Stone Columns

发布网友发布时间：2022-05-02 20:28

共1个回答

热心网友时间：2022-06-26 21:51

A method nowbeing used to increase the load-bearing capacity of shallowfoundations on soft clay layers is the construction of stone columns. Construction of a stone column generally consists of water-jetting a vibroflot into the soft clay layer to make a circular hole that extends through the clay to firmer soil. The hole is then filled with an imported gravel. The gravel in the hole is graally compacted as the vibrator is withdrawn. The gravel used for the stone column has sizes ranging from 0. 25 － 1. 5in ( 6 － 40 mm ) . Stone columns usually have diameters of 1. 6 － 2. 5 ft ( 0. 5 － 0. 75 m ) and are spaced at about 5 － 10 ft ( 1. 5 － 3 m ) center-to-center. After the construction of stone columns，a fill material should always be placed over the ground surface and compacted before construction of the foundation. The stone columns tend to rece the settlement of foundations at allowable loads.

Stone columns work more effectively when used for stabilizing a large area where the undrained shear strength of the subsoil is in the range of 10 － 15 kN / m2than does improving the bearing capacity of structural foundations. Subsoils are weaker than that may not provide sufficient lateral support for the stone columns. For large-site improvement，stone columns are most effective to a depth of 20 － 30 ft ( 6 － 10 m ) . However，stone columns have been constructed to a depth of 100 ft ( 31 m) .