ASSESSMENT OF THE EFFECT OF THE STRUCTURAL SOLUTION OF A PRECAST-MONOLITHIC FRAME ON ITS LOAD-BEARING CAPACITY AND DEFORMABILITY USING A FULL FACTORIAL EXPERIMENTAL DESIGN
- Authors
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Khamrokulov Ulugbek Damirovich
Mirzo Ulugbek Samarkand State Technical University, Samarkand, Uzbekistan
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- Keywords:
- design of experiments full factorial experiment regression equation Student’s t-test precast-monolithic frame permanent formwork floor-slab type failure load deflection
- Abstract
- The paper presents the procedure and results of processing the tests of precast-monolithic frame building models by the method of mathematical design of experiments. Two qualitative factors that define the structural solution – the type of frame elements (conventional monolithic elements, or a composite column in permanent shell formwork with a U-shaped precast-monolithic beam) and the type of floor slab (monolithic or precast hollow-core) – were included in a two-level full factorial (22) design. Tests of three 1:4 scale models formed three points of the design. Linear regression equations were derived for the first cracking load, the load at the limit deflection, the failure load and the deflection, and the significance of the coefficients was checked by Student’s t-test (p = 0.05). For all four responses the coefficient of the frame-element type was found to be insignificant, and the only significant factor was the floor-slab type: the transition to a precast hollow-core slab reduces the failure load by 10.86 kN and increases the deflection by 2.39 mm. The indicators of the untested fourth variant were predicted by the additive model. The results provide a statistical basis for using the composite column in permanent formwork and the U-shaped beam instead of conventional monolithic elements.
- References
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