625.1General Description
This work includes furnishing and installing a visual barrier according to this specification and conforming to the locations, dimensions, lines, and grades shown on the plans. Unless a specific type is required by the Contract documents, select one of the following barrier types. Type B Interlock steel panels Type C Precast concrete panels Type D Treated timber panels Type F Glass reinforced thermoset composite structural panels Type G Precast autoclaved aerated concrete (PAAC) panels 625.1.1 Definitions General Provisions 101 through 150. 625.1.2 Related References
GDT 7 GDT 20 GDT 21 GDT 24a GDT 24b GDT 59 GDT 67 QPL 42 QPL 53 QPL 90 1034 1034 1034 1034 1034
Federal Specification QQ-S-763-C AASHTO ASTM M 31/M 31M M 32/M 32M M 111/M 111M M 270/M 270M A 153/153M A 366 A 526 A 568 A 569 A 572 A 591 A 653/653M A 792/792M B 695 B 766 C 1693 D 638 D 695 D 790 D 792 D 2092 D 2583 E 90 G 154 625.1.3 Submittals Submit Shop Drawings to the Engineer for review and approval. Prepare Shop Drawings for each Visual Barrier. Show all details necessary for field erection. The minimum requirements are: • Complete elevation view showing the top and bottom elevations, the required wall envelope, the roadway grade and ground line at the barrier. • Diameter and depth of caissons at each post • Post size • Complete plan view with dimensions, stations and offset Have the manufacturer certify to the Department that a specimen of the proposed barrier meets or exceeds a minimum weighted Visual transmission loss of 20 dBA. Furnish test results for barrier material types (except Type C). The transmission or loss results must be based on the generalized truck spectrum when tested according to ASTM E 90.
625.2Materials
Ensure that other materials not listed herein meet the requirements of the appropriate specification to which they pertain.
Concrete-Class A Hollow Load Bearing Concrete Masonry Units (Concrete Block) ASTM C 90, Grade N-I or N-II Mortar Section 834
Use cold formed configured steel panels that meet these requirements:
Class 2 with a minimum thickness of 0.029 in. (0.74 mm)
adequately according to the manufacturer’s specifications
when connected to another panel and held in a vertical or horizontal position
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AZ50 (AZM150) weight of 55% aluminum-zinc alloy according to ASTM A 792/792M.
Use one of the following coatings:
1) Apply the coating system (including primer) at a total minimum film thickness of 1 mil (0.03 mm) per coated side. 2) Cure the polyvinylidene fluoride film to at least 0.8 mil (0.02 mm) film thickness.
(0.04 mm) coated on both sides. 1) Have the coating applied at the factory to thoroughly cleaned and pretreated galvanized steel according to ASTM D 2092, Method F. 2) Laminate the coating to the galvanized steel using heat and adhesive to form a uniform and durable coating pigmented to obtain optimum color performance. 3) Use a color from the Federal Standard Color Number indicated on the plans. Ensure that caulking is color pigmented to match the barrier color specified.
Use post for steel barriers with these features:
111/M 111M.
affixed near one end of each post.
Use flashing and caps for steel barriers that are the same material and color coating as the panels. Fasten steel flashing and caps with self-tapping screws. Ensure that A-1 screws are Class #410 Stainless Steel and conform to Federal Specification QQ-S-763-C, or are cadmium coated according to ASTM B 766.
Attach panels to posts using a powder-actuated fastening system. Fasteners shall be stainless steel or shall be hot-dip galvanized as per ASTM A 153 Class C or shall have a mechanically deposited zinc coating as per ASTM B 695 Class 50.
