The bridge collapsed due to resonance. Science has refuted the most famous myth about why bridges collapse. Where can you see an example of resonance?

Quite often, to build a welding inverter, the main three types of high-frequency converters are used, namely converters connected according to the following circuits: asymmetric or oblique bridge, half-bridge, and full bridge. In this case, resonant converters are subtypes of half-bridge and full-bridge circuits. According to the control system, these devices can be divided into: PWM (pulse width modulation), PFM (frequency control), phase control, and there may also be combinations of all three systems.

All of the above converters have their pros and cons. Let's deal with each one separately.

Half bridge system with PWM

The block diagram is shown below:

This is perhaps one of the simplest, but no less reliable push-pull converters. The “surge” of the voltage of the primary winding of the power transformer will be equal to half the supply voltage - this is a drawback of this circuit. But if you look from the other side, you can use a transformer with a smaller core without fear of entering the saturation zone, which is also a plus. For welding inverters with a power of about 2-3 kW, such a power module is quite promising.

Since power transistors operate in hard switching mode, drivers must be installed for their normal operation. This is due to the fact that when operating in this mode, transistors require a high-quality control signal. It is also necessary to have a no-current pause in order to prevent the simultaneous opening of transistors, which will result in the failure of the latter.

A rather promising view of a half-bridge converter, its circuit is shown below:

A resonant half bridge will be a little simpler than a PWM half bridge. This is due to the presence of resonant inductance, which limits the maximum current of transistors, and switching of transistors occurs at zero current or voltage. The current flowing through the power circuit will be in the form of a sinusoid, which will remove the load from the capacitor filters. With this design of the circuit, drivers are not necessarily needed; switching can be carried out by a conventional pulse transformer. The quality of control pulses in this circuit is not as significant as in the previous one, but there should still be a no-current pause.

In this case, you can do without current protection, and the shape of the current-voltage characteristic is , which does not require its parametric formation.

The output current will be limited only by the magnetizing inductance of the transformer and, accordingly, can reach quite significant values in the event that a short circuit occurs. This property has a positive effect on the ignition and burning of the arc, but it also must be taken into account when selecting output diodes.

Typically, the output parameters are adjusted by changing the frequency. But phase regulation also provides some advantages and is more promising for welding inverters. It allows you to bypass such an unpleasant phenomenon as the coincidence of a short circuit with resonance, and also increases the range of regulation of output parameters. The use of phase control can allow the output current to be varied in the range from 0 to I max.

Asymmetrical or oblique bridge

This is a single-ended, forward-flow converter, the block diagram of which is given below:

This type of converter is quite popular both among ordinary radio amateurs and among manufacturers of welding inverters. The very first welding inverters were built precisely according to such schemes - an asymmetric or “oblique” bridge. Noise immunity, a fairly wide range of output current regulation, reliability and simplicity - all these qualities still attract manufacturers to this day.

Quite high currents passing through transistors, an increased requirement for the quality of the control pulse, which leads to the need to use powerful drivers to control transistors, and high requirements for installation work in these devices and the presence of large pulse currents, which in turn increase the requirements for - These are significant disadvantages of this type of converter. Also, to maintain normal operation of the transistors, it is necessary to add RCD chains - snubbers.

But despite the above disadvantages and the low efficiency of the device, an asymmetric or “oblique” bridge is still used in welding inverters. In this case, transistors T1 and T2 will operate in phase, that is, they will close and open simultaneously. In this case, energy accumulation will occur not in the transformer, but in the inductor coil Dr1. That is why, in order to obtain the same power with a bridge converter, double the current through the transistors is required, since the duty cycle will not exceed 50%. In details this system we'll look at it in future articles.

It is a classic push-pull converter, the block diagram of which is shown below:

This circuit allows you to receive power 2 times more than when turning on the half-bridge type and 2 times more than when turning on the “oblique” bridge type, while the magnitudes of the currents and, accordingly, losses in all three cases will be equal. This can be explained by the fact that the supply voltage will be equal to the “drive” voltage of the primary winding of the power transformer.

In order to obtain the same power with a half-bridge (drive voltage 0.5U supply), the current required is 2 times! less than for the half-bridge case. In a full bridge circuit with PWM, the transistors will operate alternately - T1, T3 are on, and T2, T4 are off and, accordingly, vice versa when the polarity changes. The values of the amplitude current flowing through this diagonal are monitored and controlled. To regulate it, there are two most commonly used methods:

Leave the cut-off voltage unchanged, and change only the length of the control pulse;
Change the cut-off voltage level according to data from the current transformer while leaving the duration of the control pulse unchanged;

Both methods can allow changes in the output current within fairly large limits. A full bridge with PWM has the same disadvantages and requirements as a half bridge with PWM. (See above).

