Environmental vibration evaluation is performed by analyzing the acceleration data of vibration recorded in measurements and then comparing it to various evaluation criteria. There are several evaluation criteria and methods, which are used depending on the application and object. What kind of situation will it be used for? What kind of evaluation? Some typical examples are introduced below.
Vibration Regulation Law (Ministry of the Environment)
Laws and regulations enacted in 1976. Prefectural governors and mayors of cities and special wards designate areas to be regulated with respect to vibration (designated areas), and different regulatory standards, etc. are established for each of the three regulatory targets. Evaluation is based on the vertical vibration level (vibration acceleration level plus correction for human sensation).
1. Plant and Office Vibration
Produces loud vibrations in designated areasspecified facilitiesnote 1For factories that have installed the
| Area/Hours | daytime | at night |
|---|---|---|
| From 5:00 a.m. to 8:00 a.m. From 7:00 p.m. to 10:00 p.m. | From 7:00 p.m. to 10:00 p.m. Between 5:00 a.m. and 8:00 a.m. the next day | |
| Type 1 Zone | 60 to 65 dB | 55-60 dB |
| type II zone | 65 to 70dB | 60 to 65 dB |
1 Specified facilities: Facilities installed in factories or workplaces that generate significant vibration and specified by a Cabinet Order (1. metal processing machinery; 2. compressors; 3. crushers, grinders, sieves and classifiers for earth, rocks or minerals; 4. weaving machines; 5. concrete block machines; 6. (6. Wood processing machinery, 7. Printing machinery, 8. Rolling machines for rubber or synthetic resin kneading, 9. Injection molding machines for synthetic resin, and 10. Molding machines).
2. Construction work vibration
Produces loud vibrations in designated areasspecified construction work*2for the construction site when the project is being carried out.
| Area/Hours | Zone 1 | Zone 2 |
|---|---|---|
| Vibration magnitude | Not exceeding 75 dB at the property line | |
| work hours | Not to take place between 7:00 p.m. and 7:00 a.m. the next day. | Not to take place between 10:00 p.m. and 6:00 a.m. the next day. |
| working period | Less than 10 hours per day | Not more than 14 hours per day |
| Within 6 consecutive days | ||
| work day | Not on Sundays or other holidays. | |
2 Specified construction work: Work that generates significant vibration among work performed as construction work, as specified by a Cabinet Order (1. Work using a piling machine, piling machine, or piling and piling removal machine; 2. Work to destroy buildings and other structures by using steel balls; 3. Work using a crusher; 4. Work using a breaker).
3. Road traffic vibration
Subject to road traffic vibration in designated areas
| Area/Hours | daytime | at night |
|---|---|---|
| From 5:00 a.m. to 8:00 a.m. From 7:00 p.m. to 10:00 p.m. | From 7:00 p.m. to 10:00 p.m. Between 5:00 a.m. and 8:00 a.m. the next day | |
| Type 1 Zone | 65dB | 60dB |
| type II zone | 70dB | 65dB |
Reference: Ministry of the Environment Vibration Regulation Law Pamphlethttps://www.env.go.jp/content/000190208.pdf
AIJES-V0001-2018 (Architectural Institute of Japan Environmental Criteria: AIJES-V0001-2018)
It presents the Occupant Performance Evaluation Criteria established by the Architectural Institute of Japan to evaluate daily vibration in buildings from the perspective of habitability.The first edition was published in 1991, followed by the second edition in 2004, and the third edition in 2018. The third edition evaluates the shaking of buildings and floors caused by human activity, equipment, traffic, and high winds. The criteria are based on the maximum vibration acceleration in the 1/3-octave band.
The performance evaluation chart has seven levels from V-I to V-VII, and the range between the curves is rated as V-00 (Figure 1). The evaluation levels are classified according to the degree of bothersomeness and discomfort of the shaking (Table 4). For example, V-III is rated as "somewhat bothersome and not very bothersome.
In the previous guideline (AIJES-V0001-2004: 2nd edition), the evaluation curve was based on the probability of human perception of vibration (Figure 2), and the number V-00 indicates the percentage of people who perceive each level of vibration, for example, V-10 represents the level perceived by 10% people. Since the perception of vibration is not necessarily a complaint about vibration, it is necessary to consider the environment in which the building is used and other factors that are the subject of the evaluation.Click here for an actual evaluation example.
