(1) Protective layer laid around the building to prevent rainwater from infiltrating.
2 commonly known as "three-point water". Calligraphy terminology. The writing method varies with the font and style of the book. Zhang Huaiguan's "Forbidden Classics, Different Laws, Tang Wang Sanshui" in the Tang Dynasty said: "The names of Tanya are different. Whether the intention is hidden or revealed is different in form; The method is constrained in the middle by the rigid side, and the dive is frustrated. Then "Huang Tingjing" and "Le Yilun" of the right army also used this. The name' English' looks at each other. Although it is detached from the outside, it is attached to the inside. This method is called clock (response). Up and down the' *', we use the latent front to hide the secret, and the next one is sent out quickly, followed by the right army, which is what Zhen Li often does. Ju's running script. Micro-pressure reveals the law, which means that light benefits are beautiful. Zhong (Yi) and Zhang (Zhi) wrote books by this method. "
(3) aproll is the vertical connection between the outdoor ground and the external wall, which is used to remove rainwater and protect the wall foundation from rain erosion. The aproll width should be determined according to soil properties, climatic conditions, building height and roof drainage form, which is generally 600 mm ~1000 mm. When the roof adopts unorganized drainage, the aproll width should be 200 mm ~ 300 mm longer than the cornice. In order to ensure smooth drainage, the apron slope is about 3% ~ 5%, and the apron outer edge is 30 mm ~ 50 mm higher than the outdoor terrace. The commonly used materials of aproll are concrete, cement mortar, pebbles and stones.
In addition, open ditch drainage can be used in areas with large annual rainfall. Open ditch is a drainage facility that introduces rainwater into urban underground drainage pipe network. Generally, in areas with annual rainfall above 900mm, open ditches are used to drain rainwater around buildings. The width of open trench is generally about 200mm, and the material is concrete, brick, etc.
In the building, in order to prevent aproll or cracks at the joint between open ditch and plinth after building settlement, joints should be set at this part, and flexible connections should be made with elastic materials.