Abstract：Due to the difference of depth of breast wall in the construction techniques of Zhang¢s and Bai¢s split grouting，the position of original split dam body is different in these two techniques，which will influence curtain shape of dam body，origination point of split grouting，the movement law of grouting fluid and mechanism of grouting. The curtain shapes of Bai¢s split grouting are divided into three types，longitudinal，transverse or oblique and horizontal orientation，and Zhang¢s five types，cross orientation and semi-pile coagulate plate besides the above three types. The difference of these curtain shapes is prominent in the two techniques. For example，Bai¢s longitudinal curtain shape is big in middle and small at two ends，and Zhang¢s is wide at underside and narrow at upside. Bai¢s origination point of split grouting is stochastic，and Zhang¢s is artificially controlled. The generalized physical model of Bai¢s grouting fluid movement is dot-line-side，and Zhang¢s is dot-side. Research on Bai¢s theory and mechanism of grouting are more mature and there are operation codes based on it，but there are no practice by it out off the range stated in operation codes. Zhang¢s continued to use Bai¢s theory，mechanism and criterion of grouting. But whether it is appropriate is to be studied. It is a pressing task to resolve problems of thinner curtain or no curtain at bottom of dam body in Bai¢s and establish the framework of Zhang¢s theory. Accordingly，advices on emendation of the active code are given in this paper.
