In most of our nation’s cities, urban construction can be challenging. The
safety and protection for the traveling public is a top priority of engineering and public works departments.
A convention center, with 45-foot tall earth retention system was
constructed adjacent to several city streets. The earth retention system
was designed to use two systems consisting of soldier pile and lagging
above sheet piles. Within days of completion of the earth retention
system, a 400 foot long crack, with both horizontal and vertical deflection,
was observed in the street. In addition to the street damage, several
underground utilities in a vital downtown corridor were vulnerable to
damage; including a 40” brick combined sewer, two chilled water lines, a
gas main, a telephone duct bank and water mains.
NTH was contracted by the City to review documents and site conditions
related to construction activities for the convention center and damage to
the adjacent city street. NTH performed an evaluation of the information
provided by the City and contractors as it related to the observed
settlement and resulting pavement damage to determine the cause.
In addition to the review of plans, specifications and construction
documents (inclinometer readings, survey data, daily field reports, etc.),
the evaluation included calculating the anticipated amounts of movement
for the earth retention system.
NTH also attended several meeting with city and county personnel, law
departments, utility directors, and contractors. The temporary and
permanent repair procedures were discussed at these meetings. Through the discussions held at these meetings, the City was absolved of any responsibility to the damage, requiring others to pay for repairs.