According to The New York Times, Sept. 21 St, 2009, Business Section, The Ocean Tower on South Padre Island, Texas Golf Cost, recently known as “The Leaning Tower of Padre Island” will be demolished. This was announced by its developer.
The Ocean Tower, considered to be the most luxurious tower in the region, a 31-story condominium project with 151 units, spa and other amenities, is structurally complete and in the interior finishing stage.
It is also sinking more rapidly than the attached parking garage structure, causing cracks in beams and columns.
Not intended to be an evaluation of this particular matter without knowledge of the design parameters, geotechnical conditions and applied geotechnical considerations/models, we do, however, have some input. In a tower structure with a garage attached, uneven settlements are always expected and design compensations as well as construction considerations are always provided. This is because the tower’s weight considerably exceeds the garage’s weight.
Most of us at the Construction Advisory Group have worked at the Marquis Tower, a Miami Florida project, for four years, from Preconstruction to Certificate of Occupancy. The Marquis Tower is a 67-story luxury condominium, with an attached garage, structurally similar to The Ocean Tower. As at most buildings located on beaches, the foundation system of The Marquis Tower consists of pile caps supported by friction piles/caissons. It is reasonable to assume that a similar system has been used at the Ocean Tower on South Padre Island.
On projects like this -- and because of expected differential settlements between the two structures -- the garage is built when the tower is close to completion (concrete) thus giving the necessary time for the sinking process to settle and the garage to be built on a more stable geotechnical condition. For example, at Marquis Project, we started erecting the garage when the tower was 40 stories high and when completed, the anticipated garage settlements matched with the respective elevations of the adjacent tower slabs.
Realizing that we do not know the actual field related provisions taken to prevent the Ocean Tower situation, it is a matter of speculation whether the same constructability approach was in use.