Structural Utilization Calculator

About the Structural Utilization Calculator

Calculates the utilization ratio of a structural member by comparing the applied load (demand) to its capacity, flagging the safety status.

How to use this calculator

1. Enter the demand, which is the load effect you want to check, such as force, moment, or stress.
2. Enter the capacity, which is the maximum value the member can safely resist in the same units.
3. The calculator divides demand by capacity and multiplies by \(100\) to give utilization as a percentage.
4. Review the result, where values below \(100\\%\) mean demand is within capacity and values above \(100\\%\) mean demand exceeds capacity.

The formula explained

The formula \( utilization = \frac{demand}{capacity} \times 100 \) computes the utilization percentage. It shows the share of capacity being used by the applied demand.

• utilization = the percentage of capacity being used
• demand = the applied load effect or required resistance
• capacity = the available member capacity

Step by step method

1. Take the demand and the capacity in matching units.
2. Divide the demand by the capacity to get a decimal ratio.
3. Multiply the ratio by \(100\) to convert it to a percent.

Worked example

Problem. A beam has a demand of \(180\) kN and a capacity of \(240\) kN. Find the structural utilization.

1. Use the formula \( utilization = \frac{demand}{capacity} \times 100 \).
2. Substitute the values, \( utilization = \frac{180}{240} \times 100 \).
3. Compute \( \frac{180}{240} = 0.75 \), so \( utilization = 75\\% \).

Tips and common mistakes

• Make sure demand and capacity use the same units before calculating, otherwise the percentage is not meaningful.
• A result of \(100\\%\) means full utilization, so values above that indicate the demand is greater than the stated capacity.

Frequently asked questions