Abstract：Liujin Constitution for tou-kungs (bracket sets) of Taihe Palace in the Forbidden City
represented the highest level of tou-kungs in Ming and Qing dynasty. To effectively protect
Chinese ancient buildings, tou-kungs of 1st eave of Taihe Palace were statically tested for their
lateral seismic performance. Based on actual sizes of intermediate set, column set and corner set
of tou-kungs, the corresponding 1/2-scale models (one model for each type of tou-kung) were
fabricated. The tou-kungs were loaded in transverse or longitudinal direction, respectively, and
tested in low-cycle reversed loading conditions. Hysteretic curves of force-lateral displacement
(F-u) as well as the skeleton curves of the models were obtained. Furthermore, the seismic
parameters of tou-kungs, such as ductility, energy dissipation capability, stiffness degradation,
were studied and compared, and a simplified calculation model was proposed for the lateral
stiffness of tou-kungs. Results show that under lateral loads, tou-kungs of 1st eave of Taihe
Palace possess obvious slippage characteristic and poor restoring capability. Stress states of
tou-kungs may vary with the loading direction. With the increase of u, the value of F may firstly
increase, then decrease, and finally tend to be stable. For different types of tou-kungs, the
ultimate bearing capacity Fm may be ordered as Fm (corner set) > Fm (column set, transverse
loading) > Fm(intermediate set, transverse loading) > Fm (intermediate set, longitudinal loading)
> Fm (column set, longitudinal loading); the ductility coefficient μ may be ordered as μ (column
set, longitudinal loading) > μ (intermediate set, longitudinal loading) > μ (column set,
transverse loading) > μ (corner set) > μ (intermediate set, transverse loading); the energy
dissipation capability S may be ordered as S (intermediate set, longitudinal loading) > S (column
set, transverse loading) > S (corner set) > S (intermediate set, transverse loading) > S (column
set, longitudinal loading). Compared to the other 2 types of tou-kungs, degeneration of the
lateral stiffness of column set of tou-kungs may not be obvious. The simplified calculation model
for the lateral stiffness of tou-kungs can be represented by three line segments with the
sequential deceased lateral stiffness.
