Asee peer logo

Four Point Bending: A New Look

Download Paper |


2002 Annual Conference


Montreal, Canada

Publication Date

June 16, 2002

Start Date

June 16, 2002

End Date

June 19, 2002



Conference Session

Innovative Lab and Hands-on Projects

Page Count


Page Numbers

7.574.1 - 7.574.12



Permanent URL

Download Count


Request a correction

Paper Authors

author page

William Szaroletta

author page

Nancy Denton

Download Paper |

NOTE: The first page of text has been automatically extracted and included below in lieu of an abstract

Main Menu Session 2168

Four Point Bending: A New Look

William K. Szaroletta, Nancy L. Denton Purdue University, West Lafayette, Indiana

Abstract: Four point bending (FPB) is a cornerstone element of the beam flexure portion of a sophomore- level mechanics of materials course. The FPB lecture has traditionally developed the theory from free body diagram through beam deflection, with related homework problems providing analytical practice. Similarly, the FPB laboratory, which has been essentially unchanged for nearly two decades, has provided students an opportunity to experimentally and analytically verify and validate beam flexure theory. Although excellent correlation between theoretical and experimental results was frequently obtained, hardware requirements have limited the accuracy and amount of data that collected within a standard 110-minute laboratory session.

Recent FPB laboratory upgrades utilizing data acquisition (DAQ) hardware and software have enabled the students to test a much larger sample of beams in roughly the same timeframe with increased repeatability. The DAQ upgrade has facilitated increased understanding of flexural theory, introduced modern experimental methods in both lecture and laboratory, given students a more robust data set upon which to base their analyses, and enhanced student experiences with technical report writing. This paper includes an overview of FPB theory, analysis techniques, and traditional laboratory procedures, and details the success of the FPB DAQ upgrade, operation, and outputs.

Introduction: Beam flexure represents one of the three most common loading categories for mechanical systems. As such, it is on the syllabi of nearly all sophomore-level mechanics of materials courses, including the mechanical engineering technology course under consideration here. Within the lecture setting, FPB theory is developed from free-body diagram through beam deflection. Theory is reinforced by analytical practice solving related homework problems 1-3. The corresponding FPB laboratory has afforded students the opportunity to experimentally and analytically verify and validate beam flexure theory3. Excellent correlation between theoretical and experimental results is often obtained. However, the person-centered, primarily analog method used for acquiring, recording, and analyzing the data is cumbersome and frustrating for the students. The accuracy and amount of data that can be collected within a standard 110-minute laboratory session has been limited, as has the extent of the analysis that seems reasonable to require.

To address student dissatisfaction with the FPB laboratory, a revision was deemed desirable. The implemented revision was designed to accommodate faculty concerns that the students have a laboratory experience that mirrors the industrial laboratory and obtain additional practice manipulating experimental data. Thus, the FPB laboratory has recently been upgraded through the inclusion of automated data acquisition (DAQ) hardware and software. This upgrade has

Proceedings of the 2002 American Society for Engineering Education Annual Conference & Exposition Copyright Ó 2002, American Society for Engineering Education

Main Menu

Szaroletta, W., & Denton, N. (2002, June), Four Point Bending: A New Look Paper presented at 2002 Annual Conference, Montreal, Canada. 10.18260/1-2--11349

ASEE holds the copyright on this document. It may be read by the public free of charge. Authors may archive their work on personal websites or in institutional repositories with the following citation: © 2002 American Society for Engineering Education. Other scholars may excerpt or quote from these materials with the same citation. When excerpting or quoting from Conference Proceedings, authors should, in addition to noting the ASEE copyright, list all the original authors and their institutions and name the host city of the conference. - Last updated April 1, 2015