Development of cementitious material by incorporating fine waste materials for testing in newly developed portable concrete 3D printer
摘要
The sustainability requirements in the construction industry necessitate the development of cementitious materials by incorporating local by-products and waste materials. The present study deals with developing cementitious additives using local materials and fine wastes incorporation to test in a locally fabricated portable concrete 3D printer with a bed size of 1 × 1 × 0.5 m. The printer is capable of motion control in 3D space and an accurate material dispensing system to test the trials of different mixes. The experimental plan to develop the local cementitious material includes the selection of optimum ratios of the materials satisfying the slump, water/cement ratio, buildability, setting time, compressive strength, durability and the bond strength of crafted layers. The optimal percentage of fine wastes (reservoir sediment and marble waste) incorporation in the mixes is experimentally determined to control shrinkage, buildability and crafting quality. The durability of hardened mixes is studied by exposing them to wet/dry and freeze/thaw cycles and measuring their resistance to abrasion. The incorporation of 3–4% fine sediments with local commercial sand and white cement as a binder shows potential to be used as cementitious material in 3D crafting and achieving compressive strength more than 25 MPa, as well as achieving buildability and durability. The experiments demonstrated that the locally developed mix is suitable cementitious materials for crafting concrete for prototyping and non-loadbearing constructions.