Analysis of moisture buffering effect of straw-based board in civil defence shelters by field measurements and numerical simulations

摘要

Moisture problem is one of most serious impediments for the development and sustainable utilisation of civil defence shelters due to poor moisture management. The aim of this study is to develop a passive approach to improve the indoor moisture environment of the shelter, fitting straw-based board on the inner surfaces of walls. The study first conducted long-term field monitoring of room temperature and relative humidity in a typical civil defence shelter in Beijing, and analysed the impact of straw-based board on indoor thermal and moisture environment. The measured results show that straw-based board can dampen the increase in humidity level and improve moisture environment of the shelter significantly, especially in summer. Additionally, a coupling method which combines a well-developed hygrothermal model and dynamic heat transfer in a typical civil defence shelter is used for simulating moisture buffering effect of straw-based board, and the accuracy of the method is validated by the measured data. Finally, using the coupling method, a parametric study is carried out to predict the hygrothermal behaviour of straw-based board for the assessment of its buffering effect in various climate zones of China and for better understanding of its application effect in the civil defence shelter.