Abstract: Physical parmeters were selected according to the experiment.Effects of rigidity of mega frame structure and raft foundation influence on sandy pebble soil foundation settlement and stress distribution in construction process were analyzed.The results demonstrated that superstructure rigidity influences foundational settlement and reaction force of subgrade foundation more significantly than layer of structure finite.As raft plate rigidity increases,foundational settlement and differential settlement decrease.Reaction force of subgrade foundation concentrates towards the edge,resulting in distribution ununiformity and normal stress increase.