Environmental Vibration Effects and Countermeasures - A Complete Guide

　In the buildings and surrounding environment in which we live, vibrations are constantly occurring, including in areas where people cannot feel them, and such vibrations are called environmental vibrations. In this article, we will explain the effects of and countermeasures against environmental vibration in an easy-to-understand manner.

What is environmental vibration?

　The Architectural Institute of Japan defines the term environmental vibration as follows The term "environmental vibration" is defined as "the daily vibration of the ground, buildings, and other boundaries that surround us in a certain extent, and therefore excludes specific vibration sources alone and major earthquakes, but may be included in a broader sense. Thus, specific vibration sources alone or major earthquakes are excluded, but may be included in a broader sense." In other words, of the various vibrations we experience in our daily lives, vibrations that particularly affect our living environment can be considered environmental vibrations.

For example, the following types of vibration are included in environmental vibration

• Traffic vibration caused by road vehicles and railroads
• Vibration due to construction work
• Vibration from factory production machinery
• Swaying of buildings due to wind and long-period seismic motion
• Vibration from equipment
• Vibration of mane in stadiums and concert halls, etc.
• Walking vibration inside the building
• Vibration when ascending and descending stairs, etc.

Vibration sources of environmental vibration

Vibration sources of environmental vibration can be categorized as follows

　As shown in Figure 1, sources of environmental vibration can be largely divided into external and internal vibration sources. As for external vibration sources, there are artificial and natural vibration sources originating from human activities. For more details, please refer toCauses of Vibration - A Complete Guidefor more information.

Figure 2 shows some specific examples of various vibration sources.

Direction of environmental vibration shaking

There are two main directions in which environmental vibration can swing

• Vertical (up and down) direction: mainly vibration of the building floor
• Horizontal: Shaking of the entire building

Figure 3 shows an image of the difference between vertical and horizontal vibration.

As shown in Figure 4, the direction of vibration that primarily affects different vibration sources varies.
For more information, please contactDifference between "Horizontal Vibration" and "Vertical Vibration" of Buildings - A Complete Guidefor more information.

Effects of environmental vibration

　Environmental vibration does not include large vibrations such as earthquakes that can cause severe damage to structures, but it is believed to affect the human body and equipment when repeated. This section describes the types of effects.
Effects on the human body
1. psychological impact:
　　Discomfort and anxiety
2. physiological effects:
　　Circulatory, respiratory, and gastrointestinal effects
　　Autonomic nervous system imbalance
　　Insomnia and depression
　　Symptoms like motion sickness

These can cause a decrease in quality of life and a decrease in work efficiency and productivity.

In addition, environmental vibration affects the machine.

Impact on equipment
1. physical impact:
　　Increase in defect rate of produced goods
　
　As described above, environmental vibration can adversely affect both humans and machinery, causing a variety of health and economic challenges, so it is essential that appropriate countermeasures be taken.

Environmental Vibration Countermeasures

As a way to prevent the effects of environmental vibration, various countermeasures can be considered for each situation. In this issue, examples of actual countermeasures are shown below.

In what place?　What kind of shaking?	Causes of shaking	Problems due to shaking
Lateral sway (horizontal vibration) of the entire building Example of environmental vibration improvement in an office building caused by high winds Case study of hotel environmental vibration improvement due to high winds Case Study of Environmental Vibration Improvement in a Commercial Building Caused by High Winds	High wind traffic vibration, etc.	Anxiety and discomfort due to shaking
Floor swaying (vertical vibration) in the building Offices, residences, factories, etc. Example of environmental vibration improvement in a factory using production equipment Example of environmental vibration improvement in a factory using pumps A case study of environmental vibration improvement in an office due to road traffic vibration (1) Case Studies of Environmental Vibration Improvement in Offices by Road Traffic Vibration (2) Case Study of Environmental Vibration Improvement in an Office by Road Traffic Vibration (3) Example of improvement of environmental vibration in an office due to railroad vibration Example of environmental vibration improvement in an office with adjacent factory building and production equipment Case Study of Environmental Vibration Improvement in an Office by Walking Vibration (1) Case Studies of Environmental Vibration Improvement in Offices by Railway Vibration (2) Case Study of Environmental Vibration Improvement in an Office by Walking Vibration (3) Case Study of Environmental Vibration Improvement in an Office by Walking Vibration (4) Case Study of Environmental Vibration Improvement in an Office by Walking Vibration (5) Example of improvement of environmental vibration of a house due to road traffic vibration Example of countermeasures against environmental vibration in a theater by Tatenori Case study of environmental vibration in a gymnasium caused by fitness vibration	Equipment Machinery Traffic Vibration Walking Vibration Fitness, etc.	Decreased habitability workability due to discomfort Vibration causes malfunction of precision equipment, etc.
Bridge structure (vertical oscillation) Stairs, pedestrian bridges, connecting corridors, crossing corridors, etc. Example of staircase vibration environment improvement (1) Examples of staircase vibration environment improvement (2) Example of staircase vibration environment improvement (3) Example of Vibration Environment Improvement in a Crossing Corridor	Walking vibration, etc.	discomfort Difficult to walk through

Appropriate measures are essential to maintain a comfortable living environment. It is important to implement the best solution for each individual situation.

References Goto and Hamamoto: Easy-to-understand knowledge of environmental vibration