By Jim D’Aloisio | Wednesday, May 3, 2017
A 2016 bill introduced in the New York State legislature, requiring periodic parking garage inspections by licensed professional engineers, was vetoed by Governor Andrew Cuomo for technical reasons. However, the governor agreed with the concept, and two legislators are now drafting rules to require periodic inspections by structural engineers.
Point taken: having an inspection done on a regular basis by a qualified engineer is sound advice.
Parking garage collapses in Wisconsin, in Syracuse, New York, and most recently in Johnson City, New York, among other locations, have confirmed the importance of periodic inspections. Most conditions of deterioration that can lead to failure can be identified either by visual observations or by the use of acoustic delamination detection methods such as hammer sounding, chain dragging, or impact wheel. In some rare cases, hidden states of deterioration, possibly coupled with design limitations and/or construction defects, create hazardous conditions with no visually apparent indications of distress on the surface of the structure. An engineer with experience in assessing such structures, who knows when to probe beyond the surface, is your best bet to minimize the potential for sudden, catastrophic collapses.
At this year’s Structures Congress (April 2017, Denver, Colorado) I presented a paper that I developed entitled “Structural Building Condition Reviews: Beyond Distress.” This was based on lessons learned during my 25 years of performing structural condition reviews and collapse investigations. During that time I encountered a few structures that contained, or had contained, conditions of severe structural inadequacy that did not reveal themselves through any type of damage, distress, or deterioration on the surface. Although these conditions are fortunately very rare, I can testify to their existence. To maximize the possibility of identifying such hidden defects without performing an unnecessary amount of intrusive and expensive investigations, we have developed a list of 12 considerations when assessing an existing structure.
In addition to reducing the chances of a catastrophic event, a good parking garage condition review can identify latent conditions that would best be addressed before they become more serious. Such a review would also recommend cost-effective maintenance activities such as drain repairs, application of concrete surface sealers to reduce the absorption of chlorides, when appropriate, and review other considerations such as lighting, signage, condition of nonstructural elements, aesthetics, and snow removal. The financial “sweet spot” is to provide the optimal level of ongoing review, maintenance, and repair for the parking garage to operate in a safe and functional manner at the lowest long-term cost.