Research On Mechanical Performance And Experiment Of Cast-in-situ Concrete Hollow Slab Column Structure Subjected To Horizontal Load

The cast-in-situ hollow conerete floor system is one of the new systems that occurred in China. This kind of structure system has many advantages such as stinting material, larger span, lightening deadweight, better effects on insulation of thermal and sound, and it can lower the synthetic cost. Now, it has been listed in Major Promotional Projects by Ministry of Construction of P. R. China. Though "Technical specification for cast-in-situ hollow conerete floor structure" was published in 2004, as a new technics, its mechanical performance have not been comprehended adequately. Its calculating theory and design measures are still not consummate. In this paper, the mechanical performance of the structure, the calculating width of euqivalent beam and its affecting factors are studied by theoretical analyses and experimental researches.The main contents can be divided into five parts.1,The research background and present research condition at home and abroad are reviewed and summarized. And the equivalent frame method adopted in PKPM series software design is introduced in detail.2,The bidiretional bending stiffness of the cast-in-situ concrete hollow floor laying tube filler unilaterally is analyzed based on the conception of " average stiffness" . Through the establishment of an analysis model for the calculating width of euqivalent beam, the calculating formula on equivalent width coefficient for the equivalent frame beam of cast-in-situ concrete hollow slab-column structure is proposed.3,Using the finite element software ANSYS, this paper analyzes the influences of the collocation direction of the tube on the model of the equivalent frame, and the relation between the equivalent width coefficient and the main geometric parameters. It is pointed out that the equivalent width coefficient of the cast-in-situ concrete hollow-slab column structure is wider than that of slab column structure with the same geometric parameters.4,Tests on the 1/3-scale cast-in-situ concrete hollow slab-column structure subjected to horizontal loads are performed. The mechanical behaviors of the hollow slab-column structure under the horizontal loads are studied by experimental researches. The load-displacement hysteretic curve and skeleton curve of the structure are obtained. The ductility of the hollow slab-column structure is also analyzed. The shear lag phenomenon has been confirmed by analysis of strain curves for the concrete and reinforcement; The formula for the calculating width of the equivalent beam in elastic stage is verified by comparison of equivalent frame beam width coefficients among theoretical value,experimental value and GB50010-2002 code value. It is also proposed that the code value prone to safe.5,The future development of this field is predicted based on the summaries of the main contents of this paper.