Not Applicable
The various embodiments and aspects disclosed herein relate to apparatuses and methods for limiting movement between adjacent concrete structures.
In dealing with concrete, cold joints are typically formed between two or more poured concrete slabs. These cold joints may become uneven or buckle due to normal thermal expansion and contraction of the concrete and/or compaction of the underlying flow ground by inadequate substrate preparation prior to pouring of the concrete. In order to mitigate these negative effects, slip dowel systems are typically used to join adjacent concrete slabs that limit vertical movement. However, these systems have various deficiencies.
Accordingly, there is a need in the art for an improved slip dowel system.
The various embodiments and aspects described herein address the deficiencies described above, described below and those that are known in the art.
A slip dowel system is described herein which allows two adjacent concrete slabs to move closer to or further away from each other as well as side to side but limits relative vertical movement therebetween. In particular, the system has a receiving member comprised of an enlarged sheath. The sheath houses a main tube. The enlarged sheath and the main tube are embedded within one of two adjacent slabs. The enlarged sheath allows the main tube to move transversely within the sheath. An elongate dowel is inserted within the main tube and allowed to freely move into and further out of the main tube. A first end portion of the elongate tube is slidably disposed within the main tube. An opposed second end portion of the elongate tube is fixedly embedded within the other slab. When the first and second slabs move away or closer to each other, the first end portion of the elongate dowel slides within the main tube. When the first and second slabs move transversely with respect to each other, the main tube slides within the sheath to permit such transverse movement between the first and second slabs. Crushed tubes may be disposed within the sheath beside the main tube to provide strength to the sheath and for other purposes.
More particularly, a concrete dowel system for limiting vertical movement between adjacent first and second concrete structures and permitting longitudinal and traverse horizontal movement between the adjacent first and second concrete structures is disclosed. The system may comprise a base member, a dowel receiving sheath, left and right crush tubes and an outer sheath. The base member may be attached to a form which forms the first concrete structure. The dowel receiving sheath may have an inner lumen defining a longitudinal axis. The dowel receiving sheath may be attached to the base member so that the longitudinal axis of the inner lumen of the dowel receiving sheath is perpendicular to a vertical edge surface of the form. Left and right crush tubes may be laterally disposed adjacent to left and right sides of the dowel receiving sheath when the base member and the dowel receiving sheath are attached to the vertical edge surface of the form. The outer sheath may cover the dowel receiving sheath and the left and right crush tubes. The outer sheath forms void(s) on the left and right lateral sides of the dowel receiving sheath to allow for transverse horizontal movement with respect to the longitudinal axis between the adjacent first and second concrete structures.
The dowel receiving sheath may be slidably traversable laterally left and right within the outer sheath upon crushing of the left and right crush tubes by a dowel. The left and right crush tubes may have a wall thickness less than a wall thickness of the dowel receiving sheath for allowing the left and right crush tubes to collapse when pressure is applied by the dowel receiving sheath upon lateral movement of the adjacent first and second structures.
The outer sheath, crush tubes and the dowel receiving sheath may be formed as an extruded part.
The inner lumen of the dowel receiving sheath may be circular, square or polygonal.
The outer sheath may have an interior oval cross sectional configuration and the dowel receiving sheath may have an exterior circular cross sectional configuration.
In another aspect, a method of forming adjacent first and second concrete structures that have a limited vertical movement between adjacent first and second concrete structures and permit longitudinal and traverse horizontal movement between the adjacent first and second concrete structures is disclosed. The method may comprise the steps of building a first concrete form; attaching a base member and a dowel receiving sheath to a vertical edge surface of the first concrete form with a longitudinal axis of an inner lumen of the dowel receiving sheath oriented perpendicular to the vertical edge surface of the first concrete form; pouring concrete into the first concrete form and allowing the concrete to set which defines the first concrete structure; forming voids on left and right lateral sides of the dowel receiving sheath to allow for transverse horizontal movement with respect to the longitudinal axis between the adjacent first and second concrete structures; removing the first concrete form and the base member from the first concrete structure; sliding a dowel into the inner lumen of the dowel receiving sheath; building a second concrete form adjacent to the first concrete structure; and pouring concrete into the second concrete form and allowing the concrete to set which defines the second concrete structure.
In the method, the attaching step may include the step of disposing the base member and the dowel receiving sheath on opposed sides of the first concrete form. The attaching step may further include the step of forming a hole within the first concrete form, inserting a distal portion of the base member through the hole of the first concrete form and securing the dowel receiving sheath to the distal portion of the base member.
These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which:
Referring now to the drawings, a slip dowel system 10 that provides for longitudinal movement 12 and transverse movement 14 between two adjacent concrete slabs 16, 18 is shown. The slip dowel system 10 has a dowel 20 that is embedded in the first slab 16 and slidably embedded within the second slab 18. In particular, the dowel 20 extends out of the first slab 16 and into a main tube 22 embedded within the second slab 18. The first and second slabs 16 and 18 can move in the longitudinal direction 12 since the dowel 20 slides in and out of the main tube 22. Lateral crush tubes 24 are disposed adjacent to the main tube 22 to centrally locate the main tube 22 within a sheath 26. When the first and second slabs 16, 18 move transversely 14 with respect to each other, the main tube 22 crushes the crush tubes 24 to make room for the main tube 22 within the sheath 26 and also to allow for transverse movement between the two slabs 16, 18. In this manner, the first and second slabs 16, 18 are able to move longitudinally 12 and transversely 14 with respect to each other. However, the edges 28, 30 of the first and second slabs 16, 18 are limited in its vertical movement in the Z direction.
Referring now to
A base plate 38 may be used to hold the receiving member 32 in position as the uncured concrete 44 is being poured into the form 34. The base plate 38 has a base member 40 and a distal portion 42. The distal portion 42 is inserted through the through hole 36 and extends out into the interior of the concrete form 34, as shown in
After the receiving member 32 is mounted to the base plate 38, uncured concrete 44 may be poured into the concrete form 34 and allowed to cure over time, as shown in
Referring now to
The lateral crush tubes 24 may have a thickness 58 sufficient to hold the main tube 22 in place but also be capable of being deformed as shown in
The sheath 26 may have a thickness 60 which is sufficient to withstand the weight of the concrete 44 so that a void 62 is maintained within the sheath 26 to allow for transverse movement of the main tube 22 within the sheath 26.
The crush tubes 24 of the receiving member 32a shown in
Referring further still to
Referring now to
The slip dowel system was discussed in relation to two concrete slabs. However, the slip dowel system may be used or incorporated into other adjacent structures that require lateral and horizontal movement but not vertical movement. Other structures include and are not limited to concrete walls, wooden structures and other structures made from other materials.
The above description is given by way of example, and not limitation. Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed herein, including various ways of arranging the sheath crush tube and main tube. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments.
This is a continuation patent application of U.S. patent application Ser. No. 14/540,288 filed Nov. 13, 2014, the entirety of which is expressly incorporated herein by reference.
Number | Date | Country | |
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Parent | 14540288 | Nov 2014 | US |
Child | 15098157 | US |