Spun concrete properties of power transmission line supports
The article presents results of investigation study of physical and mechanical properties of spun and vibrated samples. Heterogeneity of freshly placed concrete was assessed for change in water to cement proportion, residual water content, density throughout the spun sample height, as well as changes in mechanical properties of hardened concrete. Analysis of experimental data showed a significant change (up to 4%) in the average density of concrete throughout the spun sample, while the overall voids content in the sludge layer increased by almost 10%, and strength of concrete changes by 18-25% along the lift height. By using the method of least squares, a consistent change in the strength of concrete along the lift height of samples was observed. An experiment, assessing the bearing capacity of spun pylons, accounting for the resulting changes in strength of concrete along the wall height, was carried out.