● 基层表面清理不干净，有浮灰、浆膜或其它污物。特别是白灰粘污在基层上，更影响基层于面层的结合；
● the surface of base course is not clean, with floating ash, slurry film or other dirt. In particular, the white ash adhering to the base layer will affect the combination of the base layer and the surface layer;
● 基层过分干燥，抹灰时基层浇水湿润不充分，导致砂浆失水过快，强度不高，与基层粘结不牢。过分干燥的基层表面的粉尘也难于扫除，对面层砂浆起一定的隔离作用；
● the base course is too dry, and the base course is not fully watered during plastering, resulting in the mortar losing water too fast, the strength is not high, and the bonding with the base course is not firm. The dust on the surface of excessively dry base course is also difficult to be removed, and the mortar on the surface layer plays a certain role in isolation;
● 基层过分光，基层有积水，导致水泥砂浆的水灰比增大，影响水泥砂浆的强度和与基层的粘结;为了加强水泥砂浆与基层的粘结力，需涂刷纯水泥浆结合层，操作时如刷浆过早，铺设面层时，所刷的水泥浆已经风干硬结，不但无助于增加粘结力，反而成了一层隔离层。
● the base course is too smooth and there is water in the base course, resulting in the increase of water cement ratio of cement mortar, which affects the strength of cement mortar and the bonding with the base course; in order to strengthen the bonding force between cement mortar and the base course, it is necessary to brush a pure cement mortar bonding layer. During operation, such as too early brushing, when laying the surface course, the cement slurry brushed has dried and hardened, which is not conducive to the increase of bonding force, but becomes a layer of separation Abscission layer.