Concrete with strength grade of C70 for section steel concrete composite structure

Abstract

The invention discloses a concrete with strength grade of C70 for composite structure of steel reinforced concrete. Mixed proportion of the concrete is that cement: coarse: aggregate: fine aggregate: water: effective water reducer: silica fume: fly ash is 400:576:1224:148:8:30:120. Component unit is Kg / m3. The concrete is in good mechanical properties (comprising strength, plastic and bond behavior between section steel and concrete), excellent in working performance, good in durability and relatively lower in cost, and is suitable for the composite structure of steel reinforced concrete. Theuse of the concrete reduces construction procedures, saves steel, improves construction efficiency and has remarkable economic benefit.

Description

Concrete used for steel-concrete composite structures with a strength grade of C70 The present invention is a divisional application with the filing date: March 22, 2006, the application number: 200610041959.5, and the title of the invention: "a concrete for steel-concrete composite structures" technical field The invention relates to a concrete, in particular to a concrete with a strength grade of C70 for a steel-concrete composite structure. Background technique The steel high-strength high-performance concrete composite structure is the application of new high-tech concrete in the steel-steel concrete (SRC) composite structure. Among them, steel-concrete composite structure (SRC structure for short) is a main form of steel-concrete composite structure. Tall and supertall buildings in structural and seismic zones. Compared with the steel structure, the SRC structure can save a lot of steel, increase the section rigidity, overcome the disadvantages of the steel structu...

AI Technical Summary

Problems solved by technology

At present, there are generally two ways to deal with the bond-slip problem between steel and concrete in engineering design: one is to add shear connectors on the surface of the component, which will inevitably cause inconvenience in construction and increase the cost; the other is to Reduce the bearing capacity of components to consider the influence of bond slip, so there must be uneconomical factors

On the other hand, in the design of engineering structures, there is a phenomenon of emphasizing strength and ignoring durability. There have been many problems with the safety and durability of concrete structures during use at home and abroad.

Some concrete structures completely lose their function and bearing capacity due to alkali-aggregate reaction, chloride ion erosion and other reasons when they are used for less than half of the design life. Some projects even collapse partially or overall, causing casualties or damage to building facilities.