2025 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS CATEGORY 600 SHOULDERS SECTION 604 — CONCRETE TRAFFIC BARRIERS
604.01 Description
Construct concrete traffic barriers.
604.02 Materials
Crusher Run Aggregate CR-6 901.01 Aggregate 901.01, Size No. 57 Curing Materials 902.07 Form Release Compound 902.08 Portland Cement Concrete 902.10, Mix No. 3 Portland Cement Concrete 902.10, Mix No. 6 or 420.02.04 and 902.10 PVC Pipe Section 905 Reinforcing Steel Section 908, Grade 60, Epoxy Coated Preformed Joint Fillers 911.02 Borrow Excavation 916.01 Geotextile Section 919 Reflective Delineators QPL Fusion Bonded Epoxy 917.02 Use concrete mix No. 6 to construct all concrete traffic barriers, end transitions, and footers unless otherwise specified.
604.03 Construction
Use cast-in-place construction. Excavate to the required depth and to a width that will permit the installation and bracing of forms where necessary. Remove all soft and unsuitable material, and replace it with suitable material. Properly shape the subgrade and compact it as specified in Section 208.
604.03.01 Concrete Barriers. Forming of the footer or concrete barrier may be by either the fixed
form or the slip-form method. Do not construct the footer and the barrier section monolithically.
a.Fixed Form Method. Use steel forms with a tolerance in grade and alignment of 1/4 in. in 10 ft. For bifurcated and transition sections, other forming materials may be used as directed. Thoroughly clean and coat the forms with form release compound each time they are used. Mix and place concrete as specified in 915.03.05 and Section 420, respectively. Vibrate concrete using an approved immersion type mechanical vibrator. Saw or form construction and contraction joints at 20 ft intervals with a minimum of 10 ft. For saw time requirements, refer to 520.03.14(c)(1). Place expansion joints where specified or as directed. Ensure that all joints in footers and walls align. Finish concrete as specified in 604.03.03 except apply a broom finish to the surface when forms are stripped in less than 24 hours. Remove the face forms for finishing as soon as the concrete can retain its shape. After removing the forms, immediately repair all honeycombed and damaged areas.
b.Slip-form Method. Use approved slip-form equipment. The equipment shall have internal vibrating capability and automatic guidance controls to follow line and grade references. On vertical and horizontal curves, set an additional intermediate support in the field to establish an acceptable reference line. Do not use ski or shoe sensors. This method shall not be used within 5 ft of either side of a utility junction box. Use the fixed form method. Mix concrete as specified in 915.03.04. Ensure that the consistency of the concrete after extrusion will maintain the shape of the barrier without support. Provide surfaces that are free of pits larger than 3/16 in. diameter and that require no further finishing other than a broomed finish. Whenever a tear occurs during the operation of the slip-form equipment, repair it immediately or remove and replace as directed. Saw or form construction and contraction joints at 20 ft intervals in the barrier and footer with a minimum of 10 ft, except in the area of miscellaneous structures 6 ft will be permitted. Saw the joints 1/8 in. wide and at least 2 in. deep. Use a diamond blade to saw cut contraction joints in the finished barrier. Make cuts and space joints as specified. Saw cut the contraction joints as soon as possible after initial concrete set and after the concrete has set sufficiently to preclude raveling during the sawing. Complete the sawing the same day the concrete is extruded and before any shrinkage cracking occurs. Do not leave concrete overnight without saw cutting the joints. Place expansion joints as specified or as directed. Terminate slip form placements at a barrier joint. 2025 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS
604.03.02 Curing. Cure and protect concrete as specified in Section 420.
604.03.03 Finished Surface. Finish concrete as specified in Section 420. The completed barriers
shall be within 1/4 in. in 10 ft from the specified horizontal and vertical lines. The barrier shall present a smooth, uniform appearance.
604.03.04 Reflective Delineators. Install reflective delineators on the concrete traffic barrier as
specified.
604.04 Measurement and Payment
The payment will be full compensation for all test panels, excavation, removal of existing asphalt mix, disposal of excess or unsuitable material, reinforcement, drilled holes, drainage appurtenances, geotextile, No. 57 aggregate, conduit, boxes and fittings, backfilling, and for all material, labor, equipment, tools, and incidentals necessary to complete the work. The removal and disposal of unsuitable material will be measured and paid for at the Contract unit price for Class 2 Excavation, which price includes the cost of using suitable excavation as replacement material. When Borrow or Selected Backfill is authorized as replacement material, payment will be made at the Contract unit price for the respective items. The removal of existing concrete traffic barriers will not be measured unless specified elsewhere in the Contract Documents.
604.04.01 Concrete Traffic Barriers will be measured and paid for at the Contract unit price per
linear foot. Measurement will be along the center line of the top of the barrier.
604.04.02 Concrete Traffic Barrier End Transitions will be measured and paid for at the Contract
unit price per each.
604.04.03 Reflective Delineators will be measured and paid for at the Contract unit price per each.
2025 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS 605 — METAL TRAFFIC BARRIERS CATEGORY 600 SHOULDERS SECTION 605 — METAL TRAFFIC BARRIERS
605.01 Description
Furnish and Install metal traffic barriers.
605.01.01 Training and Certifications. The Traffic Barrier W-Beam Manager (TBWBM) shall
have valid certification from successful completion of the Installer option of the “SHA Traffic Barrier Certification.” At all times during the contract, maintain current valid certifications for at least one TBWBM.
605.01.02 Traffic Barrier W-Beam Manager (TBWBM). The Traffic Barrier W-Beam
Manager (TBWBM) is responsible for the appropriate installation of traffic barrier w-beam systems and end treatments, including methods of operation and implementation of corrective actions. Duties include the following
a.Attend pre-construction meeting.
b.Must be present for the entire duration of traffic barrier work to ensure compliance with the Contract Documents and adherence to the manufacturer installation manual for the product being installed.
c.Authorize mobilization of crews to make immediate repairs and implement corrective actions to damaged traffic barrier w-beam and end treatments. In situations where the Engineer determines that public safety is endangered, report for evaluation and determination of work within 24 hours of notification. Coordinate with the Engineer to ensure that all deficiencies are immediately corrected, and that the Contract remains in compliance.
d.When requested, accompany the Engineer during inspections. 2025 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS
Source: Maryland Standard Specifications for Construction and Materials, 2025 Edition. Pages 766–768 of 1,113.