Compressive Fatigue Behaviour of High-Strength Concrete and Mortar: Experimental Investigations and Computational...

Area of Science:

• Materials Science
• Civil Engineering
• Structural Engineering

Background:

• High-strength concrete and mortar are crucial in modern construction.
• Understanding their fatigue behavior under compressive loading is essential for structural integrity.
• The role of coarse aggregates in concrete's fatigue performance requires detailed investigation.

Purpose of the Study:

• To comparatively investigate the compressive fatigue behavior of high-strength concrete and mortar.
• To analyze the influence of basalt coarse aggregate on the fatigue performance of high-strength concrete.
• To validate experimental findings with computational simulations.

Main Methods:

• Experimental analysis using macroscopic damage indicators: strain, stiffness, and acoustic emission hits.
• Computational simulation employing a finite element approach with a gradient-enhanced equivalent strain-based damage model and a fatigue model.
• Modeling concrete with a random distribution of spherically shaped basalt aggregates.

Main Results:

• Distinct differences in fatigue behavior were observed between concrete and mortar, particularly at lower stress levels.
• Basalt coarse aggregate improved the fatigue behavior of concrete at lower stress levels.
• A potential negative effect of basalt aggregate was indicated at higher stress levels.

Conclusions:

• Basalt coarse aggregate significantly influences the fatigue performance of high-strength concrete.
• The finite element model accurately predicts the strain development in concrete and mortar under fatigue loading.
• Experimental and computational results show excellent agreement, validating the proposed modeling approach.