How can we prevent earthquake?in this question i am asking ways to prevent earthquake and damage caused by it.

Earthquake protection of buildings by a double concrete slab foundation.

by Charles Weber, MS

retired

1908 Country Club Road, Hendersonville, NC 28739

 

Abstract

Protection of buildings by double slab construction with lubricant in between and centered by springs.

Keywords: slab; concrete; earthquake; spring; oil; construction; base isolation

*Corresponding author. isoptera@att.net

Introduction

I have a suggestion that is applicable to earthquake damage control. Buildings are very strong in vertical compression. I believe it is side to side motion that is ruinous. So if a thick reinforced slab were first poured and covered with grease or oil before the actual building concrete basement floor were poured, I suspect it would eliminate side to side motion during an earthquake. Of course it would be necessary to have some kind of spring or air piston on the sides to prevent wind motion.

Construction as described in patents US6289640 B1 and US4599834 A work on the same principle of sliding surfaces as my invention but are elaborate and expensive to construct. JP2003301625 A is only for small light buildings.

Discussion

A building protected as above would have no covalent or valence bond links to the ground and no support from earth on the sides to support the building. So very tall buildings would seem to be vulnerable to toppling. However, in addition to the weight of the building and the weight of the upper slab, the atmosphere is pressing down with a pressure about one ton per square foot because the interface is effectively sealed. Thus there is no chance at all that a three story building would topple nor even a six story building. If the slabs were extended out to the sides and the upper one suitably thick and reinforced and buttressed, much greater than six story buildings should be safe as well. Even much higher buildings yet should be safe if the side retaining springs are attached high up.

Making the upper slab thick would give the structure desirable added inertia. This would be inexpensive to achieve because the upper slab would not have to be smooth on top. Therefore, boulders could be incorporated into it.

The primary consideration would be to use an oil with a very low viscosity, since viscosity of the oil is undoubtedly the primary resistance to the top slab trying to follow the bottom slab. A silicone oil is probably the oil of choice for most buildings because of its resistance to change from temperature. Silicone coated river sand might work well also for low buildings.

An advantage of this procedure is that it would require less skilled workers and less maintenance than other methods. One big advantage of this procedure is that it should be fairly easy to retrofit existing buildings, because it should be possible to underpin a few hundred square feet at a time. When building new, making the bottom slab a little concave upward would probably make less stiff side springs possible and somewhat easier to return the building to its original position. This is because as the building moves sidewise it would require energy to move slightly upward and less energy for the springs or other devices to move it back.

I had a patent pending for this procedure. However, it had to be abandoned in view of a similar patent awarded in France in 1987.