Slip forming structures using multiple molds
View Patent ↗A method of slip forming a concrete structure can include using a first slip form mold that travels along a path to form a portion of a concrete structure by delivering a first flow of concrete into the first mold through a first hopper. The first hopper can be configured to receive the first flow of concrete. The portion of the concrete structure can be modified using a second slip form mold different from the first mold by advancing the second mold along the concrete structure and, while advancing the second mold, delivering a second flow of concrete into the second mold through a second hopper that is configured to receive the second flow of concrete.
1. A method of slip forming a concrete structure, the method comprising:
using a first slip form mold traveling along a path, forming a portion of a concrete structure by delivering a first flow of concrete through a top of the first mold through a first hopper, the first hopper configured to receive the first flow of concrete; and
using a second slip form mold different from the first mold, modifying the portion of the concrete structure by:
advancing the second mold along the concrete structure; and
while advancing the second mold, delivering a second flow of concrete into the second mold through a second hopper configured to receive the second flow of concrete.
2. The method of claim 1 , wherein using the first slip form mold traveling along a path comprises advancing the first slip form mold along a guide, and wherein advancing the second mold along the concrete structure comprises advancing the second slip form machine along the guide.
3. The method of any of claim 1 , wherein advancing the second mold along the concrete structure comprises advancing a top of the second mold at a greater height than a height at which a top of the first mold is advanced.
4. The method of any of claim 1 , wherein the path advanced by the first slip form machine is substantially limited to movement within a horizontal plane.
5. The method of any of claim 1 , wherein forming the portion of the concrete structure comprises advancing the first mold over a structure comprising reinforcing bars.
6. The method of any of claim 1 , wherein the first mold has one or more dimensions different from the second mold.
7. The method of claim 6 , wherein a height of the first mold is greater than a height of the second mold.
8. The method of any of claim 6 , wherein the second mold has a tighter tolerance than the first mold, wherein the tighter tolerance results from being more rigid than the first mold.
9. The method of any of claim 1 , wherein using the first slip form mold traveling along the path comprises disposing the first slip form machine laterally from the portion of a concrete structure relative to a direction of travel of the first slip form machine.
10. The method of any of claim 1 , wherein advancing the second mold along the concrete structure comprises advancing the second mold at a rate of between approximately 0.25 feet/minute and 15 feet/minute.
11. The method of any of claim 1 , wherein delivering the second flow of concrete into the second mold through the second hopper comprises delivering the second flow of concrete nearer a leading end of the second mold than a trailing end of the second mold relative to a direction of travel.
12. The method of any of claim 1 , wherein delivering the first flow of concrete into the first mold through a first hopper comprises delivering a volume of concrete at a rate at least ten times a rate of the second flow of concrete into the second mold through the second hopper.
13. A system for slip molding a concrete structure, the system comprising:
a first slip forming vehicle comprising:
a first hopper;
a first delivery system configured to deliver a first flow of concrete to the first hopper; and
a first slip form mold configured to receive the flow of concrete from the first hopper through a top of the first mold;
a second slip forming vehicle comprising:
a second delivery system configured to deliver a second flow of concrete to the second hopper; and
a second slip form mold configured to receive the second flow of concrete from the second hopper, the second slip form mold spaced from the first slip form mold by a following distance.
14. The system of claim 13 , wherein the second hopper comprises a vibration device configured to vibrate the concrete.
15. The system of any of claim 13 , wherein the following distance is between approximately 10 ft and 150 ft.
16. The system of any of claim 13 , wherein the following distance is between approximately 1.5 minutes and 90 minutes.
17. The system of any of claim 13 , wherein the first slip form mold has a height greater than a height of the second slip form mold.
18. The system of any of claim 13 , wherein the first slip form mold has a length along a direction of travel greater than a length of the second slip form mold.
19. The system of any of claim 13 , wherein the second hopper is disposed nearer a leading end of the second slip form mold than a trailing end of the second slip form mold in relation to a direction of travel.
20. The system of any of claim 13 , wherein the second slip forming vehicle further comprises a clearance indicator disposed between the first slip form mold and the second slip form mold.