This guide outlines the things that you will need to think about before you order a ShapeArray (SAA). It is presented in the form of questions that you should be asking prior to ordering a ShapeArray. If you have any questions, contact SAAsales@measurand.com.
Step 1 - What type of ShapeArray do I need?
The type of ShapeArray required depends on the application. Questions you should be asking include the following:
- What are you planning to monitor with the ShapeArray?
- What are you trying to determine using ShapeArray?
- What is the geotechnical reason for monitoring?
- Is the installation horizontal, vertical, or in the cross section of a tunnel?
- How much deformation are you expecting?
In general Measurand recommends the following:
- For long term monitoring of deformation, use SAAF.
- For short term applications with multiple re-use, use SAAScan.
Step 2 - How is a ShapeArray built?
SAAF is composed of a series of rigid segments separated by flexible joints. Segment lengths can be either 305 mm or 500 mm. The most commonly ordered segment length is 500 mm; however, if you are expecting significant deformation, consider using the 305 mm length segments.
SAAScan is composed of a series of rigid segments separated by flexible joints. Rugged construction is used to allow for repetitive insertions and removal from boreholes. Segment lengths are limited to 500 mm on SAAScan.
Step 3 - How do I connect to a ShapeArray?
A single 18 AWG communication cable extends from the top of every ShapeArray providing both power and communication to the sensors inside. Every ShapeArray has 15 m of cable attached as standard, but this can be lengthened as required. For maximum cable lengths, refer to the following articles from our manuals:
If you are extending the communication cable, consider the use of an SAASPD to provide surge protection from nearby lightning strikes.
Step 4 - What length of ShapeArray should I order?
The length of the ShapeArray should be outlined in the project specifications. Measurand cannot specify what length is required for your project. The overall length of the ShapeArray includes the sensorized segments, and unsensorized components such as the PEX tubing. For more information, refer to the following articles from our manuals:
For deformation monitoring, make sure that one end of the ShapeArray is installed into stable soil to ensure a stable reference point. Alternatively, measurements can be made to one end of the ShapeArray via surveying techniques to guarantee a stable reference.
Step 5 - How do I collect data?
Manual data collection can be done using a PC running SAARecorder, or smartphone or tablet running SAADroid. This requires the use of an SAA Field Power Unit (SAAFPU).
Automated measurements can be done using a Campbell Scientific data logger. Supported data loggers include the following:
- CR300 - this logger is limited to five SAAs consisting of no more than 300 segments total
Step 6 - How do I do automated data collection on a remote site?
Automating data collection on a remote site requires the use of a data acquisition system which includes the following:
- A data logger
- Solar panel and power regulator
- An SAA232 or SAA232-5
Data acquisition system components are housed in enclosures to protect them from the elements. These items can be purchased from Measurand or Campbell Scientific, or other third-party system integrators, such as RST or GKM Consultants.
Step 7 - How do I get data transferred remotely to my office?
Transferring data remotely to an office requires the use of a remote communications device, such as one of the following:
- cellular modem
- satellite modem
- wireless modem
Measurand does not sell these devices. You should contact your local Campbell Scientific representative for help sourcing the appropriate modem for your application or geographic area.
Step 8 - Does Measurand do installations?
Measurand can provide on-site training and assistance for a fee, but we do not perform any of the physical installation of the ShapeArray.
Step 9 - Where do I obtain the casing required for SAAF installation?
SAAF should be installed inside a 27 mm inside diameter PVC conduit. The best source of this casing is local home improvement stores. Appropriately sized conduit is typically found in the electrical conduit department in North America and in the plumbing conduit section in Europe. For more information, refer to the Conduit section in the ShapeArray Installation manual.
NOTE: Measurand does not supply this conduit
Step 10 - How many times can I re-use a ShapeArray?
The number of times a ShapeArray can be reused depends heavily on the type of ShapeArray and how it is being used.
- If an SAAF has not undergone significant displacement, and it is removed and stored on its reel properly, an SAAF can be re-used up to three times in vertical installations.
- SAAF can be re-used in horizontal installations indefinitely, as long as the waterproof coverings are still in good shape, and the segments are still straight.
SAAScan and SAAX
- SAAScan and SAAX have hydraulic hose joints which are resistant to twist. These can be re-used indefinitely as long as the joints are intact and the segments are straight.