Recently, from viewpoint of Global Environment, timber, i.e., one of nature cycle materials, has been tried to be utilized as structural members of large timber buildings in Europe and North America. A representative timber of the members is Cross-laminated timber (CLT), however, CLT structural system very often restricts planning of building because of CLT being plate member. High-stiffness-strength-timber slender beam and column are significantly desired.

This study focuses a hybrid glulam timber with steel deformed bar (rebar) and Epoxy resin adhesive. Aim of this study is to propose an approach to predict elasto-plastic behavior of the hybrid timber column under lateral reversed cyclic loading, assumed to be attacked by big earthquake. The approach adopts a numerical calculation software for reinforced concrete(R/C) members, using Multi-spring model for R/C column yielded at its bottom by moment. The calculation results were verified with experimental results of hybrid columns previous reported in Reference 1, including skeleton curve, hysteresis loop, energy dissipation, and minimization of residual displacement.

The results are summarized as followings:

(i) The RC’s numerical calculation software is extremely useful for us to predict elasto-plastic behavior of the hybrid timber column because the column has no damages expect yielding of joint rebars between its column’ bottom and RC foundation, until 1/50 radian of maximum drifts.

(ii) Skelton curves, reversed cyclic hysteresis loops, and amount of energy dissipation of the columns have been precisely predicted to the experimental results.

(iii) The length of the Multi-spring model for plastic hinge of the column could be recommended to be 7/8 of its column’ depth.

(iv) Equivalent viscous damping factor of the column and final residual displacement in quasi-static free vibration immediately after target displacement, under the column bottom yielding, also were predicted on safe side.