It is the most promising high-frequency converter circuit for a welding inverter, the block diagram of which is shown below:

A resonant bridge is not much different from a full PWM bridge. The difference is that with a resonant connection, a resonant LC circuit is connected in series with the transformer winding. However, its appearance radically changes the process of power transfer. Losses will decrease, efficiency will increase, the load on input electrolytes will decrease and electromagnetic interference will decrease. In this case, drivers for power transistors should be used only if MOSFET transistors are used that have a gate capacitance of more than 5000 pF. IGBTs can only get by with a pulse transformer. More detailed descriptions schemes will be given in the following articles.

The output current can be controlled in two ways - frequency and phase. Both of these methods were described in a resonant half-bridge (see above).

Full bridge with dissipation choke

Its circuit is practically no different from the circuit of a resonant bridge or half-bridge, only instead of a resonant LC circuit, a non-resonant LC circuit is connected in series with the transformer. Capacitance C, approximately C≈22μF x 63V, works as a balancing capacitor, and the inductive reactance of the inductor L as a reactance, the value of which will change linearly depending on the change in frequency. The converter is controlled by frequency. , As the voltage frequency increases, the inductance resistance will increase, which will reduce the current in the power transformer. Quite a simple and reliable method. Therefore, a fairly large number of industrial inverters are built according to this principle of limiting output parameters.

Everywhere and every day we are accompanied by oscillatory systems in our lives.
The first impression in life is a swing. In this by no means simplest example, one can observe the dependence of the period of oscillation on the weight of the person swinging, as well as the problem of the movement of the swing being in phase with the external swinging force. Next, there is an acquaintance with musical instruments, one way or another using various kinds of oscillatory systems to produce musical sounds. Well, and in the end, all the electronics that completely embrace us, the main and indispensable unit of which is a quartz resonator - a refined oscillatory system, so to speak.
And at the same time, do we understand so much about this...
The clearest definition of an oscillatory system was given by Lord Kelvin when he discovered electric L-C oscillatory circuit in 1878. Having discovered that when an impact is applied to an oscillatory circuit, a sinusoidal (harmonic) damping process occurs, Kelvin stated that this is proof that a new, previously unknown oscillatory system is taking place.
Thus, we can formulate that an oscillatory system is a device that has a mechanism for converting impact into a harmonic damping process.
But what is interesting is that we cannot apply this definition to all known and used oscillatory systems. This happens because for these devices, which are definitely oscillatory systems (according to Kelvin’s definition), the mechanism itself for converting the shock into a sinusoid is not always known.
As for various types of pendulums, springs and oscillatory circuits, the mechanisms of their oscillation have been studied and discussed. However, there are oscillatory systems whose mechanism is unknown, despite their very wide application. Thus, until recently it remained unknown how, say, quartz resonators play the role of an oscillatory system.
The quartz resonator effect was discovered back in 1917, but for some reason they were embarrassed to admit its incomprehensibility. Due to this shyness, a model of a quartz resonator was proposed in the form of its equivalent to a certain combination of several virtual capacitors and inductors. For some reason this kind of modeling is called a scientific description of quartz resonators, this is all called theory, and this kind of scientific and educational literature exists visibly and invisibly.
It is clear that there are no virtual or real capacitors in quartz resonators, and all this scientific waste paper has nothing to do with these resonators. The fact is that in practice the frequency of a quartz resonator f 0 is determined by the thickness of the quartz plate h, and in its manufacture the following empirical formula is used:

f 0 = k / h, where (1)

