| 摘要 |
FIELD: construction industry, highway engineering, construction of bridges and scaffold bridges of transportation complexes in cities under conditions of cluster housing. SUBSTANCE: process of erection of bridge or scaffold bridge includes erection of bearings and of at least one framework uncut in length of reinforced concrete longitudinal beams laid sideways and forming one branch as minimum. Beams are made on jig produced from monolithic or prefabricated reinforced concrete by casting concrete in dismountable forms by sections with reinforcement of relaxed and stressed fittings with subsequent longitudinal-cyclic thrust of sections with the aid of end platform till each section is placed in design position. In this case stressed fitting are put in closed conduits in the form of bundles formed from wire strands, and/or bars, and/or belts made of high-strength material including metal and/or metal-based laminate, or high- strength carbon-carrying or polymer filaments. Some conduits are rectilinear and some conduits are curvilinear or polygonal in which vertical section convexities and concavities corresponding or proportional to epure of bending moments are arranged. Working fittings located in rectilinear conduits are stressed within limits of each section before its thrust and movement from jig, fittings located in curvilinear or polygonal conduits are pushed or drawn after thrust of entire framework or of its moved branch and are stressed after thrust of all sections forming framework or its moved part or branch. Relation of cross-section areas and/or bearing capacities of fittings stressed by sections and of fittings stressed after thrust to design position of entire moved part or branch of framework is assumed to be (0.5...0.95):(0.5...0.05). EFFECT: reduced usage of materials, labor input and energy consumption in process of erection, diminished erection time with simultaneous provision for safety of erection operation and reliability of erected structure. 20 cl |
