Vibration Research
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Although we consult in the area of vibration damage, we also carry out research on vibration effects. We make these studies available to the scientific public through our companion web site https://vibrationdamage.com and the free resources offered there.The impact of these studies is illustrated by the hundreds of engineers, vibration specialists and academics who have downloaded the free Construction Vibration Damage Guide (CVDG), purchased its comprehensive version, the Construction Vibration Damage Guide Professional Edition (CVDG Pro), used the CVDG in their teaching, or referenced these works in their own studies. Following is a partial summary of some of the findings we have contributed to the field of vibration effects. Vibration Damage Occurrence and Prevalence
There are no published studies which give any idea of the actual prevalence of vibration damage in construction and blasting. We have collected data from almost 2700 registrants of the CVDG, as of this writing in 1/23. The data tell us many things about the causes of vibration damage. For example, damage reports make up about 55% of the registration reasons, as seen above. Blasting and vibratory compaction of roads are the two most common reported causes of damage to structures. We have examined these data for over 600 different variables or combinations thereof to ascertain the relationships between the variables. Visitors to Vibrationdamage.com can view some of these results online and in the CVDG, while a much more extensive analysis of the data can be found in the CVDG Pro. As a whole, the data indicate that vibration damage is both common and underreported, in the U.S. and over 100 other countries.
While there are many studies which characterize vibrations from various parts of construction projects or blasting, there are few, if any, which tell us about the critical parameters of frequency distribution, duration and repetition of vibrations for an entire project, backed up by extensive video documentation of the operations occurring. We have provided that for one road construction project. Contrary to expectations in the literature, the majority of the vibrations observed were below 40 Hz in dominant frequency, making them far more dangerous from a damage probability standpoint than had been expected. We have also shown with well-documented vibration data that construction vibration can provide tens to hundreds of times as much vibration exposure, depending on operation, as worst case blasting at an active surface mine.
Approximate ages of damages from construction vibration are often estimated from visual inspections of crack edges. Those cracks claimed to have "eroded" edges are characterized as "old" or "pre-existing", while those with "sharp" crack edges are seen as "new". Our careful research comparing crack edges of cracks of exactly known age shows that, while such characterizations are common, they are essentially unreliable in any setting, as crack edge aging is so slow in most environments as to make such conclusions meaningless. These are just some of the questions on which our research has had an impact. We are constantly trying to understand other aspects of construction vibration effects and expect to provide more information in the future from our research.
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Send e-mail to drzeigler@silchemy.com with your questions or comments about this web
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Whole Project Vibration Properties
Damage Age Estimates