| 摘要 |
1312904 Anchoring bolts STRATA MINING PATENTS Ltd 8 Feb 1972 [16 Feb 1971 10 May 1971] 4749/71 and 14040/71 Heading F2H An anchor bolt is set in a bore in a structure by inserting into the bore water and a quantity of particulate material consisting at least partly of a gypsum and aluminous cement mixture in which the gypsum content is between 30 and 70% by weight, in a manner keeping the water and particulate material apart, preferably by using separate capsules, and then inserting and rotating the bolt to mix the water and particulate material, the mixture setting to anchor the bolt in the bore. An inert bulking agent such as fly ash, wood flour, or foamed polystyrene may additionally be present so that the bolt can be set underwater. A gelling agent such as an alginate, polyvinyl alcohol, polyacrylic acid, carboxy methyl cellulose, or a metallic soap may be added to the water to increase its viscosity so that the method can be used to set a bolt in a ceiling. Freezing or corrosion inhibitors may also be added to the water, particularly if an iron or steel bolt is used. The ratio by volume of particulate material to water is between 1 : 1 and 5 : 1, preferably between 2 : 1 and 4 : 1. The water and particulate material are inserted into the bore in separate capsules which may be made of a brittle material such as unplasticized polystyrene. The capsules may be joined to form a composite container in which case the water capsule may have a flexible plastics wall and be contained within the capsule of particulate material, the latter being made of a water-soluble substance such as polyvinyl alcohol. Alternatively the two capsules in the composite container may be positioned side-byside, the container having a cylindrical shape. |
