| 摘要 |
<p>Self-levelling, high performance concrete shows, over a period of 28 days, a compression resistance of at least 150MPa; a modulus of elasticity of at least 60Gpa; and, after 40 hours, a compression resistance of at least 100MPa. Self-levelling, high performance concrete which shows, over a period of 28 days, a compression resistance of at least 150MPa; a modulus of elasticity of at least 60Gpa; and, after 40 hours, a compression resistance of at least 100MP comprises: a cement of grade size corresponding to a diameter up to around 7 mu m, preferably = 3-7 mu m; mixture of calcinated bauxite sands of varying grade sizes, the finest having grade size less than 1mm and the roughest having grade size less than 10mm; silica ash in which 40% particles have one dimension less than 1 mu m and a diameter in the region of 1 mu m; anti-foaming agent; superplastifier for water reduction; optional fibres; and water; cement, sands and ash having between 3 and 5 different grade sizes, the ratio of the harmonic mean grade size to the next one up being about 10. Independent claims are also included for method for preparing concrete, dry concrete mixture; and use of concrete in making prefabricated parts such as posts and girders, pre-constrained parts for various structural developments.</p> |
