Abstract: Based on the problem of insufficient excitation force caused by the excitation of the exciter in the forced vibration excitation test of the traditional ground, a method is proposed to increase the exciting disturbing force by using the parallel double multiplying force electromagnetic excited vibration. To this end, we first analyzed the shortcomings of the common mechanical vibration exciter, puts forward the design and improvement methods of parallel double double force electromagnetic vibration exciter, and then combined with the incentive effect of the difference between the actual project test data comparison,find out the different frequency of driving function between the current and the amplitude frequency response, finally through different types of foundation the actual test results show that the parallel double double force electromagnetic vibrator can not only satisfy the curve of amplitude and frequency characteristics of natural foundation soil with low frequency requirements can meet the requirements of the rock foundation and pile foundation block based high frequency amplitude frequency characteristic curve,the test of frequency response curve the true frequency response in a wide range of threshold, but also improve the mechanical vibration force and low bandwidth limit is not suitable for rock foundation and the pile body block vibration test based problem that parallel double double force electromagnetic vibrator can be used force of foundation soil forced vibration test, further verify the forced vibration tests parallel double double force generated electromagnetic vibration exciter for double force pile block foundation is feasible.