Volume 41, Issue 1 January 2006
Building Sway Factors Being Studied; Results So Far On Par with Hypothesis
The University of Notre Dame, the Boundary Layer Wind Tunnel Laboratory at the University of Western Ontario and Skidmore, Owings & Merrill LLP in Chicago are collaborating on a study of the effects of wind on tall buildings and the effect of sway.
According to the study manuscript recently accepted for publication in the ASCE (American Society of Civil Engineers) Journal of Structural Engineering, the objective is “to correlate the in-situ measured response characteristics of tall buildings in full-scale, with computer-based analytical and wind tunnel models for advancement of the current state-of-the-art in tall building design.” To meet the objective, three tall buildings in Chicago were selected for observation that includes high-sensitivity force balance accelerometers that are mounted on opposite corners of the ceiling on the highest floor of the building to record the subtle shifts in infrastructure caused by wind. The data collected from each site is then compared to predictions of how each building is expected to act in cases of high wind—predictions made by elemental and wind tunnel models—and analyzed for discrepancies that would help identify and modify current design practices.
According to the most recent study manuscript, the hypothesis at the onset of the study was that each building would have a low torsional response and to date, the findings have supported that hypothesis to varying degrees. The wind tunnel predictions for Building 1 fell short of the East-West response but over calculated the North-South response, while Building 2 results were on par, though slightly conservative, with predictions. Observed responses of Building 3 “… distribute rather uniformly about the predicted wind tunnel values.”
While the study continues, results so far indicate that current model and analytical predictions can be used reliably to estimate the reaction of buildings made with uncoupled steel.
Ohio Court Rules in Subcontractors’ Favor on Tort Claims
Traditional limits on tort claims protect construction subcontractors, including glazing subcontractors, from claims of negligence leading to damages for delay, lost profits and other economic losses experienced by construction owners or others not in privity of contract with a subcontractor. In an October 26, 2005, 5-2 decision, the Ohio Supreme Court handed glazing contractors a major victory when it struck down an appeals court decision that allowed a construction owner to challenge these limits.
In the case decided by the Ohio Supreme Court Dublin Suites v. Shook, a construction owner sued for additional expenses and lost profits for delays allegedly incurred because of deficiencies in a subcontractor’s work. However, the subcontractor had deleted the provision for delay damages from its subcontract agreement with its customer and no contract existed between the subcontractor and the owner. An Ohio trial court ruled that an owner could not sue a subcontractor for tort claims based on economic losses, but the 10th Appellate District Court of Appeals in Ohio reversed the trial court’s decision.
Shook, the subcontractor, asked the Ohio Supreme Court to review the appeals court decision, and the American Subcontractors Association (ASA) filed a legal memorandum supporting this request on May 7, 2004.
After the court agreed to review the case, ASA filed another brief asserting that the right of clients to make claims for economic losses should fall within the four corners of the contract.
The name of the company that supplied the framing used in the cover image of the November 2005 issue was provided to USGlass incorrectly. The framing was supplied by Aluflam USA, which also provided the photo. We apologize for any confusion.
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