Water-sediment compound simulation test device for accurately layering and collecting sediment

The invention relates to a water-sediment compound simulation test device which is formed by combining a testing column with a built-in layering testing cylinder, wherein an outer cylinder top cover is transparent and detachable; a sampling valve is arranged on a side face; the water replenishing and water sampling operations can be carried out conveniently; and a dewatering valve is arranged on the bottom of the side face. If the device is used for a test, an inner cylinder is taken out firstly, and then the inner cylinder is slowly descended to the outer cylinder by taking a cotton thread by hand after being filled with the acquired field sediment, an evacuation valve is closed, water is slowly filled in from the top of the outer cylinder, and then the test is started. When the sedimentsample is needed to be taken, the following operations are performed: exhausting the water of the outer cylinder by using the evacuation valve of the outer cylinder and then taking out the inner cylinder by taking the cotton thread by hand; taking off a PVC (polyvinyl chloride) short plug from one bottom corner of the inner cylinder and pulling out a PVC long nail from an inner cylinder top corner corresponding to the bottom corner by firmly holding a nail cap; inserting gaskets in layers by starting from the top layer and rotating the inner cylinder and gaskets by using the PVC long nail at another corner as a shaft; and then vertically moving the gaskets downwards, thereby guiding the sediment on the layers to fall onto the gaskets. Different layered sediment samples can be convenientlyand accurately acquired by performing the operations layer by layer.