k - technological coefficient.
So, in all the existing literature on quartz resonators, we will not find any mention of this empirical relationship, or any information at all about the connection between the natural frequency of the resonator and the dimensions of the plate.
60 years after the discovery of the properties of quartz plates, in 1977, it was discovered that not only quartz plates, but also objects from the vast majority of solid media (metals and alloys, glass, ceramics, rocks) are resonators. It turned out that the number of natural frequencies of these resonators is equal to the number of their sizes. So, a solid ball, say, made of glass, has only one size - diameter d, and, accordingly, one natural frequency f 0 , the connection between which, as it turns out, is determined by relation (1). A plate having a thickness h and sizes a And b, has three natural frequencies, each of which is related to the corresponding size by relation (1).
The presence of resonant properties of the objects listed above is revealed very simply, and even in several ways. In mine conditions, in the case of layered rocks, the simplest method is to press an elastic vibration field sensor (seismic receiver) to the object under study (roof rocks) and apply a short blow to the roof surface. The response to the impact will appear as a decaying harmonic signal. In laboratory conditions, this method is unacceptable, since it is very difficult to obtain the required impact parameters for small samples. In the laboratory, it turned out to be easier to use ultrasonic testing of the sample.
As it turned out, the resonant properties of a quartz resonator are not something unique and depend on the presence of the piezoelectric effect. The presence of the piezoelectric effect only simplifies the indication and use of this property. Thus, when studying the resonant properties of a piezoceramic disk, during the experiment it can be heated to a temperature exceeding the Curie point, at which the piezoelectric effect disappears, and its resonant properties will not change in any way.
However, if the scientists who studied quartz resonators managed to avoid searching for the physics of their resonant properties, then I had to take it seriously. The fact is that, despite the actually existing resonant manifestations, based on general considerations, a plate made of a homogeneous material should not exhibit resonant properties. Such a plate should not have a mechanism for converting the impact into a harmonic signal.
It cannot be said that this point of view is wrong, because there are materials from which objects are not resonators. Indeed, in materials such as plexiglass (plexiglass) and some others, this mechanism is absent. Plexiglas objects are not resonators. When impacted on a plexiglass plate, the reaction takes the form of a sequence of damped short pulses. That is, it fully complies with the provisions of generally accepted acoustics of solid media.
At the same time, as it turned out (in 1977), rock layers exhibit resonant properties, and using relation (1) it turned out to be possible without drilling (!) to determine the structure of the rock mass. Well, it is clear that it is very difficult to use a physical effect even though it is not difficult to prove the impossibility of its existence. In addition, the use of this effect in mines made it possible to create a method for predicting the collapse of roof rocks - a phenomenon that accounts for 50% of the injuries to miners throughout the world. But it was completely impossible to introduce into practice a technique based on such a dubious physical effect.
It took 4 years to find the difference between plexiglass and those materials from which objects are resonators. And somewhere in 1981, it was discovered that there is a difference, and it concerns the acoustic properties of the border zones of the vast majority of solid media.
It turned out that the acoustic properties of near-surface zones of media, objects from which exhibit the properties of resonators, are such that the speed of propagation of the front V fr during normal sounding it is not constant, and decreases as the front approaches the surface.
Figure 1 shows the case of normal sounding of a resonator plate 1 thick h. Addiction V fr (x), as well as minimum and maximum values V fr and zone sizes Δ h obtained from measurements made on many plates of the same material but having different thicknesses. Average speed Vfr.mid- this is the value that is obtained when determining the speed at the moment of the first entry.
In similar studies of plexiglass plates, the speed Vfr.mid when changing plate thickness h remains constant, from which we can conclude that in plexiglass (non-resonator plate) the zones Δh are missing.
When emitted by an emitter disk 1 harmonic signal, at the natural frequency of the sounded resonator plate f 0, that is, at resonance, emf. on the destination disk 3 disappears but appears on the destination disc 4 . This effect is called acoustic resonance absorption (ARA).

