The fiber volume ratio of ordinary steel fiber reinforced concrete is between 1% and 2%. Compared with ordinary concrete, the tensile strength is increased by 40% to 80%, the flexural strength is increased by 60% to 120%, and the shear strength is increased by 50% to 100%. %, the increase in compressive strength is small, generally between 0-25%, but the compressive toughness is greatly improved.
The surface of steel fiber concrete should be wet for not less than 7d, the longer the better, and the surface should be covered with wet straw bags or maintenance materials. When maintaining the steel fiber conversion beam, avoid contact with wind, sun, rainwater, etc., and the construction beam body should be sealed against wind and rain. For steel fiber conversion beams, the demoulding time should be strictly controlled after reaching the concrete 28d strength specified in the specification. In case of winter construction, antifreeze measures can be taken according to conventional methods.
Dosage inspection
(1) The amount of steel fiber is sampled and inspected at the concrete pouring site. Each work shift is inspected at least twice. Three groups of samples are taken each time, and each group of samples is 1OL.
(2) Through the water washing method, the steel fibers are washed out of the concrete, dried and weighed. The deviation of the steel fiber content of a single sample shall not exceed 20% of the proportion of the proportion, and the average value of the steel fiber content of every three samples above The deviation shall not exceed 5% of the proportioning content.
