The Park District Project: Top-Down Method minimizes Construction Time
The Park District Project in the center of Dallas includes the construction of a 20 story office building and a 33 story apartment building that will include offices, restaurants and apartments on more than 83,600m².
To minimize construction time, the developer, Trammell Crow Company and their business partner Met Life decided to use the topdown method. This method allowed vertical construction to begin while excavation and development of the needed earth retention system continued below.
The office building includes four levels of below-grade parking. Crews needed to dig nearly 18.3m (60ft) down, hitting a layer of limestone at roughly 6m (20ft) below grade. A precision aligned anchored soldier pile and soil nail temporary retention system with reinforced shotcrete fascia was designed by Orduno Designs Services, LLC to facilitate the construction of this challenging project.
Oscar Orduno, Inc first drilled the anchored soldier piles along the tower’s roughly 91 x 91m (300ft x 300ft) perimeter andinstalled the retention system down to the second basement level. For this purpose, DYWIDAG Soil Nails and DYWIDAG Anchors were drilled in roughly 1.5m (5ft) increments.
Once the above-ground third floor was cast and stressed and the reshoring removed, crews began to excavate the levels below, extending the retention system to basement level 3 and ultimately to basement level 4.
To complete this retention system, DSI supplied approximately 1,000 DYWIDAG Soil Nails consisting of 19mm Ø, Gr 75 THREADBAR® and 200 temporary 46mm Ø, Gr 150, 9-15m (30-50ft) long DYWIDAG Anchors including accessories such as anchor plates.