Mechanical State Model of Multispan Continuous Deep Beam under Concentrated Load

In the present study, the mechanical model of the multispan continuous deep beam under concentrated load was established on the state space theory, and with the model, the two-span continuous deep beam was calculated. And the calculation results are consistent with ANSYS results, which show that the model without the plane section assumption is accurate and applicable. The changes of the deflection and the section strain along the beam height were analyzed with the beam height variation. The results showed that the normal stress and the shear stress coexisted in the cross-section of multi-span continuous deep beam, which means that the shear stress can cause the cross section warping, while the normal stress can result in the section in parallel with the neutral layer extrusion. In addition, we incidentally found that, with the increase of the beam height, the impact of the buckling deformation and the extrusion deformation impact on the beam bending increase gradually. A new design method, which has been provided by the established mechanical model of the multi-span continuous deep beam, has extended the space of the calculation method on traditional continuous deep beam.