Steel fiber reinforced concrete floor construction abstract(一）

1.Steel fiber reinforced concrete floor construction abstract(一）

       Steel fiber reinforced concrete as a new composite material, it has become a concrete direction of scientific development, and its good crack resistance, flexural toughness, flexural strength and other properties, is widely used in the construction field. Steel fiber floor construction, the key is to control the flatness of the floor and preventing cracking. Meanwhile, in the construction of grass-roots change around the floor, filling, gravel cushion rolling, steel fibers stirring and  vibrators, etc., to strengthen the dynamic management.
In Baosteel Special Steel titanium-nickel special metal sheet transformation project, its Floor extensively use of steel fiber reinforced concrete with a total area of about 20,000 square meters, the floor base is 500mm thick, replacement of gravel base layer , structural layer of 200mm steel fiber reinforced concrete. Low-carbon cold drawn steel fibers with hooked ends used in the plant, fiber length 50mm, diameter of 0.9mm, an aspect ratio of 56, a tensile strength ≥ 600 MPa, steel fiber dosage of 25Kg / m3, from now completion of construction steel fiber floor, the surface smooth, clean, no hollowing, cracking phenomenon, praise the construction units and related departments.
 
2, characteristics and keys analysis of the project

     2.1 Location is in Baosteel special steel plant, since the position of the plant located in the old factory building demolition on the ground, the surface soil is loose, mingled a lot of mud, brick, oil and other construction waste, the design and quality control departments must be identified of replacement. Excavation site average depth of about 500mm, under prime soil compaction. How to ensure the grassroots floor backfill soil compaction after stratification meet the design requirements, to prevent uneven settlement, it is a focus of flooring construction.

      2.2 Controlling of the concrete surface levelness floor surface :flatness tolerance requirements within 3mm, levelness high requirements, how to control the surface flatness is another focus of construction.

     2.3 To prevent cracks in the ground floor ruled is based on the performance of steel fiber reinforced concrete floor to determine the true floor (expansion) joints and false (reduced) seam setting, and each real seam is setted each 30m t, per 6m setting a false seam. The above of the false seam, the steel rebar is disconnected, the below of the false seam, the steel reabr  can be opened. Seam width 8mm, deep seam 70mm, filled with polystyrene foam board inner seam sealing, top with 8mm ointment;  The steel bar in the up layer and down layer of real seam are all  turned off, slit width 30mm, filled with polystyrene foam board inner seam, top with 30mm ointment closure.