Questions: 1) Encuentre las fuerzas en los elementos DF, DG y EG. (100 puntos). a. Considere el soporte A de tipo 1 y el soporte L de tipo 2.

Solution Steps

• Identify the type of supports: A is a pin support and L is a roller support.
• Calculate the reactions at supports A and L using equilibrium equations.
• Sum of vertical forces: \( \sum F_y = 0 \)
• Sum of horizontal forces: \( \sum F_x = 0 \)
• Sum of moments about point A: \( \sum M_A = 0 \)

• Sum of vertical forces: \( R_A + R_L = 4 \times 1.2 \text{ kN} = 4.8 \text{ kN} \)
• Sum of moments about A: \( R_L \times 18.5 \text{ m} = 1.2 \text{ kN} \times (2.25 + 4) \text{ m} + 1.2 \text{ kN} \times (2.25 + 8) \text{ m} + 1.2 \text{ kN} \times (2.25 + 12) \text{ m} + 1.2 \text{ kN} \times (2.25 + 16) \text{ m} \)
• Solve for \( R_L \): \( R_L = \frac{1.2 \times 6.25 + 1.2 \times 10.25 + 1.2 \times 14.25 + 1.2 \times 18.25}{18.5} \)
• Calculate \( R_A \): \( R_A = 4.8 \text{ kN} - R_L \)

• Start with joint A or L where there are fewer unknowns.
• Use equilibrium equations for each joint: \( \sum F_x = 0 \) and \( \sum F_y = 0 \)
• Solve for the forces in members DF, DG, and EG.

Final Answer