Smart Sensors consists a rugged, waterproof, wireless sensor/logger for monitoring the temperature of concrete from fresh stage to hardened stage. It can be placed in the concrete formwork at the time of casting to monitor the temperature of concrete on site. The continuous measurements are recorded and can be downloaded at any time during the concrete setting and hardening stages.
The continuous monitoring of concrete temperature can be used as a QC/QA procedure as well as maturity-based strength estimation of concrete. The field monitoring of concrete temperature and strength using maturity meter can also help with optimizing the formwork removal time, application of load on the structure, stressing of post-tensioned cables, as well as opening traffic on concrete pavement.
|Parameters||Conventional Testing||Smart Sensor|
|Frequency||For 100m3 of concrete, minimum 30 cube specimen required (As Per IS 456).||PTSI recommends two sensor for 100m3 of concrete.|
|Curing||Continuous curing is required to maintain the temperature of the concrete element as well as w/c ratio.||Temperature data are available at each 30 minute interval, which helps to provide adequate curing needed.|
|Securing||Cube specimen should be accurate in size.||Not required.|
|Preparing||Concrete cube specimen should be prepared with controlled monitoring under supervision of engineer as per IS:516.||Not required. Once installed it is ready to use.|
|Testing||Concrete cube specimen are taken for testing on 3rd, 7th and 28th day to external labs.||Gives real time data of temperature (°C), maturity (°C — Hours) and strength (MPa)|
|Timing||Work is being delayed, due to waiting for the results of 3rd, 7th and 28th day.||Work can be planned after getting real time concrete strength data collected in 24 hours.|
|Record||Reports of tests conducted on 3rd, 7th and 28th day.||Sensor gives data of all 30 days at every interval of 30 minutes.|
|Workmanship||Skilled manpower is needed as per IS:516 to follow the method of measuring strength of concrete.||Not Required.|
|Prediction||No prediction until breakage of specimens||Prediction of 28 days strength can be derived.|
|Costing||Less Expensive & less information||Little Expensive, but hassle free. Overall cost effective.|
|Construction flow||Prediction becomes difficult due to limited number of readings obtained which makes it impossible to pre-plan the work-flow.||Data can be extrapolated for strength prediction, which helps in pre-planning of work schedule.|