单项选择题
某建筑柱下桩基承台,采用钢筋混凝土预制桩,桩顶标高为-3.640m,桩长16.5m,桩径500mm,桩端进入持力层中砂1.50m。土层参数见图6.4.2所示,地下水位标高为-3.310m,采用半敞口钢管桩,其隔板n=2,外径d=0.5m。试问:确定钢管桩单桩竖向承载力特征值RA(kN)最接近下列()项。()
A.750 B.800 C.850 D.900
A.800 B.900 C.1000 D.1100
A.570 B.675 C.1140 D.1250