General characteristics
==========================


Geometry
---------

It is a beam that is simply supported on its two supports [:ref:`Figure 1.1-a <Figure 1.1-a>`].


.. image:: images/1007EACC000031320000313263846BFE75B4E5C2.svg
    :width: 285
    :height: 285


.. _RefImage_1007EACC000031320000313263846BFE75B4E5C2.svg:

**Figure 1.1-a: structure geometry**


Material properties
-----------------------


* Concrete: :math:`E=37272\mathrm{MPa}`, :math:`\nu =0.2`, :math:`\rho =2400\mathrm{kg}/{m}^{3}`


* steel: :math:`E=200000\mathrm{MPa}`, :math:`\nu =0.33`, :math:`\rho =7800\mathrm{kg}/{m}^{3}`


* damping: Rayleigh type (:math:`\alpha K+\beta M`), with 5% on modes 1 and 2


Boundary conditions and loads
-------------------------------------

Simple press in :math:`B`: :math:`\mathrm{dy}=0`

Press "double" in :math:`A`: :math:`\mathrm{dx}=\mathrm{dy}=0`

To avoid out-of-plane modes, the following degrees of freedom are blocked all over the beam: :math:`\mathrm{rx}=\mathrm{ry}=\mathrm{dz}=0`

Loading: earthquake *ac_s2_c_1* [:ref:`Figure 1.3-a <Figure 1.3-a>`], in the :math:`\mathrm{OY}` axis applied to both supports (signal amplification factor = 137).

**NB:** transverse reinforcements are not taken into account in the calculations


.. image:: images/1001458C000032DA00001E6310CCD41E14FA24CF.svg
    :width: 285
    :height: 285


.. _RefImage_1001458C000032DA00001E6310CCD41E14FA24CF.svg:

**Figure 1.3-a: Accelerogram ac_s2_c_1** **imposed on the structure**