Free Bachelor of Civil Engineering Structural Analysis Questions and Answers

Question 1

Which one of the subsequent structural loads is not frequently applied to a building?

Accepted Answer

Rain load

Answer

While rain can contribute to live loads on roofs (e.g., ponding water), a distinct 'rain load' is not typically classified as a primary, frequently applied structural load category in the same way as dead, live, or environmental loads (like wind or seismic). Its effects are usually accounted for within the general live load provisions or through proper drainage design, rather than as a separate, major load case for general building structures.

Question 2

What is the maximum permissible decrease percent in the case of a structural member supporting more than one level with a load above 100psf?

Accepted Answer

20

Answer

Building codes allow for live load reductions on structural members supporting large tributary areas or multiple floors, as the probability of the entire area experiencing the full design live load simultaneously is low. However, for members supporting more than one level with a significant load (above 100 psf), a maximum permissible reduction is often capped. This 20% limit ensures a conservative design, preventing excessive reduction that could compromise safety even if the standard reduction formula might yield a higher value.

Question 3

Which of the following structures is statically determined?

Accepted Answer

Double overhanging

Answer

A statically determinate structure is one where all unknown reactions and internal forces can be determined solely using the equations of static equilibrium. A double overhanging beam, when supported by two simple supports, has exactly three unknown reactions (two vertical reactions and one horizontal reaction if applicable), which can be solved using the three equilibrium equations (sum of forces in x, y, and sum of moments). In contrast, fixed beams, two-hinged arches, and continuous beams typically have more unknowns than equilibrium equations, making them statically indeterminate.

Question 4

What is the load factor for H in the equation U-0.9D + 1.6W + 1.6H if H's structural action cancels out W's or E's?

Accepted Answer

0

Answer

In Load and Resistance Factor Design (LRFD), load factors are applied to nominal loads. If a load (H) has a structural action that counteracts or reduces the effect of other primary loads (like wind W or earthquake E), it is considered a beneficial load in that specific load combination. To ensure a conservative design, the load factor for such beneficial loads is typically taken as 0, meaning its positive contribution is ignored to design for the worst-case scenario.

Question 5

If the hospital is constructed of structural steel frames, what will be the value of Vmax in the previous question?

Accepted Answer

.02813gw

Answer

The value Vmax represents the maximum base shear in seismic design, which is the total lateral force at the base of a structure due to an earthquake. For a hospital, classified as an essential facility, and constructed with structural steel frames, specific seismic design parameters and formulas from building codes (e.g., ASCE 7) are used. The coefficient 0.02813 would be derived from factors like the seismic response coefficient, importance factor, and structural system response modification factor, specific to such a building type and location, when multiplied by the total effective seismic weight (gw).

BCE - Bachelor of Civil Engineering Practice Test

BCE - Bachelor of Civil Engineering Practice Test

Free Bachelor of Civil Engineering Structural Analysis Questions and Answers