Rice. 1

Piezoceramic disk emitter 2 , sound plate 1 and piezoceramic receiver disks 3 And 4 are in liquid (water or oil).
Thus, at resonance there is a reorientation of the primary field emitted by the piezoelectric transducer 1 , in the orthogonal direction. The field rotation in the orthogonal direction occurs in the presence of near-surface zones Δ h.
Relationship between the presence of zones Δ h and rotating the field in the orthogonal direction is quite simple. The fact is that the speed of movement of any object or the speed of propagation of any process cannot change without external influence. Therefore, in fact, in the zone Δ h It is not the speed of front propagation that changes V fr, and her x -component, which is possible only if there is an occurrence y -component. In other words, the vector remains constant in magnitude, but in the zones Δ h the vector rotates V fr.
That is, it turns out that when a resonator layer is impacted, its surfaces become emitters of its own frequency f 0, and with a harmonic emitter, the resonator layer becomes sound opaque at resonance. But in both cases, under any influence, a field of elastic vibrations propagates along the resonator layer with a frequency f 0 .
Acoustic isolation of a resonator layer at its natural frequency from adjacent objects has been used for a very long time. Thus, it was noticed that if you put your ear to the ground, you can hear cavalry over enormous distances. In fact, it is not the cavalry that is heard, but the natural vibrations of the rock resonator layer, excited by the horse’s hooves. The very weak attenuation of the field propagating along the resonator layer is precisely a consequence of its acoustic isolation from the adjacent rocks.
When a rock mass is impacted during seismic exploration, the resulting field of elastic vibrations propagates along the rock bedding. This contradicts the fundamentals of seismic exploration, which states that the field resulting from an impact spreads out in all directions.
This is a very serious moment for understanding the operating principle of seismic exploration. It turns out that the signals received on seismograms come not from below, not from the depths, but from the side, since they propagate exclusively ALONG the bedding.
In the spectral analysis of seismic signals, it turned out that relation (1) is satisfied when the coefficient is k in the numerator equal to 2500m/s. In this case, the error in determining the thickness of the rock layer does not exceed 10%.
It must be assumed that a process oriented in the direction y with directed radiation in the direction x , is transverse. And thus, it can be argued that the own oscillatory process is formed by transverse waves, and the coefficient k is nothing more than the speed of transverse waves Vsh.
The discovery of essentially new, previously unknown oscillatory systems requires a restructuring of thinking. When at one time it was discovered that the Earth is a ball, the realization of this, as well as the transition from the geocentric to the heliocentric system, required a restructuring of the consciousness of the inhabitants of the Earth. However, this restructuring took several centuries, since this new information did not require any special changes in the algorithms of living conditions. Now the situation is somewhat different.
Due to the fact that our planet consists largely of rock layers, it turns out that in general it is a collection of oscillatory systems. This means that any impact on the Earth’s surface should cause a reaction in the form of a set of harmonic damped processes. If the impact is vibrational, then resonance phenomena become possible.
When considering resonant phenomena, there is a need to take into account a parameter characteristic of oscillatory systems - quality factor Q. The very definition of quality factor contains information about the colossal destructive potential of resonance. The quality factor Q shows how many times the vibration amplitude increases in the event of resonance.
Real values of Q for oscillatory systems implemented by geological structures located in the earth's thickness can reach several hundred. And if in the zone of such a high-Q oscillatory system there is an object that has a vibration (dynamic) effect on the ground, then the amplitude of the vibration of this object will increase exactly that many times.
However, the increase in vibration magnitude has certain limitations. These limitations are determined by the fact that at a certain vibration amplitude, elastic deformations are exceeded and destruction occurs. The soil that is exposed to vibration can collapse, and this is manifested by instantaneous, explosive subsidence, with the formation of a crater. When reinforcing the soil with various kinds of reinforced concrete structures (for example, a reinforced concrete dam for a hydroelectric power station), the studs on which the generator is attached to the dam may fail and break.
At small values of Q (say, up to 10), resonance manifests itself as increased vibration. This is unpleasant for the operating personnel; it leads to the formation of various kinds of backlash and imbalance in the operating mechanism, but such a low-Q resonance will not cause crushing, instant destruction.
If Q is significantly greater than the limiting value at which the vibration amplitude causes inevitable destruction, resonance can only exist for a short time. So, let’s say that with the standard vibration frequency of the dynamo 50 Hz, directly under this installation lies a geological structure that has a natural frequency of, say, 25 Hz with a quality factor Q = 200. Then, during the entire period of normal operation, vibration will be within normal limits. However, suppose that for some reason the machine needs to be stopped, and then, during the process of stopping, for some time, its rotation frequency will be close to the resonant one, 25 Hz. In the resonance zone, a smooth increase in the vibration amplitude will begin. And here the question is how quickly the rotor speed passes the resonance zone, and whether the vibration amplitude has time to increase to a destructive value.
It is easy to notice that here, as an example, the situation that developed at the Sayano-Shushenskaya HPP was considered. There, the vibration of hydraulic units in normal operating mode increased to unacceptable values. And when the decision was made to stop, the speed began to decrease very slowly. As a result, when passing through the high-Q resonance zone, the vibration amplitude managed to increase so much that the studs securing the hydraulic unit could not stand it. And, by the way, the recorders of the hydraulic unit showed an increase in vibration by 600 times.
A characteristic sign and harbinger of resonant destruction is an increase in vibration.
The first reliable evidence of the presence of such a precursor occurred during the Chernobyl accident. There, after all, it all started with a change in the reactor mode and, accordingly, the rotation speed of the units. At the same time, a vibration began, the amplitude of which began to quickly increase, reaching such a level that people began to leave this area in panic. The vibration was interrupted by a seismic shock (explosive destruction of the soil), noted by seismologists. And only half a minute after this, the destruction of the reactor occurred.
Subsequently, information appeared that this harbinger occurs during the destruction of various types of pumping stations. In the same way, when the vibration frequency of the compressor changes, the vibration amplitude suddenly begins to increase, ending with the equipment sinking into the ground. The cause of such an event is usually cited as either a terrorist attack or poor-quality piles on which the station stands.
Railway accidents often occur when, for no apparent reason, a train breaks into two parts, when suddenly, suddenly, an embankment collapses explosively, forming a depression, and instantly destroyed sleepers and pieces of rails fall into this funnel. It is at this moment of track destruction that the train breaks. However, in the car, which turns out to be the last one to pass through this zone, there is a strong vibration, which ends with the instant destruction of the embankment.
On August 13, 2007, such an accident occurred in the Novgorod region with train N166 Moscow - St. Petersburg. Eyewitnesses later described what happened: “...at first the train began to shake, followed by a bang. The guides, who have been working on this route for many years, later admitted that they began to say goodbye to life, since this was the first time in their memory that this had happened.” The key point is that witnesses felt a strong vibration before the impact.
On March 3, 2009, a six-story archive building suddenly collapsed in Cologne. As reported by Reuters, there was a rumble and strong vibration before the collapse. “The table I was sitting at shook and I thought someone had accidentally kicked it,” said one visitor to the archive. - After everything started to shake like during an earthquake" The house turned into a pile of bricks in just seconds. A police spokesman told reporters that "it looked like an explosion" with bricks, boards and pieces of cement scattered across the pavement in a radius of up to 70 meters. A metro line runs under the archive building, the tunnel of which also collapsed. The source of the vibration, as it turned out, was in the subway tunnel. This source was a drilling rig operating there.
The physics of resonant damage is discussed in detail in the works. Here it seems necessary to put next question. It is well known that an increase in the amplitude of vibration, ending in an explosion-like destruction, is uniquely associated with resonant phenomena. So why do we never hear the word “resonance” when investigating disasters that had such a precursor? The reason turned out to be purely psychological. According to the established opinion, there are NO oscillatory systems in the earth's thickness. And if there are no oscillatory systems, then there can be no talk of resonance.
If we nevertheless assume the assumption of resonance, then the question of the oscillatory system is inevitable. Because without an oscillatory system there can be no resonance.
Further, if we assume that the earth's strata really represent a collection of oscillatory systems, then this undermines the foundations of seismic exploration. After all, consideration of seismic exploration is possible only within the framework of its generally accepted model, according to which the earth's strata is a collection of reflective boundaries.
It doesn't matter whether seismic exploration provides information or not, because it is a colossal, multi-billion dollar business that cannot be touched. A business built on falsifications, but so huge that seismic exploration no longer needs anyone to confirm it.
Now there are probably no functioning scientists who would not know that it is a proven fact that our planet is a collection of oscillatory systems. But now they have the main task- pretend that they don’t know this. Any discovery to one degree or another negates the previous level of knowledge. Yes, indeed, if this point of view were mastered and accepted, the number of man-made disasters would decline. But alas, scientists don’t need this. For them, the main thing is to survive until the end of their lives at the level they have achieved, and so that no one crosses out the level of knowledge at which they reached their heights. And this certainly outweighs in importance for them all those catastrophes that could have been prevented.

