The bond between aggregate particles and the cement matrix is significantly influenced by the shape and surface texture of the aggregates. High-strength concretes benefit from a rougher texture, which leads to stronger bonding due to greater adhesion. Angular aggregates with larger surface areas also enhance this bond. The bonding quality, however, is complex to assess as no universally accepted test exists. Good bonding is indicated when a crushed concrete specimen shows some aggregate particles broken throughout and most of them separated from the matrix.
The strength of concrete is predominantly determined by the aggregate strength, as concrete's compressive strength cannot surpass the strength of the majority of the aggregate it contains. Aggregate strength information is typically derived from indirect tests such as the crushing value of bulk aggregate and the crushing strength of rock samples from which the aggregates are derived. It's observed that while high-strength aggregates contribute to overall strength, aggregates of moderate or low strength are beneficial for the structural integrity of concrete, as they can compress under thermal or hygral changes, reducing stress on the cement paste and thus preventing cracking.
From Chapter 5:
Now Playing
Aggregates and Water
139 Views
Aggregates and Water
96 Views
Aggregates and Water
141 Views
Aggregates and Water
294 Views
Aggregates and Water
267 Views
Aggregates and Water
393 Views
Aggregates and Water
73 Views
Aggregates and Water
83 Views
Aggregates and Water
103 Views
Aggregates and Water
299 Views
Aggregates and Water
190 Views
Aggregates and Water
240 Views
Aggregates and Water
219 Views
Aggregates and Water
392 Views
Aggregates and Water
251 Views
See More
Copyright © 2025 MyJoVE Corporation. All rights reserved