Computation of Optimal Cross Section of Gravity Dams Using Genetic Algorithms | Chapter 1 | Current Overview on Science and Technology Research Vol. 6

 The construction of gravity dams uses an interactive method involving preliminary layout of the structure followed by stability and stress studies. In this study, we present a method to define the optimal cross-sectional area of ​​weight dams determined using genetic algorithms. To solve the optimization task (minimization of dumb costs), an optimization routine based on genetic algorithms (GA) was implemented in a Microsoft Excel spreadsheet. It proved adequate and the GA parameters were optimized in a parametric study. Using the parameters found in the parametric study, we determined the top width of the heavy wall and compared it with the slope-based optimization method (traditional method). The agreement between the two approaches was excellent. For the optimal dam cross-section, the ratio of dam base to dam height is ~0.85 and the ratio of dam crest width to dam height is ~0.13. This computational approach allows the calculation of the optimal top width for a wide range of gravity dam heights.

Author(s) Details:

Farzin Salmasi,
Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.

John Abraham,
University of St. Thomas, Minnesota, School of Engineering 2115 Summit Avenue St. Paul, Minnesota 55105, USA.

Please see the link here: https://stm.bookpi.org/COSTR-V6/article/view/8411

Advanced Numerical Techniques for Strength Prediction of Adhesive Joints under Peel Loadings | Chapter 1 | Research Developments in Science and Technology Vol. 7

 Adhesive bonding is becoming more popular for structural applications due to benefits such as more uniform stress distributions and the ease with which diverse materials may be joined. There are many different types of joint architectures, but the most prevalent are single-lap joints (SLJ), double-lap joints, and scarf joints. T-joints are used in aeroplanes to attach stiffeners to the skin and in automobiles to connect the B-pillar and the rocker, although they are rarely examined in the literature. Different forecasting approaches for these joints are available in the literature, however some of them only operate for certain joint types. The performance of the structural adhesive Araldite® 2015 in an aluminium T-joint is quantitatively evaluated using cohesive zone modelling (CZM). Following CZM validation with experimental findings utilising a comparable geometry, this approach was able to be used in a later numerical research. The behaviour of several T-joint geometrical configurations when subjected to peel stresses is then captured using a solely CZM numerical analysis. A parametric research is included in the work, which involves stress analysis in the elastic loading stage and maximum load (Pm) prediction using four geometrical parameters: flat adherend thickness (a), T-element thickness (t), overlap length (l), and T-element radius (r). The examined factors had a substantial influence on Pm, and the CZM approach proved to be a precise method for investigating T joints with precision and accuracy.

Author(s) Details:

J. P. M. Lopes,
Departamento de Engenharia Mecânica, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Rua Dr. António Bernardino de Almeida, 431, 4200-072 Porto, Portugal.

R. D. S. G. Campilho,
INEGI – Pólo FEUP, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal.

R. J. B. Rocha,
Departamento de Engenharia Mecânica, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Rua Dr. António Bernardino de Almeida, 431, 4200-072 Porto, Portugal.

I. J. Sanchez-Arce,
INEGI – Pólo FEUP, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal.

Please see the link here: https://stm.bookpi.org/RDST-V7/article/view/7073

Application of Advanced Numerical Techniques for the Analysis Tubular Adhesive Joints | Chapter 12 | Technological Innovation in Engineering Research Vol. 3

Because of its advantages over mechanically attached or welded connections, adhesive joints have been used in a variety of industries. Adhesive joints offer more strength, are lighter, and are easier to manufacture. A parametric analysis of the tensile strength of single-lap tubular adhesive joints bonded with three adhesives (Araldite® AV138, Araldite® 2015, and Sikaforce® 7752) and various overlap lengths is presented in this paper (LO). The major goal of this study is to compare the strength prediction abilities of the eXtended Finite Element Method (XFEM) with experimental data. There is also a comparison of the findings obtained using Cohesive Zone Models (CZM). The parametric numerical research also provides for a critical assessment of the adhesives' performance in this sort of joint. the dissipated energy (Ediss) and the distribution of peel (y) and shear stresses (xy) for LO=20 and 40 mm during simulations till failure. When the damage initiation and propagation parameters were selected appropriately, the XFEM was proven to be a viable and accurate approach for tubular joint strength prediction.

Author(s) Details:

S. M. L. Eusebio,
Departamento de Engenharia Mecânica, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, R. Dr. António Bernardino de Almeida, 431, 4200-072 Porto, Portugal.

R. D. S. G. Campilho,
Departamento de Engenharia Mecânica, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, R. Dr. António Bernardino de Almeida, 431, 4200-072 Porto, Portugal and  INEGI – Pólo FEUP, Rua Dr. Roberto Frias, 400, 4200-465 Porto, Portugal.

Please see the link here: https://stm.bookpi.org/TIER-V3/article/view/7070