1. What is Ground Bearing Pressure?

Ground Bearing Pressure (GBP) is the average pressure exerted by a crane or heavy equipment on the ground surface. It's a critical factor in determining whether the ground can safely support the equipment without risk of sinking or instability.

2. How Does the Calculator Work?

The calculator uses the Ground Bearing Pressure formula:

Where:

• \( GBP \) — Ground Bearing Pressure (kPa)
• \( Total\ Weight \) — Total weight of the crane including counterweights and load (kg)
• \( Contact\ Area \) — Total area of contact between outriggers/crawlers and ground (m²)

Explanation: The formula calculates the pressure distribution by dividing the total weight by the contact area with the ground.

3. Importance of GBP Calculation

Details: Accurate GBP calculation is essential for crane setup safety. It helps determine if additional ground protection (mats, cribbing) is needed and ensures the crane operates within the ground's load-bearing capacity.

4. Using the Calculator

Tips: Enter the total weight in kilograms and contact area in square meters. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is a safe GBP value for typical ground conditions?
A: Safe GBP values vary by soil type. Generally, 50-100 kPa is safe for firm ground, while soft ground may require less than 25 kPa.

Q2: How do I measure contact area for crawler cranes?
A: For crawler cranes, measure the length and width of each crawler pad and multiply to get area, then sum both crawlers.

Q3: Does the load weight include the crane's own weight?
A: Yes, total weight includes the crane's weight, counterweights, and any lifted load.

Q4: What factors affect ground bearing capacity?
A: Soil type, moisture content, compaction, and recent weather conditions all significantly impact ground bearing capacity.

Q5: When should I use ground protection mats?
A: Use mats when calculated GBP exceeds the safe bearing capacity of the ground or when working on sensitive surfaces like asphalt or concrete.