Abstract:A series tests had been conducted to study the safety performance of a new type plug-in steel-tube scaffold system

including tests of connecting reliability of plug in

semi-rigid behavior of joint

basic unit mechanic behavior and four pieces of full-scale outdoor scaffold. The results indicate that the plug-in is stable and can not slide upward under usual work state

the joint is safe and should not fracture prior to steel tube. The joint rigidity can affects load-carrying capacity evidently and it is unsafe if a large connecting rigidity is adopted in calculation.A suggested joint rigidity was given. It will be safe and has a large load-carrying capacity if the suggested semi-rigid model and safety factor are used in calculation.