This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: CE 3101 Fall 2011 Homework 08 - Mohr’s Circle for Plane Stress Due Thursday, 3 November 2011, 11:55 P.M. This is an INDIVIDUAL assignment. Abstract As INDIVIDUAL students 1 , you will design and implement a MATLAB function to compute and plot Mohr’s Circle for Plane Stress . A brief letter report is required in addition to the working, well-documented, code. A full written report is NOT requested or required. Evaluation and the Time Card After completing this assignment you are each required to INDIVIDUALLY complete the Homework 08 Evaluation , found on the course Moodle web site. Your evaluation activity must be completed by 6:00 P.M., Friday, 4 November 2011, or you risk the imposition of an egregious 5-point penalty. 1 Background Mohr’s circle 2 is a graphical presentation of the two-dimensional state of stress at a point. The representation was proposed in 1892 by Christian Otto Mohr 3 (1835-1918). If you do not yet know “Mohr’s circle” from other classes, you soon will, for it is a useful visualization tool used in many classes, including deformable body mechanics, civil engineering materials, soil mechanics, rock mechanics, and linear structural analysis, to name a few in the CE Department. Mohr’s circle is also used in MatS courses like the science of engineering materials and the associated lab. In short, Mohr’s circle is your friend. 2 Problem Write a MATLAB routine called “ MohrsCircle2D ” (the associated file will be named MohrsCicrle2D.m ) that takes three input arguments σ X , σ Y , and τ XY , draws the associated Mohr’s Circle diagram 4 for plane stress (i.e. 2D), and returns the two principal stresses and the maximum shear stress. • You will need to draw a circle, probably using the plot command. Fill in the circle with a light or pastel color. • Please make certain that you draw a circle and not an ellipse; to do this you will need to investigate the axis equal command. • You may also want to increase the plot margins beyond the default. To do this you will probably use the axis command 5 . • You will need to label the axes. The difficulty with this is that you need to draw the Greek characters τ and σ . Fortunately, MATLAB can do this nicely 6 . Use a larger text size than the default. • Plot and annotate (with the input numeric values) the points on the circle represented by the input stresses: ( σ x ,- τ xy ) and ( σ y , τ xy ) . You will probably need to use the plot command, and the sprintf and text commands. Draw a colored 7 line connecting these two points. 1 You may work together, help each other out, swap ideas and code fragments, carry on open discussions on the forum, but every individual is responsible for their own submission....
View Full Document
- Spring '11
- Shear Stress, principal stresses, title block, Deformable Body Mechanics