Lecture 8 part II

Lecture 8 part II - PART II Contents PLANE TRUSSES (Cont) o...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
9 PART II Contents PLANE TRUSSES (Cont’) o Method of joints o Zero-force members o Method of sections o Forces in straight and curved two-force members
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
10 Method of joints Since when a truss is a rigid body in equilibrium, each part must be in equilibrium. Then the forces on the joint are concurrent forces. The method of joints consists of taking the truss apart; drawing separate FBD of each part –each member and each pin, and applying the equations of equilibrium of each part of the truss in turn. An FBD having only axial forces applied to their ends because of the assumptions about how a truss is constructed and loaded. The force in each member is determined as the magnitude and the sense of the force is decided . In the FBD, all member forces are suggested to be drawn as tensile forces . A negative value for a force in the solution will indicate that the member was really in compression. The forces exerted on a member by a pin and exerted on a pin by a member are equal and opposite . The equilibrium of the joints in the truss is expressed by drawing a separate FBD for each joint in terms of 0 x = F 0 y = F (3) Thus, there will be 2 j independent scalar equations available. This is precisely the number of independent equations needed to solve for the m member forces and 3 support reactions of a simple truss. This is a simple truss with five members and four joints.
Background image of page 2
11 The corresponding exploded set of FBD’s are
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
12 Example 7.1 FBD #1
Background image of page 4
13 Example 7.4 FBD #1
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
14 Example 7.5 FBD #1
Background image of page 6
15 Example 7.6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/20/2009 for the course CVEN 221 taught by Professor - during the Summer '08 term at Texas A&M.

Page1 / 22

Lecture 8 part II - PART II Contents PLANE TRUSSES (Cont) o...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online