CE 3404: Introduction to Structural Engineering
Homework #4 – Beams
Due: Friday, Feb 28 at 11:59 PM (through Gradescope)
Office hours: Tue: 11 – 12 PM & Thu: 2 – 3 PM (102B Patton Hall)
Spring 2025
1. Determine if each of the following structures is stable. If so, determine if the structure is statically
determinate, or indeterminate. If indeterminate, identify the degree of static indeterminacy. (5 points)
2. Wood beams cantilevered out from a house to form an elevated deck. The owners wanted a bigger deck, so
they extended the beams and added columns at the far ends. The addition was not engineered, so the owners have
no idea whether the deck is safe. Now that they want to sell the house, they have hired your firm to evaluate the
capacity of the deck in its current condition. As part of that evaluation, you need to know the internal forces
generated by the full live load. (20 points)
(a) Construct the shear force and bending moment diagrams for the beam using both the equation method and the
area method (Use the figure on page 2 as a guide to calculate reactions) (14 points)
(b) Identify at least two features of the shear diagram that suggest you have a reasonable answer (see page 3 for
examples) (2 points)
(c) Identify at least two features of the BM diagram that suggest you have a reasonable answer (see page 3 for
examples). (2 points)
(d) Determine the maximum bending moment and its location. (2 points)
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