Pile mandrel with extendable reaming members

Abstract

A set of one or more reaming members is secured to a pile mandrel. Each reaming member is moveable between a first position where the reaming member extends a first distance from a center of the pile mandrel, and a second position where the reaming member extends a second distance from the center of the pile mandrel. An apparatus including a pile mandrel and one or more reaming members attached to the mandrel is driven into soil, creating a hole extending down from a surface of the soil. While the reaming member(s) are below the surface of the soil, the reaming member(s) are extended to an extended position; the pile mandrel is rotated with the reaming member(s) extended to ream a section of the hole to a second diameter that is larger than the first diameter; the reaming member(s) are retracted, and the mandrel is removed from the hole.

1 . An apparatus comprising:
 a pile mandrel that is adapted to be driven into soil by a pile hammer, the pile mandrel defining:
 a top opening located near a top end of the pile mandrel, the top opening being positioned to receive grout to be fed through the pile mandrel; and 
 a bottom opening located near a bottom end of the pile mandrel, the bottom opening being positioned to pass grout from the pile mandrel; and 
   a set of one or more reaming members secured to the pile mandrel, each of the one or more reaming members being moveable between a first position where the reaming member extends a first distance from a center of the pile mandrel, and a second position where the reaming member extends a second distance from the center of the pile mandrel, the second distance being different from the first distance.   
   
   
       2 . The apparatus of  claim 1 , wherein each of the one or more reaming members comprises a curved bar. 
   
   
       3 . The apparatus of  claim 1 , wherein each of the one or more reaming members is pivotally connected to the pile mandrel. 
   
   
       4 . The apparatus of  claim 1 , wherein, when the pile mandrel has been driven into soil, interaction between the one or more reaming members and the soil can bias each of the one or more reaming members between the first and second positions. 
   
   
       5 . The apparatus of  claim 1 , wherein, when the pile mandrel has been driven into soil, rotating the pile mandrel in a first direction biases each of the one or more reaming members toward the first position. 
   
   
       6 . The apparatus of  claim 1 , wherein, when the pile mandrel has been driven into soil, rotating the pile mandrel in a first direction biases each of the one or more reaming members toward the first position, and rotating the pile mandrel in an opposite second direction biases each of the one or more reaming members toward the second position. 
   
   
       7 . The apparatus of  claim 1 , wherein the set of one or more reaming members comprises multiple reaming members. 
   
   
       8 . The apparatus of  claim 1 , wherein the set of one or more reaming members comprises multiple rows of reaming members. 
   
   
       9 . An apparatus comprising:
 a pile mandrel;   a set of one or more reaming members mounted on the pile mandrel, each of the one or more reaming members being moveable between a first position where the reaming member extends to a first radius from a center of the pile mandrel and a second position where the reaming member extends to a second radius from the center of the pile mandrel, the second radius being different from the first radius;   a hammer that is adapted to drive the pile mandrel into soil; and   a drill that is adapted to rotate the pile mandrel while the pile mandrel is at least partially in the soil;   wherein rotation of the pile mandrel while the one or more reaming members are in the soil biases the one or more reaming members between the first and second positions.   
   
   
       10 . The apparatus of  claim 9 , wherein:
 rotation of the pile mandrel in a first direction while the one or more reaming members are in the soil causes the one or more reaming members to engage the soil to bias the one or more reaming members toward the first position; and   rotation of the pile mandrel in a second direction, which is opposite to the first direction, while the one or more reaming members are in the soil causes the one or more reaming members to engage the soil to bias the one or more reaming members toward the second position.   
   
   
       11 . The apparatus of  claim 9 , wherein the drill is adapted to engage the pile mandrel to lift the pile mandrel while the pile mandrel is at least partially in the soil. 
   
   
       12 . The apparatus of  claim 11 , wherein the drill is adapted to simultaneously rotate and lift the pile mandrel while the pile mandrel is at least partially in the soil. 
   
   
       13 . The apparatus of  claim 9 , wherein each of the one or more reaming members is able to pivot between the first position and the second position. 
   
   
       14 . The apparatus of  claim 9 , wherein the drill and the hammer are secured to a single support structure. 
   
   
       15 . A method comprising:
 driving an apparatus into soil, the apparatus including a pile mandrel and one or more reaming members attached to the mandrel, wherein driving the apparatus into soil includes displacing the soil outwardly and downwardly from the pile mandrel, creating a hole extending down from a surface of the soil, the hole having a first diameter;   while the one or more reaming members attached to the pile mandrel are below the surface of the soil:
 extending the one or more reaming members from a retracted position to an extended position; 
 rotating the pile mandrel with the one or more reaming members in the extended position to ream a section of the hole to a second diameter that is larger than the first diameter; and 
 retracting the one or more reaming members from the extended position; 
   removing the pile mandrel from the soil;   filling the hole with a substantially liquid material; and   allowing the substantially liquid material to solidify.   
   
   
       16 . The method of  claim 15 , wherein extending the one or more reaming members comprises rotating the pile mandrel in a first direction. 
   
   
       17 . The method of  claim 16 , wherein extending the one or more reaming members comprises engaging the soil with the one or more reaming members. 
   
   
       18 . The method of  claim 16 , wherein retracting the one or more reaming members comprises rotating the pile mandrel in a second direction. 
   
   
       19 . The method of  claim 18 , wherein retracting the one or more reaming members comprises engaging the soil with the one or more reaming members. 
   
   
       20 . The method of  claim 15 , further comprising lifting the pile mandrel while rotating the pile mandrel with the one or more reaming members in the extended position.