Study on quality inspection and evaluation for old embankments of Huayang River Flood Storage and Detention Area

In order to master the filling quality of the old embankment in the Huayang River Flood Storage and Detention Area Construction Project (Anqing City), a point line combined quality inspection method using surface wave method for general survey and portable dynamic penetration for detailed survey was proposed. Taking the Fuhua section embankment as the research object, on-site experiments were carried out to obtain the relationship curve between the surface wave velocity and cone tip resistance of the old embankment body with depth changes. The corresponding compaction evaluation criteria were proposed, and the filling quality of the old embankment was assessed through numerical seepage analysis, and corresponding treatment measures were proposed. The results showed that the surface wave velocity presented an overall increasing trend with the increase of compaction degree, and the average cone tip resistance was significantly positively correlated with the compaction degree of the old embankment. The survey used a surface wave velocity of 172 m/s corresponding to 93% compaction as the standard. For detailed investigations, the cone tip resistance values corresponding to 88%, 90%, and 93% compaction levels were adopted as standards, revealing a distribution characteristic of the old embankment body where compaction was higher at the top and bottom, but lower in the middle along the depth direction. When the compaction degree of the old embankment is low, there is a problem of seepage stability in the embankment body, which can be treated by measures such as cut-off walls.The research results can provide a reference for similar embankment projects.