Effect of intensified freezing process on deformation control of ice wall

Deformation of ice wall is the main factor that must be carefully controlled in sinking of frozen shaft. With the increase of thickness of Quaternary alluvium, through which the shaft pass, it becomes more and more important to control the deformation of ice walk especially in deep thick clay layer. In fact, the deformation of ice wall in deep thick clay layer has greatly taken place while the shaft bottom closed. Therefore, a special freezing method(we called it intensified freezing process) has been used, which is different from that used in sand and rock strata conditions. This paper summarizes the key points of intensified freezing process used in frozen shaft sinking through deep thick clay layer. With that process the deformation of ice wall before exposure (we named it deformation of lead)is effectively controlled . With FEM. calculation and case study, it is proved that the maximum amount of deformation of lead is up to 63.15% of total deformation and intensified freezing process can decreased deformation of lead greatly. It means that intensified freezing method for is an effective freezing method for reducing deformation of ice wall.