Ground bearing pressure
Also called Bearing pressure, GBP
The load per unit area transmitted from a foundation, outrigger, track or mat down into the supporting ground, usually expressed in kilonewtons per square metre (kN/m²). Comparing the applied bearing pressure against the ground’s bearing capacity is the basic calculation behind every ground protection decision.
From our specifications
Plan area is the only term in that comparison a mat supplier controls. Our 25 ALIMATS® configurations span 1.346 m² to 8.074 m² of plan area — a sixfold range — so the same outrigger reaction can be delivered to the ground at a sixth of the pressure by changing nothing but what sits under the foot.
Source: alimat_configurations — the 25 published ALIMATS® configurations
Where it matters on site
The applied figure and the allowable figure come from different places and often from different people: the applied pressure is derived from the crane’s load chart and its outrigger reactions, while the allowable pressure comes from the ground investigation, or from the design of an engineered working platform. Where nobody owns both numbers, they frequently never get compared. Note also that kN/m² and kPa are the same unit, which matters when a figure has been lifted from a manufacturer’s literature written for another market.