Class AA Concrete or SCC Concrete Section 500 Reinforcing AASHTO M 31/M 31M and M 32/M 32M Piling-Galvanized Steel Section 520 and AASHTO M 111/M 111M Elastomeric Bearing Pads Section 885 If SCC is used the following shall be met: wet/cement ratio 0.40 min 3500 psi Spread Slump 24” ± 2”, Air Entrainment – min 3.5% to max 6.5%
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Use treated timber panels that meet these requirements: Noise Barrier Walls See QPL 90 Class A Concrete Section 500 Lumber and Timber Section 860 Preservative Treatment of Timber Products Section 863
PROPERTY MINIMUM VALUE TEST METHOD Flexural Modulus 2,200,000 psi (15200 MPa) ASTM D 790 Flexural Strength 70,000 psi (480 MPa) ASTM D 790 Tensile Strength 65,000 psi (450 MPa) ASTM D 638 Tensile Modulus 4,500,000 psi (31000 MPa) ASTM D 638 Elongation 1.5% ASTM D 638 Compressive Strength 60,000 psi (410 MPa) ASTM D 695 Barcol Hardness 50 ASTM D 2583 Specific Gravity 1.86 ASTM D 792
sorted and graded ground tire rubber (0.25 + 0.025 inch (6.4 + 0.6 mm)).
and hot dip galvanized in accordance with AASHTO M 111/M 111M, except coating weight shall be a minimum of 2.0 oz/ft. 2 (600 g/m2) on all sides.
which they pertain. 1037 1037 1037 1037 1037
Portland cement, fine aggregate, water, gypsum, lime, and an expansion agent. After setting, and before hardening, the PAAC is machine cut to the required size, then steam-cured under pressure in an autoclave. Use PAAC that meets the following physical requirements:
in accordance with ASTM C 1693, with no single specimen having a compressive strength of less than 580 psi (4000 kPa).
accordance with ASTM C 1693
same topcoat color on both the PAAC panels and the steel supports. Submit independent laboratory test results for 1500 hours of accelerated weathering in accordance with ASTM G 154. Submit results that show ratings of at least 9 in the following categories: color change, chalking, checking, cracking, blistering, flaking and rusting. Submit a certification stating that the PAAC topcoat is graffiti resistant.
ASTM A-569 and ASTM A-568.
quality, Complying with ASTM A526, with ASTM A653, G-60 zinc coating, mill phosphatized. Use for all exterior units.
into exterior barriers, complying with ASTM A-153, Class C or D as applicable.
Use one of the following coatings:
1) Apply the coating system (including primer) at a total minimum film thickness of 1 mil (0.03 mm) per coated side. 2) Cure the polyvinylidene fluoride film to at least 0.8 mil (0.02 mm) film thickness.
(0.04 mm) coated on both sides. 1) Have the coating applied at the factory to thoroughly cleaned and pretreated galvanized steel according to ASTM D 2092, Method F. 2) Laminate the coating to the galvanized steel using heat and adhesive to form a uniform and durable coating pigmented to obtain optimum color performance. 3) Use a color from the Federal Standard Color Number indicated on the plans. 1038 1038 1038 1038 1038
625.2.01 Delivery, Storage, and Handling General Provisions 101 through 150.
625.3Construction Requirements
625.3.1 Personnel General Provisions 101 through 150. 625.3.2 Equipment General Provisions 101 through 150. 625.3.3 Preparation General Provisions 101 through 150. 625.3.4 Fabrication General Provisions 101 through 150. 625.3.5 Construction Perform the following work according to the specifications:
When necessary, clear and grub according to Section 201 as applicable.
Perform excavation, borrow, and embankment according to Section 205,
Section 206, Section 208, or Section 210. The scope and dimensions of the work are shown on the plans.
Perform grassing according to Section 700, as specified on the plans.
Plant vine, shrub, and trees according to Section 702 as specified on the plans.
When items are shown on the plans but are not covered in this specification, the plans and Standard
specifications govern the work.
Follow these requirements to construct each type of barrier:
Install steel visual barrier according to the manufacturer’s recommendations and plan details. Repair cut,
scratched, or marred surfaces according to the manufacturer’s recommendations.
When using precast concrete panels:
cured the same as the panels, and from inspection during manufacture.
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by hand tamping and rodding to force the concrete into the corners of the forms to eliminate stone
pockets, cleavage planes, and air bubbles.
barrier, provide a similar finish to the opposite side unless noted otherwise in the plans.
(wet cure) long enough for the concrete to develop the specified compressive strength.
1) Ensure that the curing period is at least 72 hours under normal summer temperature conditions. In
colder weather extend the curing period, as directed by the Engineer
2) Protect the panels from freezing from the time the concrete is placed until curing is complete.
