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中国板桩码头结构的设计和建设从2000年前的3.5万吨级到现今的20万吨级,有了长足的进步.新提出的一种20万吨级卸荷式板桩码头结构,考虑了刚性较大的T型地连墙方案和柔性较大的组合钢管桩前墙方案,与之相对应的卸荷承台群桩基础结构中分别设置2排和3排直立灌注桩.开展了大型土工离心模型试验,对这两种方案的卸荷式板桩码头结构性能进行了验证.结果发现,这两种方案都是可行的,前墙位移均在允许范围内,其中刚性较大的 T 型地连墙方案中,前墙锚着点位移较小,但墙身弯矩反应较大,拉杆力较小,承台群桩基础结构中灌注桩弯矩反应正常,而柔性较大的组合钢管桩方案中,前墙锚着点位移较大,但墙身弯矩反应较小,拉杆力较大,承台群桩结构中灌注桩弯矩反应较强.前墙和灌注桩弯矩反应强烈程度所呈现的此消彼长特性,揭示了卸荷式板桩码头中单锚式板桩结构部分和卸荷承台群桩基础结构部分之间的荷载分担工作机制.“,”There is a great stride in the design and building of sheet-pile wharfs in China from 35000-tonnage before the year of 2000 to 200000-tonnage at present. Two design schemes are proposed to verify a 200000-tonnage sheet-pile wharf with relief platform. One has the rigid front wall of the reinforced concrete diaphragm of T-shaped cross-section with relief platform of 2 rows of vertical cast-in-place piles. The other has flexible front wall of composite steel pipe pile with relief platform of 3 rows of vertical cast-in-place piles. Two series of geotechnical centrifuge tests are carried out to investigate the performance of the sheet-pile wharf. It is shown that the two design schemes are verified to be feasible in that the front wall displacement is within the allowable limit. The response of the wall bending moment of the front is greater for the former scheme than for the latter scheme, whereas the displacements of the front wall at anchorage, the internal forces of tie-rods and the maximum bending moments of cast-in-place piles are smaller for the former scheme than for the latter scheme. The load transfer mechanism between the internal sheet-pile structure with a single anchorage and the pile group with relief platform is fully revealed from the above-stated shift of bending moment response intensity between the front wall and the cast-in-place piles.