严寒地区围护结构的防潮验算
Moisture proof calculation of envelope in severe cold zone
摘要：
建筑材料的透水性对墙体热工性能乃至结构安全有重要影响。采用工程上广泛应用的露点法对严寒地区部分城市的围护结构进行了防潮验算。计算结果表明：严寒地区保温材料布置在主体结构外侧有助于降低水蒸气在围护结构内部凝结的风险；既有建筑中广泛使用的黏土砖具有良好的透水性；新建建筑中增加砌块厚度对防止水蒸气凝结的作用有限，增加保温材料厚度有助于防止围护结构内部发生水蒸气凝结；提高室内干球温度或相对湿度都将增加水蒸气凝结的风险，且室内温度愈高相对湿度的影响愈明显。根据计算结果，提出了一个量纲一物理量——凝结因数，简化了传统的验算方法。
Abstract：
The permeability of building materials significantly influences the thermal performance and structural safety of walls. Checks the envelope moisture proof performance in some cities of severe cold zone in China by dew point method widely used in engineering projects. The results show that in severe cold zone of China, the thermal insulation materials installed on the outside of the main structure is helpful to reduce the risk of water vapor condensation inside the structure. Clay bricks widely used in the existing buildings have good permeability. In the new buildings, increasing the thickness of the concrete block structure rarely contributes to protect the walls from the water vapor condensation. Increasing the thickness of the thermal insulation materials helps to reduce the risk of condensation. The rise in indoor dry bulb temperature or relative humidity will increase the risk of condensation, and the higher the indoor temperature, the more obvious the effect of the relative humidity. Proposes a dimensionless physical parameter—condensation factor, which simplifies the traditional calculation, according to the calculation results.
Keywords:envelope, moisture proof calculation, water vapor, condensation, severe cold zone, permeability