Portable microbial induction calcium carbonate precipitation kit and application thereof in repairing of early crack of pavement base course

Abstract

The invention relates to a portable microbial induction calcium carbonate precipitation kit and application thereof in repairing of an early crack of a pavement base course. The portable microbial induction calcium carbonate precipitation kit comprises a first component, i.e., urease generation bacterial solution, a second component, i.e., urea, a third component, i.e., calcium source and a fourth component including peptone, yeast extracts and sodium chloride, wherein each component is individually packaged. When the portable microbial induction calcium carbonate precipitation kit is used, each component is prepared into a solution in field, and the solutions are mixed according to a specific sequence and are added into a crack to be repaired. The portable microbial induction calcium carbonate precipitation kit can be conveniently carried, has long preservation time, and can be suitable for various construction environments.Bacterial strains in the kit are separated and screened from soil, in a repairing process, no secondary pollution is caused for the environment, and cost is low. More importantly, the screened bacterial strain has a high utilization rate and does not need to be directly mixed with cement mortar or a cement base body, so that the problems that a great quantity of cultures dies or activity is lowered and the like since the bacterial strain needs to be directly mixed with cement mortar or the cement base body can be avoided, and the crack repairing capacity of the portable microbial induction calcium carbonate precipitation kit is guaranteed to a maximum extent.

Description

technical field [0001] The invention relates to the technical fields of biochemistry and construction, in particular to a portable microbial-induced calcium carbonate precipitation kit and its application in repairing early cracks in pavement bases. Background technique [0002] Cement-stabilized macadam is a typical pavement base material, which mainly consists of aggregate and mortar volume. The aggregate is graded crushed stone and the mortar volume includes water and cementitious material consisting of cement and admixture. Cement-stabilized macadam has good plate properties, water stability and frost resistance, but it often causes shrinkage cracks due to moisture changes. In addition, due to the influence of external environmental factors (such as temperature and external load), water-stable materials will produce micro-cracks and damages to varying degrees. If effective measures cannot be taken in time to repair in the early stage, it will not only affect the appear...

AI Technical Summary

Problems solved by technology

Cement-stabilized macadam has good plate properties, water stability and frost resistance, but often causes shrinkage cracks due to moisture changes

In addition, due to the influence of external environmental factors (such as temperature and external loads), water-stable materials will produce micro-cracks and damage to varying degrees

If effective measures cannot be taken in the early stage to repair, it will not only affect the appearance in the later stage, but also reduce the bearing capacity and durability of the base layer

Enlarged cracks may even affect the safety of the pavement structure, resulting in hidden dangers or accidents

[0003] Most of the existing repair materials (such as cement mortar, epoxy resin or modified polymer materials, etc.) generally have the following problems: (1) The chemical composition of the repair materials contains toxic substances, which will cause material pollution and may cause environmental pollution. Harmful; (2) Most of the repair materials are easy to age, resulting in small cracks and damages again, requiring repeated repairs; (3) The compatibility of repair materials and cement materials is poor, the fluidity is not good, and the particles are too large to completely penetrate the early stage (4) Most of the repair materials are directly added to the cement mortar or cement matrix, which is not concentrated enough in the cracks, and the repair effect needs to be further improved

However, the interior of the cement material is relatively dense and highly alkaline, the survival rate and activity of microorganisms in the repair agent directly mixed will be significantly reduced, and the microorganisms are relatively dispersed and the utilization rate is low, resulting in a greatly reduced repair effect

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