The application of a pseudodynamic technique to yield a shock response from an impulse might encounter a difficulty caused by a significant load discontinuity at the end of the impulse since this load discontinuity at the end of an impulse will result in an extra impulse and then an extra amplitude distortion. This extra impulse is linearly proportional to the step size and thus it is natural to consider the use of a very small time step for a whole pseudodynamic test to overcome the difficulty. However, a series of computer simulations reveal that this approach might not be feasible. This is because that the use of a small time step will lead to a very small displacement increment and it may be contaminated by experimental errors as its magnitude is less than or close to the magnitude of the experimental errors. Thus, an inaccurate test result is obtained. A technique is proposed to overcome this difficulty. This novel technique is to perform a single small time step immediately upon the termination of the applied impulse while the other time steps are conducted by using the time step determined from general considerations. This single small time step will not lead to a significant error propagation problem since only this time step is performed by using a very small step size for a complete pseudodynamic test. The feasibility of this technique was confirmed by a series of pseudodynamic tests.

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