Experimental apparatus and method for hyporheic zone under field riverbed evolution

The invention relates to an experimental apparatus for a hyporheic zone under field riverbed evolution, comprising a foundation pit excavated at the bottom of a riverbed; water-filtering geotextile is spread at the bottom of the foundation pit, a rectangular container formed by splicing and enclosing a plurality of combined plastic plates is arranged above the geotextile, and the bottom of the rectangular container is fixed to the riverbed; the combined plastic plates are each composed of a plurality of plastic plates with round holes, a sampling hole is provided between upper and lower plastic plates, the outside of each sampling hole is covered with veneer, and the inside of each sampling hole is covered with thin film; grit accumulated in wavy form is contained in the rectangular container, a plastic mesh is spread above the grit, the plastic mesh is lapped to the combined plastic plates through lap fasteners. By setting up a river slope and physiochemically analyzing water coverage on the sand slope and by using the experimental apparatus to perform layered sectional sampling on the inside of the sand slope, riverbed evolution in the hyporheic zone riverbed is obtained; by using the reasonably designed experimental apparatus, it is easy to perform field experiments under complex geographic conditions.