3) Instead of the wet cure method, steam cure the panels as specified in Subsection 865.2.01.B.2.g.(2) if
desired.
NOTE: Even with the Inspector’s acceptance at the precast yard, panels can still be rejected at the
erection point if they are damaged.
Place bearing pads as shown in the plans and tighten the restraining bolts.
dirt or stains.
identified in the plans. In these areas, the concrete panels will be constructed with special form liners
based on the attached renderings.
The Plans shall designate the correct type of D barrier (Type D.1 or Type D.2.).
Construct this barrier of tongue and groove panels placed in a horizontal configuration supported by
vertical posts set on concrete piers. Follow the plan details for information on sizes, timber treatment, and
erection.
Construct this barrier of double wood panels staggered to provide a 1/2-width overlap. The supports are
posts set in a concrete footing. Follow the plans for full details of materials and erection, sizes, and
timber treatment.
Install in accordance with manufacturer’s recommendations and plan details. Do not install barriers with
burns, discolorations, cracks, or other objectionable marks that would adversely affect the performance of
the system.
cured the same as the panels, and from inspection during manufacture.
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side of the barrier, provide a similar finish to the opposite side unless noted otherwise in the plans.
by hand tamping and rodding to force the concrete into the corners of the forms to eliminate stone
pockets, cleavage planes, and air bubbles.
that the units meet the physical requirements of Subsection 625.2.G.1.
NOTE: Even with the Inspector’s acceptance at the precast yard, panels can still be rejected at the
erection point if they are damaged.
dirt or stains.
1) PAAC panels. Apply the coating with a sponge-textured roller in accordance with the manufacturer’s
recommendations. Cover all exposed galvanized steel surfaces for protection from splattering. Apply
the coating at a minimum thickness of 60 dry mils (1.5 mm). Apply the coating only when the ambient
temperature is greater than 40 o F (4 o C) and rising. Do not apply any coating during rainfall or when
rainfall is forecast overnight.
2) Galvanized Steel Supports. Apply a corrosion resistant coating by brush, roller, or airless spray in
accordance with the manufacturer’s recommendations. Protect the adjacent PAAC surfaces from
overspray. Apply the coating at a minimum thickness of 2 dry mils (0.5 mm). Use a color that matches
the PAAC final topcoat color. Apply the coating only when the ambient temperature and relative
humidity fall within the limits stated by the manufacturer.
Before beginning earthwork on the Project, stake the visual barriers in the field and establish the final ground
line elevations at the barrier.
Furnish these elevations to the supplier who will develop the shop plans, including a complete elevation view
of each barrier indicating top and bottom elevations and the roadway grade.
them without the Engineer’s approval.
metal barriers is not a secondary source of noise transmission.
recommendations and as directed by the Engineer at the Contractor’s expense.
• Submit load calculations for the specific connection to be modified.
• Use a safety factor of at least 3.0.
If the Engineer believes the trench is too narrow for compaction, backfill the trench excavation
with concrete grout to the Engineer’s satisfaction. No additional compensation will be made for the
concrete grout.
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as the Engineer deems practical.
plant grass or sod.
1) Vertical alignment for barriers and posts is:
2) Horizontal alignment for barriers is close to that shown on roadway plans.
3) Post spacings are within 0.5 in. (15 mm) of their intended location.
to 95% of the maximum density as determined by GDT 7, GDT 24a, GDT 24b or GDT 67, as applicable.
Determine in-place density according to GDT 20, GDT 21, or GDT 59, as applicable.
This work includes providing graffiti-proof coating on both faces of concrete and masonry barriers from the
ground line to the top of the barrier.
intact. Store the materials out of the weather, in a single location, and as specified by the manufacturer.
could cause.
Use application equipment recommended or approved by the coating manufacturer for use on this
project. Use equipment in good operating condition.
by the coating manufacturer.
low-pressure spray.
625.3.6 Quality Acceptance
The panels are subject to rejection if they fail to meet the requirements specified above. The following defects are also
cause for rejection for Barrier Type C and G:
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625.3.7 Contractor Warranty and Maintenance
General Provisions 101 through 150.
625.4Measurement
Clearing and grubbing will not be measured separately for payment.
