Let's say some truths that we hide under the carpet, but come to the surface after every big earthquake. Do the newly built structures withstand the earthquake? Yes, they can withstand the seismic acceleration of design. The Greek area is divided into three seismic hazard zones. The values of design ground accelerations are 0.16g (percentage of gravity acceleration g) for the first zone, 0.24g for the second zone and 0.36g for the third zone. Yes, they can withstand these earthquake accelerations. However, historically earthquakes of the order of 1 g have been recorded in Greece with much greater territorial acceleration. What happens to these earthquakes that are greater than the design acceleration? The largest earthquake in the world had an acceleration of 2.9 g At these accelerations, the constructions have absolutely no luck That's why you need my patent. There are also projects of extreme importance such as nuclear power plants, hospitals, schools. In these projects, how do we prevent disaster?
The purpose of the modern seismic regulation is to construct structures that: a) In frequent earthquakes most likely to happen nothing will happen, b) In earthquakes of medium probability to occur will suffer small, repairable damage and c) In very strong earthquakes of low probability to occur we will have no loss of human life. So we should not use the term "absolutely" in seismic constructions. We should use the term "quality" constructions which means application of at least the requirements of all modern regulations. The quality of constructions and their safety is also a function of the economic situation of the countries, among other factors. It is understandable that poor countries cannot be compared to countries where they have strict modern seismic regulations. Conclusion… there is no absolute seismic design today, and we should not refer to absolute seismic design. So there is a great need today to invent a more modern anti-seismic design that meets the ultimate anti-seismic design, with lower construction costs.
Aparna Sathya Murthy, you are right and I vehemently agree with you.
I think according to the basis of the building, if it is strong, it can withstand.
The purpose of modern seismic regulation is to build structures that: a) In frequent earthquakes with a high probability of occurrence will not suffer anything, b) In medium probability earthquakes will suffer small, repairable damage and c) In very strong earthquakes with a small probability of happen we will not have loss of human lives. So we should not use the term "Ultimate" in seismic constructions. We should use the term "quality" constructions which means application of at least the requirements of all modern regulations.
I know that we do not directly compare the primary acceleration of the earthquake with the seismic hazard factors of the regulation (0.16g, 0.24g, 0.36g). The design of the structures is done with the design spectrum that takes into account, ground, depreciation, period of construction. We design primarily on rock with an acceleration of min 0.40g when the coefficient is 0.16g and 0.60g when the coefficient is respectively 0.24g. (from the type of spectrum Agn = ag.Sn2.50. Where S = 1.00 on the rock and 1.20 on category B soils etc. The n damping for the concrete is currently obtained 1.00. Yes, new buildings withstand have been designed correctly, with ductility (preferably) having some regularity (rigid) and the studies have been applied correctly.
The correlation of quantities such as "inertial stresses - damping forces - elastic forces - dynamic construction characteristics - construction ground interaction - required ground motion" is non-linear but can be calculated approximately in the design range. But there are too many unbalanced factors that can lead to disaster and in most modern seismic structures. The factors that determine the seismic behavior of structures are numerous, and in part probable. (The direction of the earthquake is unknown, the exact content of the seismic excitation frequencies is unknown, its duration is unknown.) Even the maximum possible accelerations given by seismologists, and determine the seismic design factor, have a probability of exceeding more than 10%. Asymmetrical floor plans and large openings that are increasingly required by architectural needs bring about changes in the behavior of buildings in response to earthquakes. Of course there are rare, but larger seismic stimuli than those of the design.
A reinforced concrete structure withstands high acceleration for a short time or low acceleration for a long time. But it can not withstand high acceleration with long duration. No construction can withstand construction ground coordination. For these reasons .... never say, never.
Currently, there is no such thing as earthquake-proof construction worldwide except Japan, but experts say that buildings could be much more resilient for little additional cost. By adding shear walls, cross braces, diaphragms, and moment-resisting frames that are central to reinforcing a building.
Dear Syed Haroon Ali
I have been researching seismic construction technology for over 14 years. I am the first person in the world to propose to join the base of the walls with the ground using an anchoring mechanism and a new method of anchoring and at the same time to apply compressive forces to the cross sections of the walls. The purpose of this research is to stop the deformation of the structures in order to stop the failures of the structures. To stop the deformity we must stop the causes that cause it. The earthquake imposes a ground acceleration which is transferred on the construction. The structure reacts to this displacement due to inertia, creating lateral forces on the columns and the walls where it rests. These lateral forces bend the trunks of the columns and the walls until they break. In addition to the bending which is the one cause of deformation the walls also receive a tipping moment which is the second cause of deformation. The bending of the trunks of the vertical support elements in combination with the overturning torque that they suffer, strain the joints with torques which, if they are large, break the beams and the columns and the walls. So if we stop the bending and the overturning moment of the vertical elements we have stopped the torques at the nodes and then the breaking of the beams. I stopped the torque of the walls by joining their sides to the ground, and I stopped the bending by imposing compressive forces on their cross sections. The anchoring mechanism helps a lot in this when elongated diaphragm walls are used instead of the columns, because they do not bend and are not easily overturned. What I am telling you is data and has been proven both experimentally and by simulation. The big question is why since this method is good for the response of structures to the earthquake is not used? The answer is simple. Yes, everything I suggested is correct, but every engineer who wants to use my method and my mechanism wants to know the anchoring strengths of the mechanism at different depths and in different soils. So what I need are experiments of the mechanism in the ground in order to compile a table with the strengths of the soil-mechanism relationship and anchoring depth. Of course all this alone without anyone's help! The perfect method of my video proposal
https://www.youtube.com/watch?v=IO6MxxH0lMU
Newly built structures do not necessarily resist earthquake. Unless the structures are designed for that purpose, they will not be able to resist earthquake.
Very Interesting and important query. Following to learn more from expertise.
Thank you Dr Ioannis for sharing!
To withstand collapse, buildings need to redistribute the forces that travel through them during a seismic event. Shear walls, cross braces, diaphragms, and moment-resisting frames are central to reinforcing a building. Shear walls are a useful building technology that helps to transfer earthquake forces.
Dear Faraed Salman
It is the most beautiful and correct answer I have heard about the existing construction technology!
The seismic energy and the energy that moves the universe is dynamically confronted, it changes form, it is diverted, it is damped, it is released, it multiplies, it is transferred but it is not lost because it is transformed into something else. Your reference to today's seismic technology includes mechanisms that react to seismic energy by creating attenuation because they convert kinetic energy into thermal energy, ... release energy through shear walls, or react dynamically.
All this is correct.
But something is not right.
We do not divert seismic energy out of the structure, but we recycle the seismic energy inside the body of the structure.
Among other things, what my design method and the mechanism of the invention do, is to deflect the forces of inertia out of the structure, sending these forces into the earth before they are transferred through the cross-sections to the load-bearing components.
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