Authors:
Kongyang Chen
1
;
Menglin Sun
2
and
Hongxing Qiu
1
Affiliations:
1
Key laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, School of Civil Engineering, Southeast University, Nanjing and China, China
;
2
Architecture Design Institute, China Railway Liuyuan Group Co. Ltd., Tianjin and China, China
Keyword(s):
Timber members, Moisture transfer, Diffusion coefficient, Surface emission coefficient, Finite element method.
Abstract:
Anhui fir is a common building material in southeast China. As the basement of the research for shrinkage cracks and durability of timber structures in natural environment, this paper investigates the moisture content distribution and moisture transfer process in transverse cross-section of timber members made of Anhui fir. Now, the mostly used equations for calculating diffusion coefficient and surface emission are based on Norway spruce, which is actually not suitable for Anhui fir due to their different kinds of trees. Firstly, based on Fick’s second law, the diffusion parameters and boundary conditions in humidity field and temperature field were analogized. Then, experiment in constant temperature and relative humidity was done. Experimental result showed the polynomial moisture content distribution in transverse direction, and exponential change with time, which was used for deriving new formulas for calculating diffusion coefficient and surface emission coefficient of Anhui fi
r. Finally, the Abaqus heat transfer analysis was used to simulate the moisture transfer process by substituting corresponding parameters successfully, and the results agreed well with experiment.
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