LITERATURE

Glikman A.G. The effect of acoustic resonance absorption (ARA) as the basis of a new paradigm for the field theory of elastic oscillations.
Certificate from Northern Express conductors www.newsru.com/russia/14aug2007/train.html
Evidence of the destruction of the archive in Cologne www.gazeta.ru/social/2009/03/04/2952320.shtml
Glikman A.G. Vibration and resonance phenomena in our lives (what happened at the Sayano-Shushenskaya hydroelectric station)
Glikman A.G. Planet Earth as a set of oscillatory systems and man-made and natural earthquakes as consequences of this

The school physics course says that soldiers, passing in formation across a bridge, should stop marching and walk at a normal pace. Why such precautions? This command is given to the soldiers so as not to destroy the bridge. The fact is that if the frequency of the bridge coincides with the frequency of the marching step, then the bridge may collapse as a result of the resulting resonance. And this happens sometimes...

THE MOST COMMON RESONANCE

So what is resonance? In a simplified form, resonance is a harmonious relationship between different vibrations. Thus, when machines and mechanisms vibrate, nuts spontaneously unscrew. Or if two guitars are tuned in unison, then if you strike a string of one guitar, the same string of the other guitar will immediately begin to vibrate without any intervention, producing exactly the same sound. In order to verify the resonance phenomenon, the following experiment was carried out. Two pianos were installed at a certain distance from each other and connected with metal wire. Then one or another piece of music was performed on one of them. And the second piano began to repeat the same melody, although no one touched it.

The famous Fyodor Chaliapin sang so loudly that light bulbs in the concert hall shattered. This happened because the frequency of vibration of his voice coincided with the frequency of vibration of glass light bulbs. Resonance obeys neither the laws of space nor time. He seems to be from some other world, not subject to earthly laws. Resonance does not occur because objects are next to each other, because they have a certain harmonic relationship. These objects may be separated by thousands of kilometers, but the invisible connection between them will remain.

