| 摘要 |
<p>A method of making a hollow article is disclosed, the method comprising inflating a hollow former which has the shape of the article to be produced. The outer surface of the former comprises a fabric woven or knited from a yarn which includes a core and a multitude of staple fibres forming a layer which envelopes the core and provides an extended surface area and interstical spaces for infiltration by cement fines and hydrates, the staple fibres being spun around the core and attached to the core, the staple fibres having sufficient freedom of radial movement to provide said spaces and permit ingress of cement fines and the formation of its hydrates in said spaces. Cementitious mix then applied to the fabric to create an outer cementitious layer. Several such layers of fabric and mix can be applied to build a wall of the requisite thickness. The hollow former can be a bladder to the outer surface of which the fabric is applied. Alternatively the fabric can be laminated to an air impervious plastic film, and the former produced from said laminate.</p> |
