in concrete construction
    • /
    • v.13 no.6
    • /
    • pp.451-459
    • /
    • 2022
  • In present study, the nonlocal Flügge shell model based is utilized to investigate the vibration characteristics of armchair and chiral single-walled carbon nanotubes with impact of small-scale effect subjected to two boundary supports. The wave propagation approach is employed to determine eigen frequencies for armchair and chiral tubes. The fundamental frequencies scrutinized with assorted aspect ratios by varying the bending rigidity. The raised in value of nonlocal parameter reduces the corresponding fundamental frequency. It is investigated with higher aspect ratio, the boundary conditions have a momentous influence on vibration of CNT. It is concluded that frequencies would increase by increasing of the bending rigidity. Solutions of the frequency equation have determined by writing in MATLAB coding.