HG70板盒型承载结构件结构复杂，加强筋多，焊缝交错，焊接过程中变形大，位置尺寸要求严格，各连接孔较深，加工难度大。由于HG70板材料的特殊......

Based on field geological survey, interpretation of seismic reflection profile and thermochronology dating, this paper s......