Moreover, scientists and researchers working in this branch of physics claim that everything that is located both in the Universe and in its individual structures, for example on Earth, is subject to the laws of resonance. Here is an example of the effect of resonance in human relationships. A person most often communicates with people similar to himself - intellectuals with intellectuals, drunkards with drunkards, etc. By the same principle, people find a life partner.

The principle of resonance was formulated in ancient times by the Greek thinker Hermes Trismegistus, without even knowing what law it was discovering: “Like attracts like.” Only those structures that are made from natural materials are in resonance with the vibrations of the Earth, i.e. made of wood, stone, etc. These, for example, include all the pyramids of the Earth. Therefore, during global cataclysms or pole shifts, they can withstand and survive, while all objects made of artificial material will be completely destroyed.

Resonance has many mysterious sides. So, if o parallel worlds talk about objective reality, then we sometimes sense and even feel the presence of representatives of these worlds on ourselves. One of the signs of parallel worlds is that parallel lines do not intersect, but sometimes this is not observed, and their worlds still intersect with our earthly world. Apparently, this happens because a certain resonant vibration arises at the border of the two worlds and violates the principle of parallelism.

RESONANCES OF TESLA AND SCHUMANN

One of the discoverers of the amazing and previously unexplored properties of resonance was the famous American scientist and inventor Nikola Tesla. The principle of resonance and vibration lay literally in all of Tesla's discoveries and inventions. New York, 1898. Conducting another experiment, Nikola Tesla turned on the device and began to observe how the water supply system vibrated under the influence of ultrasound, then the vibration spread to the walls, then the entire building vibrated. It vibrated more and more! It became clear to the scientist that in just a moment, something irreparable would happen. There was no time left to think, and Tesla, grabbing a hammer, hit his brainchild with it. Later, Nikola realized that he had almost destroyed an entire block. He realized that even the slightest vibration, if not allowed to die out, could cause the most terrible destruction. Thus, selective resonance was opened!

After this incident, Tesla told reporters: “To understand the secrets of the Universe, you need to think in terms of energies, frequencies and vibrations. Using the principle of resonance, in a few weeks I can cause such vibrations in the earth’s crust that it will fall and rise hundreds of feet, throwing out rivers from the riverbeds..." Tesla later argued that if you trigger a resonance corresponding to vibrations earth's crust, then he can tear an entire planet to pieces. In 1915, Tesla reported that his device was capable of causing destruction at any distance. “I have already built a wireless transmitter with which we can send electrical energy in any quantity over any distance.” So one of the versions of the Tunguska explosion can safely be called the result of Nikola Tesla’s experiment with his favorite resonator. But could Tesla direct energy to a specific location? Doctor of Technical Sciences Dmitry Strebkov is confident that this is quite possible - with two radars, you can detect any object on Earth.

Half a century later, the research was continued by the German physicist Otto Schumann. In collaboration with the doctor Herbert Koenig, he discovered the so-called standing electromagnetic waves located between the ionosphere and the Earth's surface. By the way, in 2011, Schumann waves were recorded by a space satellite at an altitude of 850 km. This space represents the Earth as a huge spherical resonator. Subsequently, these waves were called Schumann waves. If this wave, having completed a revolution around the globe, again coincides with its phase and enters into resonance with it, then it will exist for a very long time. Herbert Kenya stated that the frequency of this wave coincides with the range of alpha waves of the human brain.

Thus, a person lives, as it were, inside such a resonator, thanks to which Schumann waves stabilize his biological rhythms and normalize his life. These waves, so necessary for us, are excited magnetic processes on the Sun, by lightning discharges. The absence or weak activity of waves can cause loss of orientation, dizziness, headache. This is especially acute for elderly and chronically ill patients.

Due to the deterioration of the Earth's ecology, which is happening today, the Schumann frequency may change for the worse. And then physical body a person may lose contact with the frequency radiation of the Earth, which is fraught with disastrous consequences. But as long as people observe universal moral values, they will not have a negative impact on the programs embedded in them, they will be in resonance with the radiation of the Earth, with Schumann waves. If such conditions are regularly met, the Golden Age mentioned by Nostradamus can begin on Earth.

CHAERONIMUS'S MACHINE

A rather unique device was invented by Gallen Haeronimus, an American electronics engineer. It consists of an endovibrator and a metal plate. The apparatus of Gallen Haeronimus received a US patent in 1948 under No. 2482?773. The essence of his invention is that the “operator” tunes his brain to a particular person and, causing resonance, runs his fingers over a special rubber diaphragm.

