Experimental Study On The Mechanical Properties For The Template Bracket Under The Flange Of Box Girder

Bowl buckle falsework because of good mechanical performance, highefficiency of construction, easy management, better economy and so on, has beenwidely used in the various bridges and a series of high-rise building construction. Theformwork of cast-in-place reinforced concrete box girder has the features of greatheight, big span, high load weight, which bring great difficulty to the design offormwork support frame. In the concrete pouring process, the edge position of wingproduces horizontal thrust, that results in formwork and frame deformation, and evenproduces engineering quality accident. As scaffold material defect, improper designor construction, serious accidents with heavy casualties have occurred nationally,causing heavy economic losses and serious social impact. Therefore, it has animportant theoretical and practical significance to make theoretical and experimentalresearch on the mechanical performance of the bowl buckle falsework.The thesis, based on falsework in the West-Sanhuan-Navigation-Roadinterchange project in Zhengzhou City, employed theory and practice combinationmethod to explore the behavior of bowl buckle falsework during the concrete pouring.Main conclusions as follows:（1）Diagonal brace and cross bracing is sensitive to the asymmetric pouring, inthe whole process of concrete pouring, construction should be performed strictly inaccordance with the design of casting and casting speed. When pouring concrete boxgirder, using back-shaped pouring sequence can make the support force is moreuniform, which is conducive to ensure the safety of the frame body.（2）By effect of uneven pressure and three to the scissors, the axial pressure onvertical rod of the upper may be larger than that of the lower, show that three to thescissors and the bracing has a very important role in the formwork supportperformance, can rise to "the redistribution of internal force" rol. The vertical rodnode must be set to "uplift tectonic" in support design. （3）Test shows that the influence range of concrete pouring is within the testsection before and after12m.（4）Diagonal brace to play the role is not only related to the number of fasteners,but also the position of diagonal brace and fastener.“45°diagonal” under the flange ismainly in tension in the upper part and mainly in compression in the lower part.Scissors is mainly in tension overall.