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Aeolian sand is mainly distributed in arid and rainless desert areas. It is a special soil with loose structure, fine and uniform particles, poor self-stability and not easy to compact. For discussion The law of microbial solidification of large-volume aeolian sand, the use of microbial induced calcium carbonate precipitation technology, the use of Bacillus pasteurianus, the microbial addition to the aeolian sand column in a saturated state In the solid test, the bacterial concentration at different depths in the sand column as well as the bacterial adsorption capacity, enzyme activity, urea concentration and other indicators were determined. At the same time, the dryness of the cured samples at different depths was analyzed. The changing law of density, unconfined compressive strength and calcium carbonate content. The test results show that the best standing time of the bacteria in the sand column is 4 hours, and the best standing time of the cementing liquid in the sand column is 4 hours. Set the time to 24h. By pouring the aeolian sand with Bacillus pasteurianus and cementitious liquid, calcium carbonate crystals can be formed between the aeolian sand particles, thereby bonding the sand particles together. To form a whole with a certain strength. The unconfined compressive strength of solidified aeolian sand is between 0.43 and 7.13 MPa. Microbial-induced calcium carbonate precipitation technology to solidify aeolian sand The effective depth is 0.2 to 0.7 m. The dry density, unconfined compressive strength and calcium carbonate content at different positions of the solidified sand column have similar changes with depth, and they all increase first and then decrease. The peak is reached at about 0.4 m. Therefore, the use of microbial induced calcium carbonate precipitation technology can effectively reinforce aeolian sand in deserts, and can significantly improve the engineering properties of aeolian sand. [ABSTRACT FROM AUTHOR]