Abstract: Blasting replacement method is a soft soil improvement method with high efficiency, low construction cost and satisfactory treatment effect. Its main construction methods can be divided into side explosion and end explosion according to the position of explosives buried. The most effective evaluation of the blasting replacement application is the measurement of the depth of the riprap rock that are brought into the soft soil by the explosion. In order to detect the intertidal zone and depth of the riprap into the soil, in this paper, based on some blasting replacement projects in the Ningde City, the deep horizontal displacement monitoring was performed for a long time. The results of the side and end the horizontal displacement of blasting replacement projects are also compared with the settlement of the above highway embankemnts. It provides reference for similar projects.

Key words: Survey Observation, In-Situ Observation, Blasting Replacement Method, Intertidal Zone