Minfei developed a setup to measure free and restrained autogenous and thermal shrinkage in concrete. The set-up is similar to existing TSTM (Temperature Stress Testing Machine) that are common at many universities. However, the size of our current version is a bit smaller and thus easier to handle and it is positioned vertically to circumvent friction with formwork at early age. The restrained version is build inside a hydraulic universal testing machine (Instron) with allows for fast and active control. In the same machine on the same sample we can do creep and relaxation tests during the hydration of the material. The temperature in the material can be accurately controlled by temperature flow through the moulds (blue tubes in the pictures). Results look very promising and will be shared later.
Free and restrained autogenous shrinkage in dogbone shaped concrete specimens
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