METHOD AND SYSTEM FOR RECYCLING CONCRETE MASS IN A SLIPFORM CASTING PROCESS, AND CASTING MACHINE

Abstract

A method for recycling concrete mass in a slipform casting process, where the concrete mass is first cast and compacted with a slipform casting machine comprising a restricted cross-section to form a concrete product to be cast and at least one concrete mass tank for feeding concrete mass to the restricted cross-section, and the cast concrete mass is removed from areas of the fresh cast portion of the concrete product, wherein the removed fresh concrete mass is conveyed and dosed back to the at least one concrete mass tank of the slipform casting machine. The invention also relates to a system and a casting machine for implementing the method.

Claims

1. A method for recycling concrete mass in a slipform casting process, where the concrete mass is first cast and compacted with a slipform casting machine comprising a restricted cross-section to form a concrete product to be cast and at least one concrete mass tank for feeding concrete mass to the restricted cross-section, and the cast concrete mass is removed from areas of the fresh cast portion of the concrete product, wherein the removed fresh concrete mass is moved to a separate receiving bin in the slipform casting machine, from which it is conveyed and dosed back to the at least one concrete mass tank of the slipform casting machine.

2. The method according to claim 1, wherein the removed fresh concrete mass is first transported to a conveyer system, which conveys the removed fresh concrete mass in smaller amounts to the at least one concrete mass tank of the slipform casting machine.

3. The method according to claim 2, wherein the conveyer system comprises a screw conveyer, and the removed fresh concrete mass is transported to one end of the screw conveyer and the screw conveyer doses the removed fresh concrete mass back to the at least one concrete mass tank of the slipform casting machine.

4. The method according to claim 1, wherein small amounts of water is added to the removed fresh concrete mass during its conveying and dosing back to the at least one concrete mass tank of the slipform casting machine.

5. The method according to claim 1, wherein the removal of the concrete mass from the fresh cast portion of the concrete product is implemented with a digging tool of a finishing machine operating on the casting bed.

6. The method according to claim 1, wherein the removal of the concrete mass from the fresh cast portion of the concrete product, and the conveying and dosing of the removed fresh concrete mass back to the at least one mass tank of the slipform casting machine are controlled with an automatic control system.

7. The method according to claim 2, wherein the conveying of the removed fresh concrete mass to the conveyer system and its dosing in smaller amounts to the at least one concrete mass tank is implemented in a time frame, which time frame is shorter than the setting time of the removed concrete mass.

8. A system for recycling concrete mass in a slipform casting process, which system comprises a slipform casting machine with at least one concrete mass tank, and a machine for removing concrete from the cast portion of a fresh slipform cast concrete product, wherein the slipform casting machine comprises a separate receiving bin for the removed concrete mass, to which the machine for removing concrete transport the removed concrete mass, and a conveyer for conveying and dosing the removed concrete mass from the receiving bin to the at least one concrete mass tank.

9. The system according to claim 8, wherein the conveyer is a screw conveyer.

10. The system according to claim 8, wherein the system comprises an automatic control system for controlling the slipform casting machine and the machine for removing concrete.

11. A casting machine for casting concrete products with a substantially horizontal slipform casting, which machine comprises a restricted cross-section defining the product to be cast, and elements for feeding concrete mass to the restricted cross-section comprising at least one concrete mass tank, wherein the machine comprises a separate receiving bin for receiving concrete mass removed from a fresh slipform cast portion of a concrete product, and a conveyer for conveying and dosing the removed concrete mass from the receiving bin to the at least one concrete mass tank.

12. The casting machine according to claim 11, wherein the conveyer is a screw conveyer.

13. The casting machine according to claim 11, wherein the machine comprises devices for adding small amounts of water in the removed concrete mass before it is dosed in the at least one concrete mass tank.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In the following an embodiment of the invention is discussed in greater detail in the sense of example and with reference to accompanying drawings, where

[0024] FIGS. 1A-2B show schematically an embodiment of the invention.

[0025] In the figures is shown an embodiment of the invention, which comprises a slipform casting machine 1 and a finishing machine 2 on a casting bed 3. FIG. 1A shows the machines in normal operational mode as a sideview, and FIG. 1B shows the situation of FIG. 1A as a 3D view. FIG. 2A shows the machines in a concrete mass transfer mode as a sideview, and FIG. 2B shows the situation of FIG. 2A as a 3D view.

