The most common causes of unstable models are failing member nonlinearities such as tension members. As the simplest example, there is a frame with supports on the column footing and moment hinges on the column head. This unstable system is stabilized by a cross bracing of tension members. In the case of load combinations with horizontal loads, the system remains stable. However, if it is loaded vertically, both tension members fail and the system becomes unstable, which causes a calculation error. You can avoid such an error by selecting the exceptional handling of failing members under "Calculate" → "Calculation Parameters" → "Global Calculation Parameters".
The product range of Dlubal Software contains various modules for the design of steel and timber connections. The RF-/JOINTS Steel – Column Base add-on module allows you to analyze footings of hinged or restrained steel column bases. The fastener selection, foundation geometry, and material quality are crucial for the cost-effective and safe design of the column base.
A structural analysis does not only determine and design internal forces and deformations. It also ensures that the forces and moments in a structure are generated in a reliable way and applied to the foundation. Dlubal Software provides a wide range of products for the structural analysis and design of steel and timber connections. The RF-/JOINTS Steel – Column Base add-on module allows you to design footings of hinged and restrained column bases. The design can be performed for column base plates with or without stiffeners.
When designing column bases, high-performance anchors are often used for an anchorage. This article describes different models for a column footing and the evaluation thereof.