1. What is Lag Load Capacity?

Lag load capacity refers to the maximum load that a lag screw or bolt can support when subjected to withdrawal forces. It's an important calculation in construction and engineering to ensure structural integrity and safety.

2. How Does the Calculator Work?

The calculator uses the lag load capacity formula:

Where:

• Withdrawal Strength — The force per unit length the material can withstand (lb/in)
• Length — The embedded length of the lag screw (in)
• Diameter — The diameter of the lag screw (in)

Explanation: The equation calculates the total withdrawal capacity by multiplying the material's withdrawal strength by both the length and diameter of the lag screw.

3. Importance of Lag Load Capacity Calculation

Details: Accurate lag load capacity calculation is crucial for structural safety, preventing fastener failure, and ensuring proper load distribution in construction projects.

4. Using the Calculator

Tips: Enter withdrawal strength in lb/in, length in inches, and diameter in inches. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What factors affect withdrawal strength?
A: Withdrawal strength depends on the wood species, moisture content, screw type, and thread design.

Q2: How does screw diameter affect capacity?
A: Larger diameter screws have greater surface area and typically higher withdrawal capacity.

Q3: What is a typical withdrawal strength value?
A: Withdrawal strength varies by material but typically ranges from 100-500 lb/in for wood screws in various wood types.

Q4: Are there safety factors to consider?
A: Yes, most engineering applications use safety factors of 2-4x the calculated capacity for critical structural elements.

Q5: Does screw spacing affect capacity?
A: Yes, screws placed too close together may reduce overall capacity due to wood splitting or reduced material strength between fasteners.