Measuring the Restrained Shrinkage According to ASTM C1581
Standard Test Method for Determining Age at Cracking and Induced Tensile Stress
Characteristics of Mortar and Concrete under Restrained Shrinkage
This test method covers the laboratory determination of the age at cracking and induced tensile stress characteristics of mortar or concrete specimens under restrained shrinkage. The procedure can be used to determine the effects of variations in the proportions and material properties of mortar or concrete on cracking due to both drying shrinkage and deformations caused by autogenous shrinkage and heat of hydration.
A sample of freshly mixed mortar or concrete is compacted in a circular mold around an instrumented steel ring. The compressive strain developed in the steel ring caused by shrinkage of the mortar or concrete specimen is measured with 4 strain gages from the time of casting. Cracking of the test specimen is indicated by a sudden decrease in the steel ring strain. The age at cracking and the rate of tensile stress development in the test specimen are indicators of the materials resistance to cracking under restrained shrinkage.*1
1 cited from the standard.
Steel ring strain vs. time. The specimen is cracking after 6.8 days at a strain of about 100 µm/m : ASTM C1581
On each steel ring a strain-gage amplifier and thermocouple type K input is mounted. The data of up to 5 rings are digitally transferred to the data-logger.
A data-logger supplied with the system records strain gage data and store it in the logger as standard ASCII files. Optional a synchronous registration of temperature and humidity is possible.
The logger has a network interface (Ethernet). So you can easily integrate it into local intranet. With a standard web-browser software you can readout the data and visualize it. For further data handling we recommend Microsoft Excel ® ore any similar visualization program. The data are visualized online graphical and numerical on the screen. No special PC software is necessary. You need only your browser-software like Firefox, Chrome, Edge, Opera or Internet-Explorer ® .
- ASTM C1581 / C1581M - 09a
Standard Test Method for Determining Age at Cracking and Induced Tensile Stress Characteristics of Mortar and Concrete under Restrained Shrinkage
- Sören Eppers
Assessing the autogenous shrinkage cracking propensity of con
crete by means of the restrained ring test
Die Bewertung der autogenen Schwindrissneigung von Beton mit Hilfe des Ring-Tests
- Sören Eppers, Christoph Müller
On the examination of the autogenous shrinkage cracking propensity by means of the restrained ring test with particular consideration of temperature influences
- Prof. Dr.-Ing. Harald S. Müller, Dipl.-Geol. Dipl.-Min. Astrid Hirsch, Dr.-Ing. Vladislav Kvitsel Institut für Massivbau und Baustofftechnologie, Karlsruher Institut für Technologie (KIT)
Prof. Dr.-Ing. Rolf Silbereisen, Dipl.-Ing. Carsten Becker CEMEX Deutschland AG
Schwindarmer Beton Entwicklung und Möglichkeiten
- Frank Apicella, BASF Corp - Construction Chemicals
"Crack-Free" Repair Materials ... Are We There Yet ?
Minnesota Concrete Council
- Jae-Heum Moon,Farshad Rajabipour,Brad Pease,and Jason Weiss
Quantifying the Influence of Specimen Geometry on the Results of the Restrained Ring Test
Journal of ASTM International, Vol. 3, No. 8, Paper ID JAI100436
- Henkensiefken et al.2008 CBC
Reducing Restrained Shrinkage Cracking in Concrete: Examining the Behavior of Self-Curing Concrete Made using Different Volumes of Saturated Lightweight Aggregate
- Olayinka Gbolahan Oladiran
Assessment of restrained shrinkage cracking of concrete through elliptical rings, Brunel University School of Engineering and Design, PhD Theses, 2014
- Steven M. Soltesz, Mike Dunning, Mark Joerger, James Lundy
Concrete Patching Guide, Oregon Department of Transportation, Research Unit, 2003
Scope of Delivery:
Shrinkage Ring Order code: S00031:
- ASTM Shrinkage ring made of steel with 4 strain gages. Thickness 13 mm, outer diameter 330 mm, height 150 mm, weight 15.5 kg. Other sizes on request.
- Strain gage amplifier, thermocouple type K input and digitizing unit, mounted inside the inner ring. Serial digital SMB bus interface to the data logger S0003.
- Outer ring made of stainless steel. Inner diameter 406 mm, height 150 mm.
- Specimen volume ca. 6.6 litres (1.74 US.liq.gal.). Specimen thickness ca. 35.5 mm.
- Base made of plastic.
- Bolts, nuts and washers for fixing the rings on the ground plate.
- Ring for covering the specimen.
Data Logger - Order Code: S0003:
- Data logger for with an interface for up to 5 rings S00031.
- Network interface and built in WEB-Server, software pre-installed.
- Sampling rate 10s..1h for at least 1 year (2 GByte)
- Option: environmental temperature and humidity measurement S0016
- User Manual
- Size: 24 x 21 x 6 cm, weight 1.8 kg