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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Excel Visual Basic Application ‘VBA’ for Beam problems Calculation
Abdalla Eissa Abdelkarim 1 *, Department of Civil Engineering Red Sea University
Abstract
VBA “Visual Basic Application” program run on EXCEL was written to solve the simple beam
problem which was divided into 100 segment to find shear, moment, slope and deflection at
each point. User inputs information into program: span load, span length, material properties,
concrete and steel strength. VBA program automatically calculates information and shows
results in a table and graphs.
Keywords: Excel VBA ,beam Bending,shear,slope deflection
1.IntroductionIn the past few years, spreadsheets have become a popular computational tool and a powerful platform for performing engineering calculations. Simplified program development and debugging,the use of named ranges and labels that enhance readability of formulas and ability to manipulate matrices aided this heightened popularity The
specific engineering programs are
licensed and hard to be installed in
every computer. But there is EXCEL
in every computer [1]. Spreadsheets
are characterised by arrays of cells in which data is input either as numbers or text or as formulae. Comments on data in the cells can also be input and hidden if desirable. Because of the mathematical nature of engineering studies, the use in which spreadsheet allows for numerical computations and for creation of good charts makes it the favourite tool for engineers [2]. It is, therefore, not surprising that it has become useful and inevitable tool in engineering education. Many studies have been performed to show the applications of spreadsheets in
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
engineering. A special issue of the International Journal of Engineering Education published in 2004 was dedicated fully to different forms of application of spreadsheets in engineering education. A comprehensive and instructive review was done by S.A. Oke of the University of Lagos in 2004 [3]. He credits electrical engineers for pioneering the use of spreadsheets in engineering education. Examples of researchers and practitioners in electromagnetism, logic networks, antenna design, microprocessor systems, Fourier series for harmonics analysis, etc, are given. In general engineering, numerical analysis, differentiation, integration and solution of partial differential equations are highlighted.In addition to the features and functions of Excel, its programming capabilities, called visual basic for applications (VBA) are very powerful and can be used to solve complex civil engineering problems [4]. To create VBA code, or to examine existing code, you will need to use
the Visual Basic Editor. To access the Visual Basic Editor in Excel 2013, we will go to file, options,customize ribbon and then select developer after that we click Visual Basic Editor from the submenu. The Visual Basic Editor screen usually contains three important windows: the Project Explorer window, the Properties window and the Code window, as shown in Figure 1.a,1.b,and 1.c rispectivly. The Code window displays the active module sheet; each module sheet can contain one or several VBA procedures. To insert a module sheet, choose Module from the Insert menu. A folder icon labeled Modules will be inserted; if you click on this icon, the module sheet Module1 will be displayed. To insert a module sheet, choose Module from the Insert menu. A folder icon labeled Modules will be inserted; if you click on this icon, the module sheet Module1 will be displayed. The Properties window will also displayed.
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Figure: 1.a. The Visual Basic Editor window.
Figure: 1.b The VBE Project Explorer window.
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Figure: 1.c The Properties window.
2.Method and procedureFirst of all in the workbook sheet (Fig. 2), user input the distributive load “w” in KN, span length in “m”, the beam breadth “B” in mm , the
beam overall depth “H” in mm , the reinforcement cover “C” in mm , the conctrte strength “fcu” in N/mm2,the reinforcement strength “fy” in N/mm2.
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Figure: .2 Beam input informations and table form
The VBA program figure (3) will use
this information to calculate forces,
deformations and reinforcement area
from start point “x” which is “0” to
the end point which is “L” and internal
points in between “98” points.
Figure: 3.a VBA program part 1
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Figure: 3.b VBA program part 2
The user click the calculate button to run the VBA program or information button to get more
informations about the program as shown in figure 4
Figure: 4 Information and calculated buttons
The calculated values of shear force V(x) , bending moment M(x) ,beam slope ϴ(x) and deflection
Y(x) are then tabulated as shown in figure 5.a, 5.b
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Figure: 5.a Tabulated results after depugging start from 0
Figure: 5.b Tabulated results after depugging end at L
The program also show the result in graphical state as shown in figures 6.a,6.b.6.c,6.d and 6.e
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Figure: 6.a shear force diagram
Figure: 6.b bending moment diagram
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
Figure: 6.c beam slope diagram
Figure: 6.d beam deflection diagram
ConclusionProgram shows the beam bending
calculation procedure of simply
supported problem very well. It
shows how to calculate beam forces
and deformations at 100 points beside
calculating steel reinforcement
according to BS8110 -97 along the
beam and compare it by minimum
area of steel that provided by the code
to get the maximum one .
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Red sea university Journal of Basic and Applied ScienceVol. 2 Special Issue (1) - March 2017
ISSN: 1858 -7690 (Online)ISSN: 1858 -7658 (Print)
References[1] Krudtong,S: Moaveni, S (2015)Teaching Tool: Finite Element Analysis of 2D Truss
Problem by VBA Program IJC, Vol.23 No.3 , pp. 89-91 90
[2]Bloch, S.C., EXCEL for Engineers and Scientists. John Wiley & Sons, Inc. (2003).
[3]Oke, S.A., Spreadsheet applications in engineering education: a review. Inter. J. of
Engng. Educ., 20, 6, 893-901(2004).
[4] E. Zaneldin, and B. El-Ariss, “Using Spreadsheets and VBA for Teaching Civil
Engineering Concepts,” J. Educat., Informatics and Cybernetics, Vol. 2, No. 1, 2011,
pp. 28-36.
[5] E. Joseph Billo, Excel for Scientists and Engineers Numerical Methods, John Wiley &
Sons,
2007.
[6] W.H.Mosley, J.H.Bungey. Reinforced concrete design, fourth edition , MACMILLAN
EDUCATION LTD,1990