Creep of Sugi (Cryptomeria japonica D.Don) structural members processed by various drying methods

In order to gather information about the influence of drying methods on Ion term performance, a bending creep test (B-test) and a compression creep test perpendicular to the grain (C-test) were conducted in practical conditions for the conventional construction in Japan. The specimens used were sugi (Cryptomeria japonica D.Don) structural members in green conditions for B-test and air-dried conditions made by various drying methods for both B-test and C-test. For the B-test, the creep test was applied at 4 points with the stress levels of standard allowable unit stress by 1.1. And for the C-test, column-and-sill joints for the conventional construction in Japan with two different tenon lengths of 90mm (S-type) and 105mm (L-type) were manufactured, then the compression creep test perpendicular to the grain was examined with the loading condition of 891kgf, which is the maximum column axial designed load for a model house. As a result, the difference of creep behavior was hardly recognized among the drying methods for both B-test and C-test, whereas the creep deflection of green specimens was much higher than that of air-dried specimens for the B-test. For the C-test, the creep displacement of S-type was much higher than that of L-type.