Effect of SAP internal curing on mechanical properties and durability of semi-rigid subgrade in aeolian sand

In order to improve the anti-cracking performance of the semi-rigid base and reduce the maintenance cost of the semi-rigid base, this paper adopts the orthogonal test method to study the influences of the multi-dimensional cementitious composite system, the type of SAP, the dosage of SAP and additional water intake of SAP on the mechanical properties and the dry shrinkage performance of the semi-rigid base of the aeolian sand. The test data of strength index and shrinkage index were analysed by extreme difference analysis and analysis of variance respectively, and the results showed that when the cement: fly ash is 1:4, the cementitious material: aggregate is 17:83, the aeolian sand replaces 12 % of fine aggregates, the SAP type is composite, the SAP dosage is 0.05 %, and the additional water intake of SAP is 20 times in order to get the optimal internal curingprogramme, and also provides a theoretical basis for the further application of aeolian sand in semi-rigid subgrade.