Browse by Application
Browse by Application
Browse by Product Type
Browse by Product Type
How Vibrations Affect Both Structures and Humans
Vibrations are an interesting mechanical phenomenon that can cause pleasure or pain, depending on the specifics of the vibration. A night spent at the symphony and an afternoon spent at work while a jackhammer demolishes the sidewalk outside your window are both experiences driven by vibrations. One is a relaxing retreat from your busy work week, while the other may drive you nuts and negatively impact your productivity.
The vibration effects on structures and humans have been studied fairly extensively, and we know much more now than we did just a couple of decades ago. Understanding vibrations and their effects on anything with mass will underscore how important noise and vibration control are in our world.
What are vibrations?
Vibrations are all around us. Nearly every motion creates some type of vibrations, whether we recognize them or not. But what are vibrations? Vibrations are oscillations that occur about an equilibrium point. Simple, right? If you’ve ever watched someone jump on a trampoline, you’ve got a great visual reference to get you started understanding vibrations. The jumping surface is taught at rest, which is its equilibrium point. When someone jumps up and down, the trampoline vibrates. The surface moves up and down, eventually returning to its equilibrium. It’s very similar to what you see when someone plucks the strings of a musical instrument. As the energy waves are transferred to the air and structures around the source of the vibrations, those energy waves can create sounds, and the vibrations can transfer through other structures and bodies.Vibration effects on structures
Many everyday vibrations have little or no effect on structures, but some can cause the structure to weaken or even fail entirely. Throughout history, we’ve built structures that stood the test of time, and we’ve built structures that unexpectedly came down in remarkable fashion. We’ve learned a bit about resonance in studying the doomed structures and what caused them to collapse. Resonance occurs when the frequency of a vibration matches and forces the structure to vibrate at its natural frequency. The natural frequency is the frequency of the material when not exposed to outside drivers or vibration dampers. A vibration damping material is anything that provides resistance to the oscillations and causes the vibrating material to return to its equilibrium point. The natural frequency of any object is defined by its mass and rigidity. The easiest way to demonstrate natural frequency is by using tuning forks as an example. The specific design of each tuning fork is such that the natural frequency corresponds with the note it’s tuned to. Changing the mass or rigidity of the tuning fork will change its natural frequency, and therefore the note produced by the fork. Prolonged exposure to damaging vibrations can cause nails to move, bolts to loosen, and the foundation to crack. In other words, nothing good. When vibrations occur in structures, whether they’re produced by traffic, construction, music, or simply foot traffic in the building’s hallways, they can have an effect on the building’s structural integrity. They can also have an impact on the humans living and working inside.Vibration effects on humans
Most of us find the effects of sound vibration on the human body to be pleasant in nature. Our stress levels decrease, and we feel the urge to tap our toes and nod our heads. In fact, there is a body of evidence that suggests music therapy can be incredibly beneficial in treating several spiritual and physical ailments. As great a prospect as music therapy is, not all vibrations are helping and healing. Some vibrations can have detrimental effects on our bodies and minds.Physical effects
People exposed to high levels of vibrations on a regular basis can experience adverse physical effects of vibration on the human body.- Those who regularly use electrical hand tools like grinders and drills can damage nerves and muscles, leading to chronic numbness and tingling.
- When we’re exposed to whole body vibrations due to standing on or riding in vibrating machinery, we can experience a whole host of additional symptoms, including chronic back pain, motion sickness, and sleep disturbances.
- Many vibrations arrive with the presence of very loud sounds, which can cause us to experience issues related to hearing loss or tinnitus, which is a persistent ringing in the ears when no sound is present. The extent of the damage can vary based upon the volume of the noise and the frequency of exposure.