Author(s)

Zhonghu Zhao ¹, Boqian Xue ¹

Affiliation(s)

¹ College of Civil Engineering and Mechanics, Lanzhou University, Lanzhou, Gansu, 730000, China

Corresponding Author

Zhonghu Zhao

ABSTRACT

Due to the varying conventions for determining the sign of bending moments across different mechanics courses, particularly in elasticity mechanics where there are no clear guidelines, beginners often find themselves confused during the learning process. This inconsistency not only increases the difficulty of learning but also leads to confusion when students study across multiple disciplines. This paper analyzes and summarizes the sign conventions of various mechanical quantities and their interrelationships in different mechanics courses. By comparing the sign conventions of bending moments in these courses, this paper proposes a unified method for sign determination applicable to all of them and further validates the method's reasonableness and applicability through specific examples. Although researchers in recent years have proposed different methods for determining bending moments within specific disciplines, no one has yet introduced a theory that unifies the sign determination of bending moments across theoretical mechanics, structural mechanics, material mechanics, and elasticity mechanics. The findings of this research provide valuable insights for the teaching of mechanics courses.

KEYWORDS

Elastic Mechanics, Teach, Bending Moment, Sign, Judgment Method

CITE THIS PAPER

Zhonghu Zhao, Boqian Xue, A Unified Method for Determining the Sign Convention of Bending Moments in Mechanics Courses. Journal of Precision Instrument and Machinery (2024) Vol. 4: 12-19. DOI: http://dx.doi.org/10.23977/jpim.2024.040103.

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