Vibration Failure of Young Low-Temperature Concrete Shaft Linings Caused by Blasting Excavation

Table 2

Mechanical parameters of C65 concrete test blocks of different ages.

Age (d)	1	2	3	3.5	6	7	8.5	11	13.5	14	16	18.5	28
Uniaxial compressive strength (MPa)	15.1	26	34.3	37.1	50.7	54.4	58.7	63	65.1	65.3	66.7	68.1	72.7
Elastic modulus (GPa)	22	26.5	30	30.4	33.7	34	34.9	35.5	35.8	35.8	35.9	36.1	36.3
Longitudinal wave velocity (m/s)	3125	3333	3571	3587	3808	3846	3925	4010	4073	4083	4123	4163	4267
Shear modulus (GPa)	9.2	11	12.5	12.7	14	14.2	14.5	14.8	14.9	14.9	15	15	15.1