Sprayed concrete with microorganism crack self-repairing capacity and preparation method of sprayed concrete

Abstract

The invention discloses sprayed concrete with microorganism crack self-repairing capacity and a preparation method of the sprayed concrete. The sprayed concrete is prepared from components as follows:self-repairing particles carrying a microorganism repair agent and nutrients, cement, pebbles, sand, silica fume, water, polypropylene fibers, a sodium aluminate liquid accelerator and a polycarboxylate superplasticizer. The microorganism with mineralization and sedimentation characteristics is taken as the crack repair agent of the sprayed concrete, and expanded perlite or flyash pottery sand with high porosity is taken as a carrier of the repair agent; the carrier is coated with the nutrients and is isolated from a cement-based material by an isolating layer. The concrete cracks are repaired by calcium carbonate precipitate produced by the microorganism repair agent in a metabolism process, and the crack self-repairing capacity of the sprayed concrete in the service is improved, so thatimpervious performance and durability of the sprayed concrete are improved. The sprayed concrete with crack self-repairing capacity as a sprayed concrete material with crack self-diagnosis and self-repairing functions has great research value and application potential.

Description

technical field [0001] The invention relates to the field of concrete materials, in particular to microbial crack self-repairing shotcrete and a preparation method thereof. Background technique [0002] Shotcrete is made by spraying machinery, using compressed air or other power, transporting the mixture in a certain proportion through pipelines and spraying it on the surface to be sprayed (rock wall, formwork, old building) at high speed to solidify and harden of a concrete. The essential difference between sprayed concrete and ordinary concrete is that its construction method is special. It uses a concrete sprayer to spray directly to the construction site. It does not need to support the formwork and only relies on adding accelerators to the concrete to harden the concrete in a short time. The rock or structure being blasted is strengthened and protected. It is precisely because of the advantages of simple construction, unlimited construction site, flexible maneuverabil...

AI Technical Summary

Problems solved by technology

At present, the main repair methods for shotcrete cracks are post-event repair or regular repair. However, shotcrete is mainly used in tunnel engineering, underground engineering and other engineering fields, which makes the repair process of shotcrete cracks more complicated, and this passive and planned repair Most of the methods are aimed at cracks visible to the naked eye

In addition, the actual shotcrete is mostly in the working state with cracks, that is, there are many microcracks inside the shotcrete. Due to the limitations of the current detection technology, it is still difficult to diagnose and repair these microcracks.