Lyon County Middle School

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We provided comprehensive structural engineering assistance to the legal team representing the designers of an Addition to an existing middle school.  Soon after the Addition was opened unusual and widespread cracking of the exterior brick and concrete block masonry walls was reported.  That cracking continued to grow in size and frequency over the next few years to  the point where the building was judged unsafe for occupancy and closed.

The causes of the cracking were determined to be a combination of alkali carbonate reactivity and alkali silicate reactivity in the concrete foundations.  The resulting expansion of the concrete foundation elements resulted in the observed cracking of the exterior brick and block walls supported thereon.

The Addition was removed and replaced, and the case was successfully mediated.

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