Experimental Study on Solidifying Aeolian Sand Filled in the Narrow Space of Distress Culverts

A variety of distress have appeared in culvert structure in permafrost regions of China, which seriously affects safety of the structure in use. In view of the damage of reinforced concrete slab culvert structure along a highway in Qinghai Province, this paper presented a strengthening method for culvert structure. The corrugated steel pipe is placed in the reinforced concrete slab culvert, and the void between the original slab culvert and the corrugated steel pipe is filled with solidified aeolian sand, thus forming a whole and sharing the load. The method mainly depends on the solidifying effect of aeolian sand. This paper mainly studied the solidifying and strengthening effect of three inorganic binders (cement, lime, lime and fly ash) on aeolian sand. By standard heavy compaction test and California Bearing Ratio (CBR) experiment, the influence of water and salt content on compactness characteristics and CBR value of solidified aeolian sand are studied, respectively. The test results show that the solidified aeolian sand can meet the requirements of relevant specifications of subgrade backfill and the culvert strengthening method in terms of compactness characteristics and mechanical properties.