The invention belongs to the technical field of concrete, and particularly relates to
colored black
iron powder micro-expansion self-compaction bare concrete which comprises
cement,
coal ash, fibers, an expanding agent, fine aggregate, coarse aggregate, black
iron powder, an additive and water, the fine aggregate is two-zone shaping medium sand, the coarse aggregate is shaping pebbles, the particle size of the pebbles is 5-20 mm, the black
iron powder is continuously graded, and the additive is water. The admixture comprises the following raw materials: a water
reducing agent, a
viscosity reducer, a
slump retaining agent, a workability improving agent, a
retarder and a defoaming agent, and the
doping amount of the admixture is 2.2%-2.7% of the weight part of the cementing material (
cement,
fly ash and the expanding agent). The invention further provides a construction method of the
colored black iron
powder micro-expansion self-compaction bare concrete. The method can reduce and even avoid surface defects of concrete, particularly controls bubbles and colors on the surface of the concrete, controls shrinkage cracks of the bare concrete, has
crack resistance, is low in hydration heat, and avoids
temperature difference cracks of the bare concrete in the early stage.