Hybrid Simulation of Thermomechanical Structural Response

Abstract

A new thermomechanical hybrid simulation method is proposed that extends the mechanical hybrid simulation method by including thermal degrees of freedom and temperature loads. The thermomechanical hybrid simulation method was implemented in the OpenSees and OpenFresco frameworks. Modifications to enable this new capability centered on incorporating the temperature degrees of freedom in the hybrid model domain, and on developing new OpenFresco objects and a test execution strategy to simultaneously control the structural elements of the experimental setup, the thermal loads, and the mechanical loads. The implementation of the thermomechanical method at the ETH Zürich IBK Structural Testing Laboratory was verified and validated using a simple two-element hybrid model. The responses of the model to a force ramp, applied to the full structure, and a scaled version of the ISO 834 standard fire curve, applied to the experimental element, were obtained in two simulations—one conducted using an explicit and the other using an implicit integration scheme. The tests yield very similar results, and both simulations closely match the theoretical solution.