Modular Timber Buildings Show Resilience in Earthquake Tests

Recent large-scale earthquake tests have evaluated an innovative timber-based building technology designed to enhance structural resilience and minimize post-event damage. The system utilizes cross-laminated timber (CLT), a material made by bonding layers of timber boards at right angles to create large structural panels. CLT is a renewable material that stores carbon and offers lower embodied emissions compared to traditional concrete and steel.

The developed system allows individual stories of a building to move independently during seismic events, rather than forcing the entire structure to act as a rigid unit. This controlled movement aims to reduce strain on the building and facilitate its return to its original position once shaking ceases. This "self-centering" capability is crucial for minimizing damage and enabling a quicker return to usability after an earthquake.

To validate the system, a full-scale, two-story modular CLT building was tested on the University of Auckland's shake table. Additional weight was applied to simulate the forces experienced by a typical three-story structure. The building was subjected to a series of increasingly intense earthquake simulations, replicating both distant and near-source seismic events.

The test building performed as expected, with the connection system enabling controlled story movement that absorbed and dissipated energy. Crucially, the main timber structure remained undamaged, and the building returned to its original position after the shaking subsided. While the test did not assess nonstructural elements, the results suggest modular timber buildings can be designed to withstand and recover from major earthquakes with minimal damage.