Alert Solutions BV Product Specification Sheet
GeoBeads™ PRELIMINARY Rev 0.1, 05/2009
GeoBeads SI1.D .DI GeoBeads Sensor Node for Inclination and Displacement Array Integrated Digital Nodes for building up an array of inin place inclinometers for automated monitoring of soil and construction deformation. Description The GeoBeads SI1.DI integrates inclination ((I; in two degrees of freedom) measurement and absolute displacement determination into a small form factor, highly reliable digital network node. A large number of SI1.DI nodes can be connected together to form an array of segments in order to determine the deformation profile over the full array length. The array is connected via a digital serial bus to the GeoBeads network controller NC1.xx and as such can be incorporated incorpo in a large area, geotechnical monitoring network network. This network enables real-time real data acquisition, isition, remote network management and live insight into geotechnical ground stability. Features
Measurement of Inclination and Displacement Multiple sensor nodes (segments) may be connected to form a continuous array Suitable for both vertical or horizontal placement Small form factor enables installation in small diameter casings Unlimited network scalability for large scale area monitoring Measurement frequency ency remotely manageable Data real time and online available
Typical Application Areas Soil deformation of levees, dikes ikes, dams and mountain slopes Steel pile walls, construction nstruction pits p (Reinforced) concrete oncrete structures such as foundations, floors, and bridges Rail and roadway embankment settlement
Š Alert Solutions BV, 2009. All rights reserved.
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Alert Solutions BV Product Specification Sheet
GeoBeads™ PRELIMINARY Rev 0.1, 05/2009
Technical Specifications Inclinometer (I) Range: Resolution: Accuracy: Measurement Principle: Digitization Resolution: Operating Temperature: Storage Temperature: Displacement (D) Available segment lengths: Resolution: Accuracy:
±90° primary axis, ±15° secondary axis 0.005° 0.01° MEMS based three axis high sensitivity digital accelerometer 16 bit (65536 levels over full scale, 16384 level over 90°) -40 … 85 °C -40 … 125 °C
0.50, 1.00 and 2.00 meters, 2 and 5 feet Custom lengths upon request 0.01% of segment length, over 0° .. 15° range 0.04% of segment length, over 0° .. 15° range
GeoBeads inclination and displacement measurement principle
dF
dS X
Y Movement of the GeoBeads sensor node is translated into two directional inclination measurements (X- and Y-axis). GeoBeads converts these measurements into degrees in frontside angle (dF)and sideways angle (dS). The vector of these angles, capturing the combined direction and magnitude of movement, is presented as well. Displacement of an inclino-array segment of length L is caluclated as follows: dA = ∆x over segment length = L sin(dF) dB = ∆y over segment length = L sin(dS)
© Alert Solutions BV, 2009. All rights reserved.
X
X
Y
Y Example Measurement output: Inclination dF = 4° Inclination dS = 3° Inclination (magnitude) = √ (4° ^2 + 3° ^2) = 5° A plot of α displays the direction of movement. L = 500 millimeters (0.5 meters) dA = 34.9 millimeters dB = 26.2 millimeters
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Alert Solutions BV Product Specification Sheet
Electrical Supply Voltage: Power consumption:
Network communication CPU:
GeoBeads™ PRELIMINARY Rev 0.1, 05/2009
6-30 Vdc, typical 24 Vdc measurement mode 135mW (<6mA @ 24Vdc), sleep mode <1mW (<40uA @ 24 Vdc)
Communications: Nodes per cable: Cables per network: Data Format: Sampling Frequency:
On-board 16-bit RISC processor, 12-Bit A/D Converter, ultra low power consumption digital serial bus according to EIA-485 (aka RS485) standard 1 … 256 unlimited ASCII text lines in comma separated fields (.csv compatible) adjustable
Housing Material: Filling material: Dimensions: Weight: Rating:
stainless steel (Grade 316) poly-urethane epoxy diameter 22 mm, length 157 mm ~300 grams IP68 or better
Cables Configuration: Options: Jacket: Outer diameter:
data bus; 22 … 28 AWG twisted pair power line; 2 conductors 18 … 22 AWG. Shielding, metal braiding, Kevlar fiber strain relief, rodent resistant Poly-urethane or Teflon 4 … 7.5 mm depending on included options
How to reach us: Home Page: www.alertsolutions.nl Address: Alert Solutions BV Rotterdamseweg 145 2628 AL Delft, The Netherlands +31 15 2568551 info@alertsolutions.nl
© Alert Solutions BV, 2009. All rights reserved.
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Alert Solutions BV Product Specification Sheet
GeoBeadsâ&#x201E;˘ PRELIMINARY Rev 0.1, 05/2009
Field Project Data Graph Example
Ground deformation Monitoring
Absolute displacement profile (direction A)
Depth [in m]
Week 8 Week 10
Week 7 Week 9
Steel pile wall
Week 7 Week 9
-100
0
0
-2
-2
-4
-4
-6
-6
-8
-8
-10
-12
-75
-50
-25
0
Displacement in mm
25
50
Depth [in m]
(January 2009)
Absolute displacement measurements to a depth of 22 meters show ground deformation along steel pile wall
Absolute displacement profile (direction B) Week 8 Week 10
-10
-12
-14
-14
-16
-16
-18
-18
-20
-20
-22
-22 -50
-25
0
25
50
75
100
Displacement in mm
All of the information in this brochure is provisional. We reserve the right to make changes to the product and specifications.
Š Alert Solutions BV, 2009. All rights reserved.
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