Variable Research on Engineering Characteristics of Soybean Urease Reinforced Sand

In this study, based on soybean urease and standard sand, the unconfined compressive strength test and permeability test of four variables of urease concentration, urea concentration, calcium chloride concentration and sodium alginate content under different combinations of values were carried out, and the range analysis and variance analysis of test data were carried out. On this basis, the coupling model of unconfined compressive strength and permeability coefficient of soybean urease reinforced sand was established based on four test variables. It was found that the engineering characteristics of soybean urease reinforced sand were significantly affected by the combination of variable values. The maximum value of unconfined compressive strength under the test combination condition was 6.5 times of the minimum value, and the minimum value of permeability coefficient was only 1/4 of the maximum value. The primary and secondary order of influence variables of unconfined compressive strength was: urea concentration > calcium chloride concentration > urease concentration > sodium alginate content, and the primary and secondary order of influence variables of permeability coefficient was: urea concentration > calcium chloride concentration > sodium alginate content > urease concentration. The influence of urea concentration on unconfined compressive strength and permeability coefficient was obvious, and the influence of the other three variables was not obvious. In addition, it was confirmed that the established coupling model of unconfined compressive strength and permeability coefficient of soybean urease reinforced sand had high correlation coefficient and significant linear regression, which can be used for subsequent research and engineering application.