THE ANALYSIS AND DISPOSITION OF A COLLAPSE OF THE HIGH SCAFFOLDING FOR BRACING FORMS

Based on the collapse of the high scaffolding for bracing forms,the cause of collapse was analyzed;it was that the constructional requirements of standard were not met.The importance of vertical cross bridging of the scaffolding was analyzed by the rigid-connected and the hinged models respectively.It was found that variable geometry system had become the invariable one for the hinged model when the cross bridging was added to the scaffolding;on the other hand for the rigid-connected model,the axle force of the vertical bar was reduced by more than 25% compared with that of the one without the cross bridging.The removing scheme was discussed.The secure line was set up before the removal work began; for the collapsed in zone Ⅰ part,the concrete plate was removed firstly.At the same time the main beam and the mesh reinforcement were remained to keep the force balance.The steel wire netting was set up on the surface of the deforming scaffolding in zone VII to strengthen the scaffolding.At last,the removal sequence of the whole structure was determined and the collapsed part was removed smoothly.