Mix proportions and properties of ultra high strength concrete produced using local materials

الملخص EN

The development of ultra high strength concrete (UHSC) started late in the 20th century by modifying some of the existing rules for designing concrete composition and selecting materials in high strength concrete (HSC) Beside its high compressive strength (up to 200 MPa), UHSC also have considerably improved tensile strength, stiffness and durability that is why it is termed ultra high performance concretes (UHPC).

UHSC finds wide use in high rise buildings, bridges, airports, power plants etc.

A two phase experimental program is designed.

The first phase was designed to study the ability to produce UHSC using different locally available materials in Egypt.

In this phase, a total of (72) mix design was used to produce UHSC and to study the effect of using different materials such as cement type and content, silica fume content, coarse aggregate type and content, fine aggregate type and content, existence of quartz powder, existence of steel fiber, and water to binder ratios on the compressive strength.

Phase two was designed to investigate the different fresh and hardened properties and the durability such as slump flow, flexural strength, indirect tensile strength, abrasion, drying shrinkage, absorption, permeability and modulus of elasticity, of one selected mix from the first phase which had the highest compressive strength and compare it with a conventional high strength concrete mix.

From the analysis and discussion obtained of this research, UHSC mixes were produced using local available materials in Egypt.

UHSC improves the mechanical properties of concrete and has excellent resistance to abrasion, water absorption and water penetration.