DETAILED DESCRIPTION OF THE INVENTION

[0026] The casting machine 1 shown in the embodiment of figures is an extruder-type slipform casting machine comprising a concrete mass tank 5 from which the concrete mass is fed to feed screws inside the casting machine, which feed screws extrude the concrete mass under pressure to a restricted cross-section defining the cross-sectional dimensions of the concrete product to be cast. The compaction effect of the troweling and/or vibrating motion of the surfaces of the restricted cross-section together with the feed pressure of the feed screws compacts the concrete to very dense state, so that the fresh cast concrete product section exiting from the slipform casting machine 1 stays at its form on the casting bed 3 without any other supports. The casting machine 1 proceeds along the casting bed 3 on rails 4 due to the reaction force of the feed screws assisted with additional drive motor of the casting machine, when necessary.

[0027] On ready cast portion of the slipform cast concrete product exiting from the casting machine 1 operates the finishing machine 2, which also moves along the same rails 4 on both side of the casting bed 3. The finishing machine 2 comprises a digging arrangement 6 fixed movably to the frame of the finishing machine with a suitable digging head for digging holes and lead-throughs at predetermined places on the slipform cast fresh concrete product. One known type digging head is disclosed in EP 2 559 531, for example.

[0028] Once the concrete mass is removed from the fresh cast portion of the concrete product with the digging head, the digging arrangement 6 moves the removed concrete mass to a bucket 7, which bucket is connected vertically movably and turnably around horizontal turning axis to the frame of the finishing machine 2.

[0029] Once the bucket 7 is full, or when maximum predefined time has passed from the first removal of concrete mass from the fresh cast portion of the concrete product, or from previous emptying of the bucket, the finishing machine 2 moves next to the slipform casting machine 1 for emptying the bucket 7.

[0030] When the finishing machine 2 has reached the predetermined position in relation to the casting machine 1, the bucket 7 is raised at its maximum height, and turned in relation to its vertical turning axis, as shown in FIGS. 2A and 2B, so that the removed concrete mass collected therein will drop out of the bucket. Since the casting machine 1 continuously slowly proceed with the casting, the finishing machine 2 may also follow the movement of the casting machine during emptying of the bucket 7. Once the bucket 7 is emptied, the finishing machine will return to continue its finishing operations.

[0031] For receiving the collected concrete mass from the bucket 7 of the finishing machine 2, the casting machine 1 is equipped with a receiving bin 8, which receiving bin 8 is located at the longitudinal end area of the casting machine 1 to facilitate this transfer of removed concrete mass from the finishing machine 2 to the casting machine 1.

[0032] At the bottom area of the receiving bin 8 there is an open first end of a screw conveyer 9. The screw conveyer 9 extends from the bottom area of the receiving bin 8 to inside of the upper area of the concrete mass tank 5, where an open second end of the screw conveyer is located.

[0033] Removed concrete mass in the receiving bin 8 drops to the bottom area of the receiving bin and enters to the screw conveyer 9 through its open first end. The screw conveyer 9 conveys and doses the removed concrete mass from the receiving bin 8 to the concrete mass tank 5 of the casting machine 1. The amounts of removed concrete mass to be dosed to the concrete mass inside the concrete mass tank 5 can be controlled by changing the rotating speed of the screw inside the screw conveyer 9.

[0034] The receiving bin 8 and/or the screw conveyer 9 may be equipped with suitable watering arrangement with nozzles for spraying a small amounts of water to removed concrete mass before it is dosed to the concrete mass tank 5 of the casting machine 1.

[0035] Both the casting machine 1 and the finishing machine 2 are advantageously controlled with the same automatic control system 10, or the automatic control systems of these machines are advantageously connected to each other, so that all of the above described actions can be automatized without human interaction.

[0036] In addition to the extruder-type embodiment shown in figures and discussed above, the present invention can be implemented to any slipform casting apparatus comprising at least one concrete mass tank, such as a slipformer-type casting machine for example.

[0037] The specific exemplifying embodiment of the invention shown in figures and discussed above should not be construed as limiting. A person skilled in the art can amend and modify the embodiment in many evident ways within the scope of the attached claims. Thus, the invention is not limited merely to the embodiment described above.