Oyster as an Aggregate

Question

Is oyster a good aggregate for concrete? Why and why not?

Answer 1

Hello Rik,

Defining Good Aggregate is important in this question. It depends on the application, some concrete applications require strength and material requirements which are lower than let say concrete used for foundation elements. And even then some foundation elements require extreme and very specific material requirements.

The implementation of "oyster" which I understand you mean oyster shell material needs to be processed and must be tested as not all oyster shells are the same. Consistency is key when sourcing any material for concrete mixing in most projects.

As I understand these shells do have potential as a form of aggregate but need to be treated and tested before hand. As there is no actual large market for this type of material, then the process becomes "inefficient" and expensive.

Only in the material sense, some studies have shown that oyster shell sand after proper treatment can increase concrete strength and some studies indicate the inclusion for fly ash to supplement it. In terms of using it as a replacement for construction, passing through regulation agencies will be the biggest challenge for any new, modern, and "unconventional" aggregate.

Hope this helps,

Daniel B.

Some reading material in the matter. https://doi.org/10.1016/j.matpr.2021.02.208