Haeronimus inserted one by one photographs of the Apollo 11 astronauts going to the Moon into a special device in his “time machine.” Thus, he could monitor the condition of the astronauts throughout the flight. From the report: "... the most important and frightening thing is that the Moon is surrounded by a belt emitting lethal doses of radiation. It extends approximately 65 miles from the surface of the Moon and begins 15 feet from it. There has also been an increase in the oncological indicators of astronauts and a decrease in their life expectancy activity. This state lasted until they found themselves on the surface of the Moon."

"I INVENTED A THOUGHT RESONATOR!"

Georges de la Warre, a professor of physics from Oxford, sometimes did not leave the walls of the laboratory for months when conducting his mysterious experiments. Finally, the time came when he triumphantly exclaimed: “I have invented a thought resonator!” The capabilities of the resonator were not just unique - they were not limited by either time or space!

At one time, the scientist came to the conclusion that almost all objects emit electromagnetic radiation around themselves. Moreover, the frequencies of a part of this object are identical to the frequencies of the whole object. This primarily indicated that the connection between them does not disappear, no matter how far from each other they are. In the same way, a photograph of a person is closely related to its original.

And de la Warr found a way to obtain photographs of objects along with their radiation - for this purpose he invented a special camera. Studying the resulting photographs, the professor noticed that under certain conditions these objects contain minor differences from their photographic images. “Pictures show the state of objects in time,” a thought dawned on him, “and if you also use a resonator, then the photographs will appear timeless!” Unique experiments began. During one of them, de la Warr photographed... his own wedding day. So he filled two test tubes with his blood and his wife’s blood and, sitting comfortably, mentally imagined the distant year 1929 - the year of their wedding and clicked the shutter...

The photograph showed him and his wife - young and happy. And inspired by success, de la Warr began to place drops of blood from those who suffered from serious illnesses into the resonating field. After taking photographs, I looked through pictures of the affected organs. Now this invention has been adopted by doctors and is called magnetic resonance imaging.

Here is what the inventor himself says about this: “Blood is the only functioning time machine, and it is controlled by human thoughts. Our thoughts are electromagnetic radiation of certain frequencies; human hearts and embryos have similar frequencies. Everything that is in the flow of time, responds to our thoughts." It must be said that his discovery made a significant contribution to criminology. By photographing the blood of a suspect and his victim in the resonator field, one can obtain detailed photographs of the commission of a crime.

UNIVERSAL LAW OF COSMIC RESONANCES

The Universe with its countless galaxies, stars and planets is a single electromagnetic environment, and one of its laws is the Law of simple and complex resonances. Often the main cause of earthly cataclysms and disasters lies in the resonance of two or more cosmic cycles. It is generally accepted that these cycles are in acute resonance if they are shifted in time by no more than 3 hours. On resonant days, earthquakes, volcanic eruptions, hurricanes, epidemics, as well as sudden and drastic weather changes begin on Earth. In addition, the number of aviation, railway, and sea accidents is increasing, and computers are being disrupted. As for people, they experience malfunctions of the brain and psyche.

On April 10, 2010, a plane carrying Polish President Kaczynski and his wife crashed at a military airfield in the Smolensk region. In total, there were 96 people on board the Tu-134 - none of them survived. Lech Kaczynski was going to visit the Katyn cemetery near Smolensk that day.

Vladimir Pleskach, a specialist in resonance and biorhythms, is confident that this catastrophe is a consequence of a powerful resonance that arose due to the special ratio of the biorhythms of the passengers of the airliner and all sincerely mourning people. In other words, on board the Presidential plane there were passengers whose hearts and souls were filled with grief and pain for their compatriots who died in the spring of 1940 in Katyn. But what happened happened! Vladimir made every effort to defend the honor of those who died along with all the pilots who were at the extreme end of this tragedy. Here the crashed plane can be compared to the same collapsed bridge.

Vladimir LOTOHIN

TO HOME

Physicists have developed a model that can be used to estimate the critical number of pedestrians walking on the bridge, which will lead to its sharp swaying. According to the authors of a study published in Science Advances, their proposed model will allow the construction of safer pedestrian bridges in the future.

Despite the fact that the most modern computer modeling packages are now used when designing pedestrian suspension bridges, situations are still sometimes observed when, due to large quantity pedestrians on the bridge, it suddenly begins to sway violently. Sometimes these vibrations can be so strong that they cause unsafe situations and the destruction of parts of structures. The most significant examples are the opening of the Solferino Bridge in Paris in 1999 or the regularly swaying Millennium Bridge in London, which had to be rebuilt shortly after opening because of this.

