In recent years， cases of using shield machines to cut concrete foundations during urban tunnel construction have been increasing steadily. It is of great significance to investigate the forces and wear of the shield scrapers for the safety and efficiency of shield tunneling and the expansion of the shield machine application. Based on the previous tests， numerical simulations of using scrappers to cut concrete are performed by using the software EDEM. And the effects of the cutter parameters （the tool rake angle， tool relief angle， and tool-tip shape）， the sample strength， the cut depth， and the cutting speed on the forces acting on the scrapers are investigated. And wear of cutters is also discussed based on the Archard model. Calculation results show： 1） The force on the cutters decreases with the increase of the tool rake angles. 2） The tool relief angles and the tool-tip shapes have a small influence on the forces on the cutters. 3） The force on the cutters increases with the concrete sample strength， the cut depth， and the cutting speed. The averaged calculations of the forces have good agreement with the results obtained from the tests on the whole. The most worn part is the cutter tip； more serious cutter wear is observed when subjected to a larger tool rake angle； the cutter wear amount increases with the increase of the concrete sample strength， the cut depth， and the cutting speed. The findings can provide good references for shield scrapper design.