砂浆层尺寸变化监测仪

Monitoring the dimensional variations of a screed during drying process

砂浆层尺寸变化监测仪Description - Principle

Curling, warping, shrinkage and cracking are the most common effects during the process of drying screeds made of Portlａnd cement and aggregates. The drying process taking place from the top surface, the upper surfaces usually shrink first, resulting in a tendency for the screeds to curl upwards at the edges.

In order to characterize these phenomena, CAD Instruments developed, in collaboration with the Louis Vicat Technical Centre in L'Isle d'Abeau and based on original research made at LGCIE*, a special device 砂浆层尺寸变化监测仪 to follow the curling, shrinking and drying process on reduced size mortar slab.

砂浆层尺寸变化监测仪技术指标：

A 30 x 30 x 3 cm mold is used to cast a mortar screed. A balance is used to measure continuously the mass loss. 24 hours after casting, the slab is equipped with:

• 4 vertical positioning sensors placed at the corners to measure the curling

• 2 horizontal positioning sensors to control the shrinkage

砂浆层尺寸变化监测仪软件

A special software is used to store the mass loss and various sensors positions versus time. Direct export of data to Excel can be used for advanced treatment or modeling.

* Georgin, J.F.; Ambroise, J.; Péra, J.; Reynouard, J.M. Development of self-leveling screed based on calcium sulfoaluminate cement:   Modelling of curling due to drying. Cement and Concrete Composites (2008), 30 (9), 769-778.