Shaking table investigation of a low-cost and sustainable timber-based energy dissipation system with recentering ability

Abstract

The aim of this paper is to demonstrate the efficiency of a low-cost and sustainable timber-based energy dissipation system with recentering ability, which can be used as a seismic isolation system or a tuned mass damper for the seismic protection of structures in developing or developed countries. The system, defined as Dovetail with SPrings (Dove-SP), utilizes the attractive properties of timber to store CO2, thus reducing the carbon footprint of the existing energy dissipation systems: It comprises two timber slabs that are designed to slide against each other in a motion that is restrained by a dovetail sliding joint. Two sliding interfaces that allow this sliding motion at an attractively low friction coefficient are experimentally investigated: A PVC sand-wich (PVC-s) sliding interface, comprising a thin layer of sand that is sand-wiched between two PVC layers and a timber sand-wich sliding interface consisting of a thin layer of sand encapsulated between two beech timber surfaces. A set of low-cost steel springs is designed and installed on both sides of the dovetail joint to recenter the structure back to its original position after the end of an earthquake ground motion excitation. A novel, low-cost and deformable wood material fabricated from delignified balsa wood is used to reduce the pounding effects before the activation of the steel springs. The seismic behavior and the recentering ability of the novel timber-based energy dissipation system subjected to an ensemble of recorded earthquake ground motion excitations was experimentally investigated through a large-scale shaking table investigation at ETH Zurich.