Method and systems relating to construction material assessment
Hundreds of thousands of concrete bridges, buildings etc. and hundreds of billions of tons of concrete require characterization throughout the process from manufacture to pouring and curing and on throughout service life. The characterization may relate to initial concrete properties, projected concrete properties, framework removal, corrosion, failure etc. Accordingly, a variety of measurements such as water content, electrical resistivity, and half-cell corrosion potential for example would be beneficially implemented as easy to use field test equipment or embedded sensors allowing lifetime monitoring to be performed rather than discrete assessments when issues become evident.
1. A method comprising;
providing an electrical measurement system for measuring an electrical characteristic of a concrete structure;
providing at least one beacon of a plurality of beacons, each beacon including a predetermined portion of a transceiver providing pulses of a predetermined format;
providing a global positioning system to provide a global position;
determining at least a relative location of a plurality of relative locations, each relative location being that of the electrical measurement system relative to a predetermined subset of the plurality of beacons; and
storing measurements of the electrical characteristic together with the plurality of relative locations and the global position.
2. The method according to claim 1 , wherein
measuring the electrical characteristic of the concrete structure comprises:
generating an electrical pulse which is applied with a first probe to a first part of the concrete structure;
measuring with the electrical measurement system an output electrical signal with a second probe applied to a second part of the concrete structure, the output electrical signal being the result of application of the electrical pulse to the first part of the concrete structure; and
applying a predetermined signal processing algorithm to the output electrical signal to generate a low frequency electrical characteristic of the concrete structure.
3. The method according to claim 1 , wherein
measuring the electrical characteristic of the concrete structure comprises:
applying a plurality of first electrical signals to the concrete structure via a pair of first probes, each first electrical signal at a different frequency;
measuring a plurality of second electrical signals via a second pair of probes disposed inline with the first pair of probes and between the first pair of probes; and
determining the electrical characteristic in dependence upon a frequency response established in dependence upon the plurality of second electrical signals.
4. The method according to claim 1 , wherein
measuring the electrical characteristic of the concrete structure comprises:
applying a first electrical signal to the concrete structure via a pair of first probes;
measuring a plurality of second electrical signals via a second pair of probes disposed inline with the first pair of probes and between the first pair of probes, each second electrical signal at a different time subsequent to the application of the first electrical signal; and
determining the electrical characteristic in dependence upon the time dependent response established in dependence upon the plurality of second electrical signals.
5. The method according to claim 1 , wherein
at least one of the first part of the concrete structure and the second part of the concrete structure is a reinforcing bar; and the electrical measurement performed is the measurement of an electrical potential.
6. The method according to claim 1 , wherein
storing the electrical measurement comprises transmitting the electrical measurement from the electrical measurement system to a microprocessor based device via a wireless interface operating according to a predetermined wireless standard and storing the electrical measurement within a memory of the device.
7. The method according to claim 1 , further comprising
at least one of:
establishing a corrosion state of a reinforcement within the concrete structure in dependence upon the electrical characteristic; and
establishing a corrosion state of a reinforcement within the concrete structure in dependence upon the electrical characteristic and the result of applying a predetermined signal processing algorithm to the output electrical signal.
8. The method according to claim 1 , wherein
the first part of the concrete structure is a reinforcing bar; and
the electrical pulse is applied via electromagnetic induction.
9. The method according to claim 1 , wherein
measuring the electrical characteristic of the concrete structure comprises:
applying a first electrical signal to the concrete structure via a pair of first probes;
measuring one or more second electrical signals via a second pair of probes disposed at 45° with respect to the first pair of probes and having a spacing less than the first pair of probes;
applying a third electrical signal to the concrete structure via a pair of third probes which are orthogonal to the pair of first probes;
measuring one or more fourth electrical signals via the second pair of probes; and
determining one or more electrical characteristics in dependence upon the one or more third electrical signals and the one or more fourth electrical signals.
10. A system comprising;
an electrical measurement system comprising a microprocessor to determine an electrical characteristic of a concrete structure;
at least one beacon of a plurality of beacons, each beacon including a predetermined portion of a transceiver providing pulses of a predetermined format;
a global positioning receiver to provide a global position; and
the microprocessor for determining at least a relative location of a plurality of relative locations, each relative location being that of the electrical measurement system relative to a predetermined subset of the plurality of beacons and storing measurements of the electrical characteristic together with the plurality of relative locations and the global position within a memory.
11. The system according to claim 10 , wherein
electrical measurement system measures the electrical characteristic of the concrete structure by:
generating an electrical pulse which is applied with a first probe to a first part of the concrete structure;
measuring with the electrical measurement system an output electrical signal with a second probe applied to a second part of the concrete structure, the output electrical signal being the result of application of the electrical pulse to the first part of the concrete structure; and
applying a predetermined signal processing algorithm to the output electrical signal to generate a low frequency electrical characteristic of the concrete structure.
12. The system according to claim 10 , wherein
electrical measurement system measures the electrical characteristic of the concrete structure by:
applying a plurality of first electrical signals to the concrete structure via a pair of first probes, each first electrical signal at a different frequency;
measuring a plurality of second electrical signals via a second pair of probes disposed inline with the first pair of probes and between the first pair of probes; and
determining the electrical characteristic in dependence upon a frequency response established in dependence upon the plurality of second electrical signals.
13. The system according to claim 10 , wherein
electrical measurement system measures the electrical characteristic of the concrete structure by:
applying a first electrical signal to the concrete structure via a pair of first probes;
measuring a plurality of second electrical signals via a second pair of probes disposed inline with the first pair of probes and between the first pair of probes, each second electrical signal at a different time subsequent to the application of the first electrical signal; and
determining the electrical characteristic in dependence upon the time dependent response established in dependence upon the plurality of second electrical signals.
14. The system according to claim 10 , wherein
at least one of the first part of the concrete structure and the second part of the concrete structure is a reinforcing bar; and the electrical measurement performed is the measurement of an electrical potential.
15. The system according to claim 10 , wherein
storing the electrical measurement comprises transmitting the electrical measurement from the electrical measurement system to another device via a wireless interface operating according to a predetermined wireless standard and storing the electrical measurement within a memory of the other device.
16. The system according to claim 10 , further comprising
the electrical characteristic of the concrete structure is determined by the electrical measurement system by:
establishing a corrosion state of a reinforcement within the concrete structure in dependence upon the electrical characteristic; and
establishing a corrosion state of a reinforcement within the concrete structure in dependence upon the electrical characteristic and the result of applying a predetermined signal processing algorithm to the output electrical signal.
17. The system according to claim 10 , wherein
the first part of the concrete structure is a reinforcing bar; and
the electrical measurement system applies an electrical pulse to the concrete structure via electromagnetic induction.
18. The system according to claim 10 , wherein
electrical measurement system measures the electrical characteristic of the concrete structure by:
applying a first electrical signal to the concrete structure via a pair of first probes;
measuring one or more second electrical signals via a second pair of probes disposed at 45° with respect to the first pair of probes and having a spacing less than the first pair of probes;
applying a third electrical signal to the concrete structure via a pair of third probes which are orthogonal to the pair of first probes;
measuring one or more fourth electrical signals via the second pair of probes; and
determining one or more electrical characteristics in dependence upon the one or more third electrical signals and the one or more fourth electrical signals.