Roadway barrier system with restraining bracket and method of installation

Roadway barrier system which resists lateral movement from roadway forces and thermal transients, accomplished by placing a plurality of restraining brackets along side a plurality of preformed concrete barrier sections. The brackets are anchored to the roadway surface. The barrier system is prevented from moving laterally away from the restraining brackets by enclosing the restraining brackets with channel beams which span the restraining brackets on the side opposite the preformed barrier sections and are secured to the preformed barrier sections with through bolts or studs. This arrangement maintains alignment of the barrier system with plan location yet allows longitudinal thermal expansion and contraction.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to a roadway barrier with restraining system and a method for its installation, and in particular to such a roadway barrier with restraining system and method of installation for resisting lateral movement from roadway vibration forces, temperature changes and vehicular impacts while allowing sufficient longitudinal movement for thermal expansion and contraction.

2. Description of Prior Art

Many roadway barriers in use today are rigid structures installed between opposing lanes of traffic to prevent head-on collisions. Often, they consist of a plurality of preformed sections of reinforced concrete. These sections are positioned in tandem on the roadway by crane or similar device and then secured together, end to end, by means of steel or like channel beams affixed with bolts or studs extending laterally through the preformed concrete sections.

Most barrier systems in use today rely solely on the weight of this system as the means of keeping the barrier in place and correctly aligned. However, these systems incur realignment maintenance costs, because they move in response to thermal expansion and contraction, roadway vibration forces and vehicle impacts.

Identification of Objects of the Invention

The principal object of the invention is to maintain the alignment of existing roadway concrete barrier systems at their plan locations, restricting lateral movement from roadway vibration forces, temperature changes and vehicle impact forces while allowing longitudinal thermal expansion and contraction.

SUMMARY OF THE INVENTION

The present invention is directed to a roadway barrier with restraining system and a method of installation, and particularly to a roadway barrier with restraining system and method of installation for resisting lateral movement from roadway vibration forces, temperature changes and low-energy vehicular impacts while allowing sufficient longitudinal movement for thermal expansion and contraction. Such a barrier maintains alignment in plan location thereby reducing realignment maintenance costs. Furthermore, the present invention augments existing barrier systems commonly in use today, such as the New Jersey type, thereby reducing costs of retrofitting existing barriers and installing new barriers.

The barrier consists of a plurality of preformed sections of reinforced concrete positioned on the roadway in tandem. Preformed barrier sections are fastened together, end to end, with two channel beams at each joint, one on each vertical side of the barrier wall, near the base. In a barrier system without the restraining system of the present invention, the channel beams overlap each preformed barrier section and are affixed to the sections by through bolts or studs. However, with the restraining system of the present invention installed, the channel beams are similarly installed except that shims are inserted laterally between one channel beam and the two barrier sections. That is, the channel beams overlap each preformed barrier section and are affixed to the sections by bolts or studs which pass laterally through the channel beam on one side of the barrier wall, through a shim, through the preformed barrier section, and finally through the other channel beam on the opposite side of the barrier wall. The assembly is secured with washers and nuts as appropriate. The channel beams are typically affixed in this fashion with two bolts or studs passing through each preformed barrier section for a total of four bolts or studs per joint.

The shims form a cavity between the preformed barrier sections and the overlapping channel beam. This thin cavity houses vertical fin of an angular steel restraining bracket of the same thickness, centered longitudinally at the joint between the two preformed barrier sections, put in place prior to securing the channel beam. The horizontal base of this restraining bracket lies parallel and adjacent to the roadway surface, protrudes laterally past the channel beam and contains a slotted hole through which a bolt is anchored into a hole in the roadway using thick asphalt. Thus, the two barrier sections, joined by the channel beams, can slide along the fixed fin of the bracket within their combined cavity. The restraining bracket prevents lateral movement of the barrier, but permits longitudinal motion, the range of which is determined by the length of the bracket and the distance between the innermost edges of the two shims. The restraining brackets are placed at alternate sides of each joint in the barrier wall, if possible, although they may all be placed on one side if required.

A barrier with the restraining system of this invention will maintain alignment in plan location by resisting lateral movement from roadway vibration forces, temperature changes and low-energy vehicular impacts while allowing sufficient longitudinal movement for thermal expansion and contraction. The barrier restraining system of this invention is directly compatible with many existing barrier systems commonly in use today, such as the New Jersey type, thereby reducing costs of retrofitting existing barriers and installing new barriers.

DESCRIPTION OF THE INVENTION

Referring now particularly toFIGS. 1 and 2, the roadway barrier with the restraining system of the present invention is shown schematically in top and front views, respectively. The roadway barrier is indicated generally at11and is secured to the surface of the roadway12. Barrier11is formed of a plurality of preformed barrier sections13A-13D in tandem, coupled with channel beam connectors14A-14F, and secured to roadway12at joints16A-16C between barrier sections13A-13D by restraining brackets15A-15C. Restraining brackets15are placed at alternate sides of each joint16in barrier11if possible, although they may all be placed on one side if required. Two channel beams14span each joint16, one on each vertical side of barrier11. The channel beams14A-14B are fixed to barrier sections13A-13B with two studs17passing through each preformed barrier section13for a total of four bolts or studs per joint16.

Referring now toFIGS. 4,5and6, cross sectional views of barrier11, the channel beams14A and14B are affixed to the barrier section13by studs17which pass through channel beam14A on one side of the barrier wall, through a shim19, through the preformed barrier section13, and finally through the other channel beam14B on the opposite side of barrier11. While the studs17in this design have anchors20and are cast in the preformed barrier sections13, plain studs or bolts may alternatively be used. The assembly is secured with washers21and nuts22as appropriate.

Referring now toFIG. 7, the restraining bracket15is made of one-fourth inch thick galvanized steel or like material and formed into a right angle shape with a vertical fin25and a horizontal base26. Bracket15has a slotted hole23on the horizontal base to accommodate anchor bolt18.

Referring toFIG. 10, shim19is made from polymeric or like material and contains a equal number of slots24as the number of studs17which pass through it. The spacing between the slots24is such as to accommodate the studs17. Shim19is the same thickness as the vertical fin25of restraining bracket15.

Shims19A and19B, positioned laterally between the preformed barrier sections13A and13B and the channel beam14, form a narrow cavity as illustrated inFIG. 8, for placement of the vertical fin25of restraining bracket15centered longitudinally at joint16. The horizontal base26of restraining bracket15lies parallel and adjacent to roadway surface12. The shaft of anchor bolt18passes through slot23in the horizontal base26of bracket15and is set into a hole in the roadway12using thick asphalt. The restraining bracket15and the slotted hole23extend sufficiently outwardly from the channel beam14to allow the anchor bolt18to be installed without interference. The hole in roadway12is drilled to a depth equal to the length and at a diameter one-sixth inch larger than the diameter of anchor bolt18.

The restraining bracket15and anchor bolt18prevent lateral movement of barrier11, but permit longitudinal motion, the range of which is determined by the longitudinal length of the restraining bracket15and the distance between the innermost edges of shims19A and19B.

While preferred embodiments of the present invention have been illustrated in detail, it is apparent that modifications and adaptations of the preferred embodiments will occur to those skilled in the art. It is to be expressly understood that such modifications and adaptations are in the spirit and scope of the present invention as set forth in the following claims.