The disturbance during hardening will cause mortar cracks and aggregate displacement, which can affect the later strength and durability. Using shaking table to simulate engineering disturbance, the deterioration rule of early disturbed concrete under dry wet cycle was investigated systematically by means of ultrasonic and scanning electron microscopy in order to analyze the effect of the disturbance of hardening period on the sulfate resistance of concrete. The mechanism of concrete damage deterioration was discussed. Results show that the disturbance closer to initial setting (the penetration resistance is 3.5 MPa to 11.5 MPa) and final setting (the penetration resistance is 19.5 MPa to 28.0 MPa) has smaller effect on concrete. The change rule of weight and relative dynamic elastic modulus is consistent with that of the non-disturbed concrete. The disturbance of hardening medium (the penetration resistance is 11.5 MPa to 19.5 MPa) has obvious influence on concrete. The compressive strength loss reaches above 14% and the flexural strength loss is more than 20%; in the course of corrosion, the weight of concrete decreases obviously after 90 cycles. The relative dynamic modulus decreases sharply after 130 cycle, and reaches 0.60 after the 250 cycle. The relative dynamic modulus of the concrete is still about 0.90. The results of SEM show that the internal micro cracks of the disturbed concrete increase and the structural compactness becomes worse, and the disturbance accelerates the deterioration of concrete under sulfate attack.
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