Cement-base material with good movability and high intensity, and method of manufacturing the same

Abstract

The invention provides a cement-based material with good liquidity and high intensity and a preparation method thereof. The compositions by mass percentage of the cement-based material are: 10.8 to 18.9 percent of cement, 8.1 to 16.2 percent of composite industrial residue, 0.6 to 0.65 percent of efficient additive, 32.3 to 34.1 percent of fine aggregate, 32.3 to 34.1 percent of high intensity coarse aggregate and 2.7 to 7.8 percent of short and thin steel fiber. In the cement-based material, the homemade short and thin steel fiber and the additive with a water reducing rate more than 40 percent are used, the cement is replaced by 30 to 60 percent of the composite industrial residue, the grind sand is replaced by common sand, and the high intensity coarse aggregate is blended in. In the condition of standard curing or natural curing, the superior performance cement-based material with a compressive resistance of between 150 and 200MPa and a breaking strength of between 20 and 70MPa is prepared. The preparation method greatly lowers the cost of raw materials, simplifies the production technology, uses a large amount of industrial residue, and provides broad prospect for the large-scale popularization and application of the superior performance cement-based material.

Description

technical field [0001] The invention belongs to the technical field of building materials, in particular to an ultra-high performance cement-based material and a preparation method thereof, and is mainly used in civil engineering fields such as construction engineering, roads, and bridges. Background technique [0002] At present, the ultra-high-performance cement-based material with a strength level of 150-200 MPa is publicly reported in the world. It is a RPC material (Reactive Powder Concrete) developed by a research team headed by French scientist Pierre Richard in the 1990s. Its preparation principles mainly include: (1) Remove coarse aggregate, use ground quartz sand and control the fineness of sand within 600μm; (2) Add superplasticizer to reduce water-cement ratio, optimize particle gradation and before and during solidification Apply pressure to the cement-based composite material to increase the compactness; (3) improve the microstructure of the concrete by heat tr...

AI Technical Summary

Problems solved by technology

[0003] (1) The preparation of RPC uses ground quartz sand instead of ordinary coarse and fine aggregates, and the maximum particle size is controlled below 600 μm. In fact, this kind of concrete is not concrete, but fine-grained mortar, and the energy consumption of the quartz sand grinding process is very large. , the cost is very high; (2) The types of active mineral admixtures are relatively single, and most of them only use expensive silica fume, and the amount is as high as 25% or more (replacing the amount of cement); (3) The amount of ultrafine metal fibers is large and the price is low. It is high and needs to be imported; (4) In order to ensure the full development of strength, it is necessary to apply pressure during the cement solidification process and use 90 ° C hot water or 200 ° C above pressure steam curing. The process is complicated and the maintenance energy consumption is high. It is suitable for the product factory. It is not convenient for on-site pouring for production; (5) RPC does not use coarse aggregate, so that the powdery cementing material (cement + silica fume + quartz powder) is as high as 1200kg / m 3 Above, the cost is as high as $1,000 and above

The above shortcomings seriously limit the large-scale application of RPC materials in practical engineering.