AMTS L-Bar Prisms
L-Bar Prisms are versatile survey prisms used with AMTS to monitor displacements and deformations of structures. The L-Bar bracket provides easy installation on almost any location: tunnel walls, building facades, soldier piles, retaining walls, bridge decks, and more. Datasheet
L-Bar Mini Prism
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The L-Bar Mini Prism is installed on tunnel walls, building facades, foundation slabs, retaining walls, and almost any other location. It is used for both monitoring points and control points.
Prism: 25 mm optical glass with silver backing and clear appearance.
Offset: -25.5 mm for Topcon, Trimble,etc. +8.92 mm for Leica.
L-Bar Bracket: Black anodized aluminum, 3 inch arms, two 5/16 inch holes for mounting screws.
L-Bar Micro Prism
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The L-Bar Micro Prism is a tiny 0.5 inch prism designed for low visual impact and is nearly invisible in most environments. This prism is best used for indoor monitoring points.
Prism: 12.7 mm optical glass prism with silver anti-reflection coating.
Offset: -17.5 mm for Topcon, Trimble, etc.
Bracket: Black-anodized aluminum bracket has 25 mm arms and a single mounting hole.
L-Bar 360 Prism
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The L-Bar 360° Prism can be targeted by two more AMTS as a monitoring point, control point, or a tie-in point between separate AMTS networks.
Prism: Omni-directional prism consists of 6 triple prisms.
Offset: -6.5 for Topcon and Trimble, 27.9 for Leica.
Bracket: Black-anodized aluminum bracket has 3-inch arms and two 5/16-inch holes for mounting screws.
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L-Bar Prisms on Soldier Piles
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L-Bar Prisms on Facade
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L-Bar Prisms in Tunnel
Advantages L-Bar Prisms
Easy Installation: The compact L-Bar bracket can be installed in any orientation and fits nearly any location.
Durable: The L-Bar prism is waterproof and dustproof, suitable for any environment.
Low Visual Impact: L-Bar prisms are compact and almost unnoticeable from street level.
Cost Effective: L-Bar prisms are relatively inexpensive and provide a low cost per monitored point.
Installation
- Choose locations that provide a clear line of sight between the L-Bar prism and the AMTS.
- Determine the best orientation for the L-Bar bracket, install the anchors, and mount the bracket. Magnetic bases are also available and eliminate any drilling.
- Attach the prism to the bracket, rotate it to face the AMTS, and tighten the mounting screw.