Engineering properties of controlled low-strength materials containing waste oyster shells

To evaluate the practical application of waste oyster shells (WOS) as controlled low-strength materials (CLSM), using a reference sample and four fine aggregate replacement 5%, 10%, 15% and 20% WOS sand, and the cement was replaced by 20% fly ash of the materials were tested. The hardened properties and the durability are tested and other various engineering properties are investigated. The experimental results demonstrate that there was no significant reduction in the compressive strength up to 20% of dosages of WOS sand instead of sand, and a proper amount of fly ash material and WOS sand for the replacement of the fine aggregate in cement mortar fills material pores, reduces the absorption rate. WOS sand can be resources of pure calcareous materials and effective in replacement of sand, indicating appropriate application of oyster shells, it is feasible to use in CLSM.