A swing bridge is a classical oscillatory system in which walking pedestrians are sources of external periodic force. When the natural frequency of vibration of the bridge coincides with the frequency of the external force, the system comes into resonance, and the amplitude of vibration increases sharply. If there are many sources of external force and they all have the same frequency (that is, pedestrians take the same number of steps in the same periods of time), then phase synchronization can still occur between them, when everyone starts walking at the same time. It is phase synchronization that is usually called the main unaccounted reason in design, which leads to the occurrence of resonant oscillations on real bridges. Despite the relevance of the problem, all previous models describing such a mechanism could not explain the threshold effect of this phenomenon: when the number of pedestrians is less than critical, the bridge almost does not sway, but as soon as the number of pedestrians walking in step exceeds a certain value, a sharp increase in the amplitude of the transverse movements is observed. hesitation.

A group of physicists from the USA and Russia, led by Igor Belykh from the University of Georgia, proposed a new model that, in addition to other parameters, takes into account the biomechanics of the human body at the moment of taking a step. In the system under consideration, the bridge itself is an oscillatory system in which damped vertical vibrations arise under the influence of walking pedestrians. To describe a walking person, we considered two biomechanical models (a more complete one and its simplified analogue), which take into account that in response to the vertical vibration of the bridge, the person leans to the side and thus excites transverse vibrations.

Scheme of the physical system under consideration. On the left is a bridge in which walking pedestrians excite its vibrations; on the right is a person who reacts to the movement of the bridge, thereby causing its transverse vibrations

I. Belykh et al./ Science Advances

There is no exact analytical solution for the resulting system of equations, so the authors of the work used numerical methods to find solutions. Unlike all previous ones, the proposed model led to the emergence of a threshold effect. If all pedestrians are walking at the same pace, then as the number of people on the bridge increases, instability may suddenly occur. To confirm the model's work, physicists tested it to describe the sway of London's Millennium Bridge, for which the exact number of people that led to the resonance is known - 165.

Moreover, the same effect was observed in the case when the step frequency of different pedestrians varied slightly, which brings the model even closer to reality. In addition, it turned out that the presence of phase synchronization is critical only for vibrations of very heavy bridges (like the Millennium Bridge, which weighs about 130 tons) with a large amplitude. Excitation of oscillations with a small amplitude is possible even without phase synchronization. Such cases have also been observed in reality, and scientists call the change in step speed when moving along a bridge one of the possible mechanisms for excitation of vibrations, even the only source.

In their work, the physicists expressed the hope that the model they proposed would be used in the future for more accurate design of safe suspension and pedestrian bridges.

To diagnose damage that appears on large bridges, they are now used various methods, based on the study of mechanical characteristics and detection of defects using ultrasound. Recently, drones have been used to inspect bridges, including their underwater parts.

Alexander Dubov

under the hooves of a squadron of guards cavalry

The Egyptian bridge across the Fontanka River in St. Petersburg collapses.

Imagine that you are standing on a swinging wooden slatted bridge. It is clear that if you start swaying in time with the swaying of the bridge, the bridge will begin to sway even more.

Real modern bridges also, in fact, oscillate imperceptibly to the naked eye. Architects know that the phenomenon of resonance (that is, the coincidence of the natural frequency with the frequency of external influence) can lead to catastrophic consequences.

Egyptian chain bridge over the Fontanka

So, on February 2, 1905, the Egyptian Bridge in the city of St. Petersburg collapsed when a horse squadron was passing across it. It is believed that the cause of the incident was that the riders, while prancing on their horses, came into resonance with the bridge’s own vibrations.
In school physics lessons, when studying the phenomenon of resonance, they often give an example of this destruction, when a squadron of the Horse Guards Regiment passed “in step” across the bridge in one direction, and 11 sleighs with drivers in the opposite direction.
Typically, a military squad takes 120 steps per minute, and this frequency (2 Hz) coincided with the natural frequency of the structure. With each step, the range of vibrations of the span increased, and finally the bridge could not stand it. The bridge resonated and collapsed. It was one of five suspension bridges in the city.
The entire deck of the bridge, along with the railings and fastenings, broke the chains and broke part of the cast-iron support, broke through the ice and ended up at the bottom of the river.
Fortunately, there were no casualties and everyone managed to get ashore. According to official information, there were no serious injuries.
Subsequently, the military was forbidden to walk across the bridges in lockstep. There was even a special command: “Step at random!”

Egyptian bridge over the Fontanka River. The bridge got its name because of its unique design.

Currently, the sphinxes are all that remains of the first bridge. Now this bridge is neither chain nor suspension.

And in 1940, the Tacoma Bridge in the USA collapsed due to resonant vibrations. The photo shows how it was “twisted”.