Richard J. Driscoll
Consulting Engineer
Structural & Foundation Engineering
Most people understand that earthquakes can produce catastrophic damage to the built environment. However, given that large earthquakes are relatively rare, and that the television news cameras typically move on a few days after any disaster, a lot of people’s understanding of the effects of earthquakes may be shaped more by bad disaster movies than …
Continue reading “What Everyone Should Know About Earthquakes and Structures”
When structural systems are used to retain in-situ soil during excavation, the resulting soil pressures are difficult to accurately predict. In addition to the uncertainty inherent to soil materials, and the inability to fully measure those properties, the pressures on an excavation support system or permanent foundation elements that similarly retain in-situ soil and any …
Continue reading “When to Use Soil-Structure Interaction for Excavation Support Design”
Having projects in the urban environment representing a large proportion of my career experience, I am always a little surprised when I encounter design professionals and contractors who do not fully appreciate the challenges and constraints associated with building on urban sites. While a lot of design professionals, contractors and other stakeholders have urban project …
Continue reading “Site-Structural Engineering for the Urban Environment”
As reported by the United States Geological Survey and various news organizations, a magnitude 4.1 earthquake occurred outside Dover Delaware on November 30, subjecting much of the mid-Atlantic region to weak to light shaking. Assuming the magnitude is not revised down, it would be tied for the largest magnitude earthquake in Delaware history. No damage …
Continue reading “Delaware Earthquake or Earthquakes Can Happen Anywhere”
Traditionally, designers of temporary structures for use in construction had little guidance binding on their designs. Some owners, particularly infrastructure operators, provided standards and guidelines that permitted increased allowable stresses for certain temporary conditions. Sometimes the increased allowable stresses were limited to new materials or were subject to other stipulations. However, this practice came from …
Continue reading “Should Temporary Structures be Designed with Higher Allowable Stresses?”
I often find a lot of owners want to cut corners when constructing or repairing deck structures (decks, porches, balconies, etc.) by neglecting code requirement or working without permits, among other things. They assume that these structures require less care because they are accessory to and thus less important to the building. The reality is that decks are …
Continue reading “Another Deck Failure…No Injuries, This Time”
Nate’s Silver’s book, The Signal and the Noise (The Penguin Press, New York, 2012) was released in the run-up to the 2012 election. Silver and the FiveThirtyEight.com project were well on their way to accurately predicting most of the electoral college and Senate results and there was a good deal of interest and controversy in the political media regarding …
