Consolidating stiff concrete mold
Fourth, nanotechnology shows promise in the development of smart sensors.Because concrete develops its properties (such as strength) with time and chemical reactions (called hydration), it is critical to monitor concrete at early ages.These microstructural phases govern the macroscopic properties of cementitious materials, such as strength, ductility (pliability), early-age rheology (flow), and durability.Controlling the macroscopic properties demands a detailed knowledge of the structure of these phases at the smallest size level. The increased traffic volume has generated an escalating need for high-performance, durable construction materials for roadway pavements. Department of Transportation, the current backlog of unfunded but needed repairs and improvements totals 5 billion.
The outcomes of this project led to further research focused on additional themes that are supported by multiple organizations.This technique originated from the Mohs scale of mineral hardness developed in 1812, in which one material is considered to be harder if it can leave a permanent scratch on another material.In nanoindentation, a researcher pushes a small probe into a hardened concrete sample and then plots the load applied by the probe versus its displacement in the sample.In this effort, the researchers developed a new method to monitor the properties of concrete pavement at its early ages just after it is placed.
This new method relies on measuring the amount of ultrasonic sound wave returned after striking the surface of concrete pavement.These four photos show concrete at various length scales: 10 millimeters, mm (0.3937 inch), 500 micrometers, µm (0.01969 inch); 2 µm (0.00007874 inch); and 500 nanometers, nm (0.00001969 inch).