石膏制品耐水性差,通常只能用于相对湿度在60～70%以下的房间。为了扩大石膏制品的应用范围,首先要解决耐水性问题。因为石膏在20℃时具有0.2%的溶解度,如长期遭受雨淋,就会因石膏的溶解而使制品变形。石膏制品透水性大,易吸水,吸水后的强度仅为干燥强度的一半。由于上述原因,石膏制品的应用范围以及使用量都受到限制。我翻阅了大量资料,并作了很多试验,终于获得成功。我厂试产了三批共1万平方米,专门用于地下工程的防水石膏吸音板。根据对 Gypsum products have poor water resistance and can only be used in rooms with a relative humidity of 60 to 70%. In order to expand the scope of application of gypsum products, we must first solve the problem of water resistance. Because gypsum has a solubility of 0.2% at 20°C, such as being exposed to rain for a long time, the product will be deformed due to the dissolution of gypsum. Gypsum products have high water permeability and are easy to absorb water. The strength after water absorption is only half of the dry strength. For the above reasons, the scope of application and the amount of use of gypsum products are limited. I read a lot of information and made a lot of experiments and finally succeeded. Our factory has trial-produced three batches of 10,000 square meters, which are specially used for underground engineering waterproof gypsum sound-absorbing panels. According to