High density mineral wool hasgood sound deadeningproperties and can be encasedin either high specification pre-galvanised and painted steel oraluminium panels to produce alight weight sound absorbingbarrier. These are usedextensively throughout Europewithin urban areas and onstructures.

Each panel is made ofcorrosion- resistant aluminiumsteel, and perforated foracoustical absorption.

The size and pattern of theperforations are designed toprotect and maintain thesound-absorptive capability ofthe acoustic fill inside thepanels. The reverse side awayfrom the road, is made of non-perforated galvanised steel,also corrosion-resistant.

Metal structures cut the buildup of reverberant soundbetween parallel barriers,resulting in noise reductionhigher than that provided bythe hard-surface alternates.

A unique design feature ofthe aluminium and steel barrierconstruction is that individualpanels can be removed andreplaced. Panels are not bolted,welded, or otherwisepermanently fastened to eachother or to the support posts.

Should replacement be calledfor as a result of structuraldamage, no more than threeworkmen using ordinary handtools will be able to do the job.

The light weight – 6lb/sq ft(29.3 kg/m2) of the noise shieldpanels also make them theprime choice for barrierconstruction atop existingbridges, overpasses, or otherelevated transit structureswhich cannot support concretepanels of the same thickness –4in. (102mm) weighing in at aheavy 37 lb/sq ft (180.6 kgm2).

ALUMINIUMAND STEELBARRIERS

GRAMM

GRAMM BARRIER SYSTEMS LTDENVIRONMENTAL AND SECURITY BARRIER SPECIALIST

Steel galvanised and painted absorptive noise barriers designed for heavy traffic on main roads and motorways.

Combined aluminium absorpative and acrylic barrier system allowing bespoke architectural designs.

Aluminium modular system designed for easyinstallations on roads and railways.

Lightweight aluminium panel system suitable forbridges and underpasses.

All components aremaintenance -freeand recyclable.

FS 57589

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Caption to come

Octive Band, Hz 63 125 250 500 1K 2K 4K 8K STC NRCSound Transmission Loss, dB - - - - - - - - - -Sound Absorbption Coefficients - - - - - - - - - -

GRAMMContact

Stephen WhittleTel: 01323 872243 • Fax: 01323 872244

E-mail SteveWhitt@aol.comwww.grammbarriers.com

Technical specification:

Acoustic Performance: The acoustic performance meets all the current UK andEuropean regulations for roadside applications.

Random Incidence Sound Absorption:• Tested to BS 3638 (BS EN 20345: 1993)• Noise reduction coefficient (250-2000Hz): a=0.98• Tested to proposed CEN standard, pr EN 1793:1• DLa= 16 dB, Class: A4

Sound Insulation:• Tested to BS 2750: Part 3 (BS EN20140: Part 3)

(ISO 140/111)• Weighted Sound Reduction Index, Rw,= 30dB

(BS 5821: 1984)• Tested to proposed CEN standard, pr EN 1793:2• DLR= 24.6 dB, Class: B3

Panel Dimensions:Post Spacing: 2.0m 3.0m 4.0mPanel Length: 1.95m 2.95m 3.95m*Effective Panel Height: 0.4m** 0.6m 0.8m**Panel Width: 0.125m Nominal

* Other dimensions to special order.** Nominal dimensions and to special order only.

Posts:Structural Steel Universal Columns from low carbon steel to BSEN 10025, 152mm x 152mm for standard systems.

Absorbant Infil:75mm Thick mineral wool with black glass tissue face. Density 60kg/cubic meter.

Finish:Top and bottom Aluminium profiles in natural finish.**Panels in a choice of Polyester powder coated, semi gloss(30%) coloursPosts in a hot dip galvanised finish to BS 729.*** Can be powder coated to special order.

A Perfected SystemGramm noiseprotection elementsmeet all requirements:

• exceeding the noisevalues demanded• guarantee a large measure oftraffic safety• are steady and dimensionally stable• they are resistant to ageing and corrosion• they are dimensionally accurate• they are colourfast and resistant to fire• they are resist impacts from stones and are largelymaintenance-free

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