3D Concrete Printing (3DCP) process is rapidly developing worldwide, showing its ability to construct large-scale components or even a building. However, the current 3DCP process has found it hard to manufacture architectural components with detailed ornamentations and features on their surface due to the Fused Deposition Modelling (FDM) manner that generates fixed-width thick filaments. This paper introduces a novel Volume-Forming 3D Concrete Printing (VF3DCP) method applying a variable-diameter square nozzle to manufacture architectural ornaments. The VF3DCP method directly fabricates a variable cross-section volume during one-time work instead of an FDM accumulation process. A VF3DCP extrusion kit prototype containing a steering module and a nozzle-varying module and a particular adaptive tool path planning algorithm are developed. Functional relationships of four key process parameters for a trial material, including nozzle diameter, nozzle moving velocity, material extrusion rate and tool path curvature radius, are fitted by process tests. Finally, a case study into a VF3DCP architectural carve pattern is conducted, which shows the potential of the proposed method in manufacturing architectural ornaments.

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To build a permanently inhabited base on the Moon is a vitally important step to developing deep space exploration and lunar colonization. Therefore, indigenous materials become a significant requirement for lunar construction as transporting the construction materials from Earth is extremely expensive. Fortunately, construction materials can be fabricated by utilizing in-situ materials on the Moon. Dry mix autoclaving is a feasible process for lunar construction material manufacture. In this study, the influence of calcareous material ratio, LRS fineness and briquetting pressure on mechanical property was discussed to estimating the most appropriate technological parameter. The strength forming mechanism was expounded by the investigation of hydration products. The result shows that introducing appropriate amount of high-activity calcium materials can improve the strength and promote the generation of target hydration products. Meanwhile, the increasing of LRS fineness resulted in weakening of compressive strength which may ascribe to the decreasing compactness caused by the trapped gas during forming process with finer particles. The increment of briquetting pressure enhanced compressive strength in a certain range. However, it should be implemented after comprehensive consideration of the enhancing effect. This research provides support for preparation of autoclaved lunar construction materials in the near future.