There is the torque on the wall, which tends to rotate it.
As it rotates, the diagonal forces down, the ground resists and compression is created.
The other side of the wall, raises forces which oppose the beams which lower static loads and so tension is created. If there were no beams to stop the upward force of the wall strut, there would be rotation and overturning of the wall.
If there was no rotation of the wall there would be neither upward force nor the reaction of the beams nor tension on the wall face. In principle without pre-stressing only by butting the edges of the wall from the roof with the ground stops 1. the rotation - overturning of the wall. 2. it stops the upward force because it received it from the roof ( and not from the base ) and sent it into the ground. If the footing was between the base and the ground there would be tension in the wall.
But there is no tension because the footing is between the roof and the ground.
3. There is no tension when upward force is received, from the roof, and through the free passage tendon is deflected into the earth.
Lymperis, I.N.
(2023) The Ultimate Anti-Seismic Design
Method.
Open Journal of Civil Engineer-
ing, 13, 771-801.
https://doi.org/10.4236/ojce.2023.134051
Dear Dr. Samy Elhadi Oussadou
There are two issues in the response of structures to seismic displacements.
1. The balance of compensatory forces
2. The strength of the cross-sections to take up the equilibrium compensating forces.
My research focuses on 1. Increasing the compensating forces without increasing the mass of the structure which increases the seismic loads. This is possible when we introduce to the structure additional external forces coming from the foundation soil which are strong, have no mass, and additively increase the response of the structure to seismic intensities.
2. I am trying to increase the strength of the materials and sections without increasing their mass which increases the seismic loads. To achieve this I do two things.
α. I use controlled post-tensioning to increase the active cross section of the walls, neutralize stresses and increase the capacity of the sections in shear and towards the base shear and generally increase the bearing capacity by reducing the inelastic displacements.
β. My design is such that the structural materials of concrete and steel receive only those forces to which they have super strengths.
We know that concrete has super resistance to distress.
We know that concrete cannot withstand tensile and shear stresses
To me it is prohibitive to stress concrete with shear stresses developed at the interface of concrete and steel, because the concrete will fail prematurely before the steel has exhausted its super tensile capabilities. To stress concrete only by compression and not by shear, we need to eliminate the mechanism of concrete-steel cooperation, that of confinement, and replace it with that of prestressing which includes a free-pass tendon.
Dear my friend: Ioannis Lymperis ,
My dear friend, I am not familiar with this:
I think the correct placement of the elements used by you, which takes into account the microstructural structure of the area.
using a flexible synthetic material that meets your expectations combined with the methods you use.
Regards.
Laszlo
Dear Samy Elhadi Oussadou
Yes, you got it right.
By prestressing I am increasing stiffness, creating active strong cross sections to all stresses without increasing mass and seismic loads. But I do increase the wall moment with stiffness. To prevent the large moment from transferring to the beams and the connecting beam of the base and breaking them, I deflect it into the ground.
On the other hand today it is impossible to control the inelastic displacement. What I'm doing is using the force of the ground and post-tensioning, to stop the inelastic deformation
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