Material Behavior

Effects of Silica Powder and Cement Type of Durability of Ultra High Performance Concrete (UHPC)

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Abstract

Ultra-high performance concrete (UHPC) has been shown to achieve exceptionally high strength in compression and high ductility through optimization of the particle packing density of the material’s matrix. This dense structure also offers UHPCs the ability to resist deterioration due to other environmental factors, such as freeze-thaw and the penetration of salts and ions from the surface. Robust UHPCs enables structures to last longer, reduces the cost of maintenance and helps achieve a significantly more sustainable infrastructure. To assess these parameters for UHPC, several non-proprietary blends are investigated by assessing the materials’ resistance to freeze-thaw cycles, ingress of chlorides as well as the presence and distribution of air voids. The main experimental variables are cement type and the quantity of silica powder, which varies from 0% to 25% of the cement weight. All mixes displayed extremely low levels of chloride ion penetration and high resistance to freeze-thaw with mass loss well below the limit in over 60 cycles of freeze-thaw. Analysis of the test data indicates that the silica powder content has little influence on these performance criteria.

Keywords: durability, air-void system, freeze-thaw, rapid chloride penetration, ultra-high performance concrete (UHPC), silica powder

How to Cite:

Alkaysi, M., El-Tawil, S., Hansen, W. & Liu, Z., (2016) “Effects of Silica Powder and Cement Type of Durability of Ultra High Performance Concrete (UHPC)”, International Interactive Symposium on Ultra-High Performance Concrete 1(1). doi: https://doi.org/10.21838/uhpc.2016.87