Abstract:In order to study the effect of different silica powder contents on the frost resistance performance of hydraulic concrete, hydraulic concrete test blocks were prepared with Portland cement, crushed stone, medium sand, water reducing agent and silica powder as raw materials. Freeze-thaw cycle tests, uniaxial compression tests and dynamic elastic modulus tests were carried out on the test blocks with 0%, 2.5%, 5%, 7.5% and 10% silica powder contents. The results show that the compressive strength of the hydraulic concrete test blocks decreases with the increase in the number of freeze-thaw cycles. Adding silica powder can effectively improve the frost resistance of hydraulic concrete, but the effect will be affected if the content of silica powder is too high or too low. When the silicon powder content is 5%, the frost resistance effect is the best. Under 60 freeze-thaw cycles, the compressive strength is increased by 15.1%, the mass loss rate is decreased by 0.17%, and the relative dynamic elastic modulus is increased by 0.014%.