The copper-nickel alloys after special annealing treating possess the properties of permanent resistance change when it experienced to fatigue loading.It can be used as fatigue sensor material.However

the working strain for the designed S/N is so high

a strain multiplier is designed.It can greatly promote the sensor’s sensitivity

so that it can satisfy the asking of health monitoring for engineering structure

which works usually in relative low alternating strain and long life.Through experiment the temperature effect and the amplifier coefficient of the sensors in different deformation state are also researched.Modifier formulas of temperature output and amplifier coefficient is obtained.The design sensor can satisfy the demand for fatigue monitoring of large engineering structure

and it has an advantage over other methods in accuracy

economic and efficiency.