Excavation, borrow, and embankment are measured according to Section 205, Section 206, Section 208, or
Section 210, as applicable.
The scope and dimensions of the work are as shown on the plans.
Grassing is not measured separately for payment unless shown on the Plans as a payment item. In this case, the
work is measured according to the requirements of Section 700 for the type of grassing required.
Vine, shrub, and tree planting shown on the Plans is measured according to Section 702.
Items shown on the plans but not covered in this Specification are measured for payment according to the
applicable portions of the specifications.
Steel barrier is measured in square feet (meters) of barrier surface installed before backfilling complete in
place according to Subsection 109.01, Measurement and Quantities. Posts, flashing, caps, concrete post
embedment, or other incidental items required for construction are not measured separately.
Precast concrete Visual barriers are measured in square feet (meters) of barrier surface before backfilling,
including pile flanges, complete in place and accepted.
No separate measurement is made for pile, anchor bolts, plates, connections, neoprene bearing pads,
connecting bolts, or other Visual barrier components.
Treated timber barriers are measured in square feet (meters) of barrier surface installed before backfilling.
No separate measurement is made for posts, caps, foundations, footings, hardware, timber treatment, pile, or
cover boards.
Glass reinforced thermoset composite structural panel barriers are measured in square feet (meters) of barrier
surface installed before backfilling.
No separate measurement is made for posts, top caps, bottom caps, side caps, flashing, strip seals,
mounting brackets and hardware, concrete post embedment, or other incidental items required for
construction.
Precast autoclaved aerated concrete barriers are measured in square feet (meters) of barrier surface installed
before backfilling.
No separate measurement is made for steel supports or other incidental items required for construction. 10431043104310431043
Only authorized changes required to adjust plan ground elevations and other authorized changes will be
measured. Payment will be made based on plan quantity unless changes are authorized.
625.4.01 Limits
General Provisions 101 through 150.
625.5Payment
The cost of clearing and grubbing is included in the Lump Sum Item for the project. When clearing and grubbing is not
shown as a payment Item, the cost is included in the overall Contract Price for the work covered in this specification.
Unclassified excavation and borrow will be paid for and included in the normal excavation and borrow for the
Project unless shown on the plans as a separate payment Item for Visual barriers. In that case, payment will be
made under Section 205, Section 206, Section 208, or Section 210, as applicable.
Grassing will be paid for and is included in the normal grassing for the project according to Section 700 unless
shown on the plans to be included in the price bid for Visual barriers.
Items shown on the Plans to be paid for but are not covered by this specification will be paid for according to the
applicable portions of the specifications.
Unless a specific barrier type is specified in the Contract, identify in the proposal which barrier type will be used.
Steel barrier will be paid for at the Contract Unit Price bid per square foot (meter). Payment is full
compensation for furnishing and installing materials, providing post and post embedment, and providing
labor, equipment, and incidentals to complete the Work.
Precast concrete Visual barrier will be paid for at the Contract Unit Price bid per square foot (meter). Payment
is full compensation for furnishing materials, including piling and attachments and for erecting the Visual
barrier, including graffiti-proof coating.
No separate measurement is made for special barrier construction. Contract price shall include construction
of the special barrier in the pay item below.
Treated timber barrier will be paid for at the Contract Unit Price bid per square foot (meter). Payment is full
compensation for furnishing materials including concrete and steel and for erecting the Visual barrier.
Glass reinforced thermoset panel barriers will be paid for at the Contract Unit Price bid per square foot
(meter). Payment is full compensation for furnishing and installing materials, including post and post
embedment, and for erecting the Visual barrier.
Precast autoclaved aerated concrete Visual barrier will be paid for at the Contract Unit Price bid per square
foot (meter). Payment is full compensation for furnishing materials, including steel supports, and for erecting
the Visual barrier, including graffiti-proof coating
Additional barrier payment criteria: 10441044104410441044
Barriers will be paid at the plan quantity plus or minus any authorized changes, or adjustments due to ground
line elevation varying from plan.
Payment will be made under:
Item No. 625 Visual Barrier Per square foot (meter).
625.5.01 Adjustments
General Provisions 101 through 150.. 1045 1045 1045 1045 1045
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