Prestressed scaffolding system

Abstract

An innovative prestressed scaffolding system is provided to use triangular tendon supports and tendons in place of a plurality of struts for supporting the earth pressure applied during an excavation or an underground construction structure, thereby removing the obstacles of the construction, e.g., intermediate piles or struts, and contributing to an improvement of the constructional efficiency of the underground space and reduction of construction costs.

1 . A scaffolding system for supporting the excavated earth retaining wall by forming a polygonal closed section, comprising: 
 a prestressed wale comprising a plurality of triangular tendon supports in the middle portion, a tendon-anchoring unit at both ends of said wale, and a connecting brace for connecting said supports and said tendon-anchoring unit; and    a strut constituted by a truss or a plurality of H-beams or an H-beam having a large cross section and strengthened for supporting said tendon-anchoring unit.    
   
   
       2 . The system as defined in  claim 1 , wherein said triangular tendon support is constituted by a vertical member and inclined member, or only by vertical members, or only by inclined members for forming a triangle and supporting said wale.  
   
   
       3 . The system as defined in  claim 1 , wherein said angular tendon support is supported and connected by an intermediate pile and a support beam for the tendon support.  
   
   
       4 . The system as defined in  claim 1 , wherein said tendon-anchoring unit fixes a tendon and couples with said wale for applying the compression force and fitter couples with said inclined member or vertical member for supporting the generated force.  
   
   
       5 . The system as defined in  claim 4 , wherein said tendon-anchoring unit forms an isosceles triangle by using frame materials, the corner of said isosceles triangle is reinforced by a reinforcing member, wherein said tendon is fixed at one corner of said isosceles triangle and a member facing said corner is directly connected to a truss strut or through a hydraulic jack or a screw jack, and the portion connected with said wale has a length adjusting function.  
   
   
       6 . The system as defined in  claim 4 , wherein said tendon-anchoring unit forms a trapezoid by using frame materials, the corner of said trapezoid is reinforced by a reinforcing member, said tendon is fixed at both corners, and the middle portion is directly connected to said truss strut or through a hydraulic jack or a screw jack.  
   
   
       7 . The system as defined in  claim 4 , wherein said tendon-anchoring unit may be provided with an inclined or vertical strut, a tendon entered from one side of said tendon-anchoring unit is fastened at an opposite side, a single wale or a double wale may be supported by said tendon-anchoring unit, and said tendon-anchoring unit is equipped with a screw jack or a precedent load jack having a length adjusting function.  
   
   
       8 . A scaffolding system forming a polygonal closed section only by using a prestressed wale comprising a plurality of triangular tendon supports in the middle portion, a tendon-anchoring unit at both ends of said wale, and a connecting brace for connecting said supports and said tendon-anchoring unit.  
   
   
       9 . The system as defined in  claim 8 , wherein said tendon-anchoring unit is a corner anchoring unit and is designed to be connected with said wale and to fix a tendon at both sides.  
   
   
       10 . A vertical prestressed scaffolding system for supporting a channel type excavating surfaces wherein a slab of the structure and intermediate struts are used as supports, an H-beam is inserted from behind a built wale, a short support is attached to the front of said wale and supported by a tendon, wherein said tendon is fastened to an anchoring unit of both ends of said wale.  
   
   
       11 . The system as defined in  claim 10 , wherein said tendon-anchoring unit is for a vertical prestressed scaffolding system in which said wale or vertical beam is removably manufactured.