Fig.1-1 Performance evaluation drawing (floor of a dwelling etc.) Fig.1-2 Performance evaluation drawing (floor of an office etc.)
(AIJES-V0001-2018)
Table 4: Description of Rating Levels
Figure 2 Performance evaluation curve (AIJES-V0001-2004)
References: "Occupant Performance Evaluation Criteria for Building Vibration and its Commentary," edited by the Architectural Institute of Japan, 2018.
Building Society of Japan (ed.), "Occupant Performance Evaluation Guideline for Building Vibration and its Commentary," 2004
Pedestrian Bridge Planning and Design Guidelines (Japan Steel Construction Association)
The aforementioned occupant performance evaluation criteria are for general floors. This standard is used to evaluate pedestrian bridges, stairways, and connecting bridges (crossing corridors). The values are proposed as various vibration magnitude limits (upper limits that do not cause noticeable adverse effects or damage to human health) in "Pedestrian Bridges in the Future: Guidelines for Planning and Design of Pedestrian Bridges Friendly to Persons with Disabilities," edited by the Japan Steel Construction Association (Note: This is one of the main research results, and no unified consensus magnitude limit has been reached yet). is not yet available), evaluated at the maximum value of vibration acceleration in the 1/3-octave band. Pedestrian bridges, stairways, and connecting bridges (crosswalks) have a smaller applied load than building floors and are more prone to large vibrations than ordinary floors due to their slender construction. Therefore, unlike the occupant performance evaluation, the evaluation of pedestrian bridges is based on the pedestrian's own perception of the vibration during use, so the evaluation is based on walking and standing conditions.Click here for an actual evaluation example.
Fig. 3 Vibration magnitude limits for various types of vibrations
Reference: Steel Construction Association of Japan, "Future Pedestrian Bridges - Planning and Design Guideline of Pedestrian Bridges Friendly to Supporters," 199.
Environmental coefficient (Architectural Institute of Japan)
The environmental coefficients are based on the international standard ISO 2631-2 Annex A (1989). It is evaluated based on the effective value of vibration velocity in 1/3 octave band. The evaluation is performed by multiplying the environmental coefficient of 1, which is the reference curve, by a factor depending on the use of the building (Fig. 4, Table 5).Click here for an actual evaluation example.
Figure 4 Environmental coefficient curve
| environmental coefficient | use |
| 1 | precision work area |
| 2 | Housing & Hospitals |
| 4 | Office/School |
| 8 | workshop |
References: "Reinforced Concrete Structural Calculation Criteria and Commentary" edited by Architectural Institute of Japan, 2018
VC Standards (Insutitute of Environmental Sciences (IEST))
The VC standard (curve) was originally created for use in the semiconductor field in the early 1980s and was standardized by IEST (Institute of Environmental Science and Technology) in 1993. It is now used as an acceptance criterion for precision instruments in various fields. Initially, four levels were created, VC-A through D. Later, VC-E was added. Later, VC-E was added, followed by VC-F and VC-G. The rating curves are based on the ISO 2631-2 reference curves from which the environmental factors described above were derived, with VC-A at 50 μm/s, half the reference curve, and VC-B at 25 μm/s, even half the reference curve. It is evaluated based on the RMS value of the vibration velocity in the 1/3 octave band.
Figure 5 VC Criteria
| valuation basis | use |
|---|---|
| VC-A | Optical microscope about 400x Electronic balance |
| VC-B | Exposure and inspection systems for line widths up to 3 µm |
| VC-C | Optical microscope of about 1000x magnification, exposure and inspection equipment for line widths up to 1 µm |
| VC-D | Equipment using electron microscopes and E-Beam systems |
| VC-E | Equipment using laser-based systems or ㎚ unit E-Beam systems, a very difficult standard to achieve |
| VC-F | Suitable for extremely quiet research spaces. Almost unattainable standard, not recommended for use as a design criterion. |
| VC-G | Suitable for extremely quiet research spaces. Almost unattainable standard, not recommended for use as a design criterion. |
- References:Institute of Environmental Sciences (IEST),.
- Appendix C in Recommended Practice RP-012,.
- "Considerations in Clean Room Design," IES-RP-CC012.2,.
- Institute of Environmental Sciences, Rolling Meadows, IL, 2005