Continuous strand hoop reinforcement for concrete foundations

Abstract

A post-tensioned continuous strand hoop reinforcement for concrete foundations is provided. The post-tensioned continuous strand hoop reinforcement compresses the concrete to prevent cracking and significantly reduces foundation deflection and distortion which increases rotational stiffness in anchor caps, spread foundations, and like foundation configurations.

What is claimed is: 
     
         1 . A concrete foundation for supporting dynamic tall, heavy, and/or large structures including towers and/or poles which can be precast or constructed in-situ comprising:
 a substantially annular concrete base embedded in a support surface;   a plurality of tower anchor bolts in spaced relationship arranged as a ring around a center of said foundation, said tower anchor bolts being embedded in said concrete base; and   a continuous strand reinforcing hoop spirally wound around the center of said foundation.   
     
     
         2 . The foundation as set forth in  claim 1 , wherein the continuous strand reinforcing hoop extends from near a bottom of said embedded concrete base upwardly above a top of said concrete base. 
     
     
         3 . The foundation as set forth in  claim 2 , wherein the continuous strand reinforcing hoop forms a plurality of windings as said hoop extends from near a bottom of said embedded concrete base upwardly above a top of said concrete base, said windings being spaced from one another by about six inches. 
     
     
         4 . The foundation as set forth in  claim 1 , wherein the continuous strand reinforcing hoop is post-tensioned. 
     
     
         5 . The foundation as set forth in  claim 1 , wherein the continuous strand reinforcing hoop includes an inner continuous strand reinforcing hoop and an outer continuous strand reinforcing hoop. 
     
     
         6 . The foundation as set forth in  claim 5 , wherein the inner continuous strand reinforcing hoop is spirally wound upwardly from near a bottom of said foundation and around the ring of tower anchor bolts. 
     
     
         7 . The foundation as set forth in  claim 5 , wherein said plurality of tower anchor bolts includes an inner ring of tower anchor bolts and an outer ring of tower anchor bolts, the inner continuous strand reinforcing hoop being spirally wound upwardly from near a bottom of said foundation and around the ring of inner tower anchor bolts and the outer continuous strand reinforcing hoop being spirally wound upwardly from near a bottom of said foundation and around the ring of outer tower anchor bolts. 
     
     
         8 . The foundation as set forth in  claim 1 , wherein said continuous strand reinforcing hoop prevents separation of horizontal (lateral) reinforcing and/or splitting of concrete circumferentially between vertical and horizontal (lateral) reinforcing with continuous strand hoop reinforcement. 
     
     
         9 . The foundation as set forth in  claim 1 , wherein the continuous strand reinforcing hoop is a continuous steel strand or cable inside a rubber coating or like flexible sleeve to prevent concrete bonding to the strand or cable to allow the strand or cable to be pulled, elongated and post-tensioned. 
     
     
         10 . The foundation as set forth in  claim 1 , wherein the continuous strand reinforcing hoop is made of high strength steel which requires up to less than half the steel weight, volume, and length as conventional rebar hoops. 
     
     
         11 . A covered continuous steel strand or cable which can be post-tensioned and elongated and secured against concrete or a steel base plate of a foundation with a wedged nut like apparatus near the ends of the strand or cable. 
     
     
         12 . A post-tensioned continuous strand hoop reinforcement for concrete foundations, said post-tensioned continuous strand hoop reinforcement compressing the concrete to prevent cracking and significantly reducing foundation deflection and distortion which increases rotational stiffness in anchor caps, spread foundations, and like foundation configurations. 
     
     
         13 . The post-tensioned continuous strand hoop reinforcement as set forth in  claim 12 , wherein the continuous strand reinforcement is a continuous strand hoop made of a continuous steel strand or cable inside a rubber coating or like flexible sleeve to prevent concrete bonding to the strand or cable to allow the strand or cable to be pulled, elongated and post-tensioned. 
     
     
         14 . The post-tensioned continuous strand hoop reinforcement as set forth in  claim 13 , wherein the continuous strand reinforcing hoop is made of high strength steel which requires up to less than half the steel weight, volume, and length as conventional rebar hoops. 
     
     
         15 . A method of constructing a pile anchor foundation in-situ comprising the steps of:
 excavating for a concrete foundation cap;   installing a plurality of pile anchors;   installing a plurality of tower anchor bolts with an embedment ring near a bottom of the foundation cap;   installing coiled strand hoop guides at intervals between horizontal steel and wire tying continuous strand reinforcing hoops in the coiled strand hoop guides;   monolithically pouring the concrete foundation cap and, once the concrete has sufficiently cured and set, post-tensioning the pile anchors and the continuous strand reinforcing hoops.