Investigation of usability a sulphureous mine waste with high clay content as paste backfill

Paste filling mixtures are prepared from mine plant waste. Each mine waste contains different minerals due to its structure. Short and long term strength values of paste backfill depend on mineral content of waste which used in paste backfill mixture. The clay minerals contained in the waste are evaluated as a negative factor affecting the strength performance of the cemented paste backfill. Therefore, this thesis aims to investigate the potential of high clay content wastes to be a usable material in cemented paste backfill mixtures. The mixture prepared with the evaluated waste material was designed in relation to certain criteria in order to reach the appropriate cement paste backfill design. These criteria were solid ratio, slump, binder type and binder ratio. In addition to the samples prepared under these conditions, additional samples were prepared in which sand and fly ash addition were also examined. Paste backfill samples were subjected to uniaxial compressive strength (UCS) tests at 14-360 days of curing time to measure their strengths. It has been observed that paste backfill samples cannot reach high strength in short and long terms. It has been determined as a result of strength tests that fine-grained clay minerals negatively affect the strength performance in the short and long term and it was obtained that it would be beneficial to subject a sulfurous mine waste with high clay content to preliminary preparation processes in order to be usable in paste backfill.