Precast concrete post tensioned segmented wind turbine tower

Abstract

A post-tensioned precast segmental concrete tower has a stack of annular segments with uniform cross-sections which varies over the tower height. The transition between tower segments occurs in stages and is achieved using annular members or segments which support and anchor post-tensioning tendons that transfer loads passing through the tower as a result of a change in tower geometry. The tower segments are match cast against one another in fabrication to create tight matching opposing surfaces when placed into the tower and to create tight joints. The match casting eliminates the need for grout between precast segments, resulting in a faster tower erection time and high durability of the joints. All annular segments have horizontal joints and no vertical joints. The tower geometry simplifies the formwork system used to precast the segments, and the post-tensioning tendons tie all segments together and to the foundation.

1 - 18 . (canceled) 
     
     
         19 . A precast concrete tower for supporting a wind turbine, comprising:
 a base member positioned to support a tower;   a series of precast concrete annular tower segments supported by the base member forming a vertical stack of the tower segments;   a plurality of anchor members connected to at least one of the annular tower segments and the base member;   a series of vertically extending post tensioning tendons spaced interior to the annular walls of the tower segments connected to the anchor members;   match-cast annular joints between the annular tower segments, the joints comprising:
 a flat annular surface proximate an outer surface of the annular tower segments, and 
 an inclined annular surface contiguous with the flat annular surface forming an obtuse angle with respect to the flat annular surface wherein the inclined annular surface is spaced apart from the outer surface of the annular tower segments. 
   
     
     
         20 . The tower according to  claim 19 , further comprising:
 a plurality of lower tower segments of the annular tower segments having substantially the same horizontal cross-sectional configuration;   a plurality of upper tower segments of the annular tower segments having substantially the same horizontal cross-sectional configuration; and   the upper tower segments being smaller than the lower tower segments in horizontal cross-section.   
     
     
         21 . The tower of  claim 20 , wherein the anchor members engage terminating end portions of the tendons extending from the lower tower segments. 
     
     
         22 . The tower of  claim 19 , wherein the anchor members are integral with the annular tower segments and project from annular walls of the tower segments. 
     
     
         23 . The tower of  claim 19 , wherein an uppermost annular tower segment of the tower segments comprises at least one of the anchor members connected to an upper end portion of the tendons. 
     
     
         24 . The tower of  claim 23 , wherein the uppermost annular tower segment of the tower segments also comprises a connection to a steel tip adapter. 
     
     
         25 . The tower of  claim 19 , wherein the tendons have U-shaped portions extending through the base member. 
     
     
         26 . The tower of  claim 19 , wherein the tendons have L-shape portions extending through the base member; and the tendons have end portions secured to an outer base surface of the base member. 
     
     
         27 . The tower of  claim 19 , wherein at least one of the annular tower segments has flat outer wall surfaces around the tower segments. 
     
     
         28 . The tower of  claim 19 , wherein the vertical stack includes at least five of the annular tower segments of the same diameter. 
     
     
         29 . The tower of  claim 19 , wherein a bottommost precast segment is placed on shims on the base member. 
     
     
         30 . A precast concrete tower for supporting a wind turbine, comprising:
 a base member positioned to support a tower;   a series of precast concrete annular tower segments supported by the base member forming a vertical stack of the tower segments;   a plurality of lower annular tower segments of the annular tower segments having substantially the same horizontal cross-sectional configuration;   a plurality of upper tower segments of the annular tower segments having substantially the same horizontal cross-sectional configuration;   the upper tower segments being smaller than the lower tower segments in horizontal cross-section; and   match-cast annular joints between the annular tower segments, the joints comprising:
 a flat annular surface proximate an outer surface of the annular tower segments; and 
   an inclined annular surface contiguous with the flat annular surface forming an obtuse angle with respect to the flat annular surface wherein the inclined annular surface is spaced apart from the outer surface of the annular tower segments.   
     
     
         31 . The tower of  claim 30 , further comprising:
 precast anchor members incorporated into the tower segments;   a series of vertically extending post tensioning tendons spaced interior to the annular walls of the tower segments connected to the anchor members.   
     
     
         32 . The tower of  claim 32 , wherein an uppermost annular tower segment of the tower segments comprises at least one of the precast anchor members that is connected to upper end portions of the tendons. 
     
     
         33 . The tower of  claim 30 , wherein the tendons have U-shaped portions extending through the base member. 
     
     
         34 . The tower of  claim 30 , wherein the tendons have L-shape portions extending through the base member; and the tendons have end portions secured to an outer base surface of the base member. 
     
     
         35 . The tower of  claim 30 , wherein at least one of the annular tower segments has flat outer wall surfaces around the tower segments. 
     
     
         36 . The tower of  claim 30 , wherein the vertical stack includes at least five of the annular tower segments of the same diameter. 
     
     
         37 . The tower of  claim 30 , wherein the bottommost precast segment is placed on shims on the base member. 
     
     
         38 . A precast concrete tower for supporting a wind turbine, comprising:
 a base member positioned to support a tower;   a series of precast concrete annular tower segments supported by the base member forming a vertical stack of the tower segments;   the vertical stack includes at least five of the annular tower segments of the same diameter;   a plurality of lower annular tower segments of the annular segments having substantially the same horizontal cross-sectional configuration;   a plurality of upper tower segments of the annular segments having substantially the same horizontal cross-sectional configuration;   the upper tower segments being smaller than the lower tower segments in horizontal cross-section;   an uppermost annular tower segment of the tower segments comprises at least one of precast anchor members that is connected to upper end portions of the tendons;   precast anchor members incorporated into the tower segments;   a series of vertically extending post tensioning tendons spaced interior to the annular walls of the tower segments connected to the anchor members; and   match-cast annular joints between the annular tower segments, the joints comprising:
 a flat annular surface proximate an outer surface of the annular tower segments; and 
   an inclined annular surface contiguous with the flat annular surface forming an obtuse angle with respect to the flat annular surface wherein the inclined annular surface is spaced apart from the outer surface of the annular tower segments.