Abstract：A covered-type of sheet-piled structure has recently been proposed to overcome the problem that the conventional sheet-piled structure is only applicable in medium and small wharfs，which has long been the difficult problem of port engineering. Incorporating with the construction need of a deep water berth of 100 000 DWT，a study for the proposed covered sheet-piled structure is conducted by means of centrifuge model test to investigate the distribution of bending moment of the front sheet-piled wall，covered sheet-piled and anchor wall，and the horizontal displacement on the top of the wall and the tension force of connecting rod. To illustrate the contribution of barrier piles to the wharf performance，the conventional structure without barrier piles under no surface work load as well as the proposed new structures are modeled，in which the surface load，ratio of embedment of front wall，and distance between front wall and barrier pile are considered as influential factors. Test results show that the maximum bending moment of the front sheet-piled wall is obviously decreased，with smaller magnitude of seawall horizontal displacement and tensile force of connecting rod. Thus the problem perplexing engineers is promisingly overcome by application of this new structure of sheet-piled wall. Three modes of connection are conducted in the model test to find out the best connection mode between the front sheet-piled wall and the barrier piles，such as rigid connection through breast wall，rigid breast wall connect with vertical freedom，and hinge jointing connection through short connecting rod，respectively. It is found that the third one，i. e. the hinge jointing connection through short connecting rod，is preferable to the others in decreasing bending moment of these structure elements. Based on the analysis of the test results，an optimum scheme is recommended for the project to be built.
