The method uses laser speckle technique to record the shift amount of speckle patterns due to micro wedge angles, and thus micro wedge cangles of the test piece are induced.

它利用激光散斑技术，记录了由于微小楔角引起的散斑位移量的散斑图，由此导出被测试件的微小楔角。这种方法具有光路简单、非接触、精度高等特点。

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Using traditional interferometric method, as the germanium material is too soft to process, the surface form of the test piece may not meet the requirement for the measurement.

运用传统的干涉法检验光学材料的折射率均匀性时，由于锗晶体太软，表面不易加工，其表面面形难以满足测试要求。

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The first frequency method of estimating the fatigue serviceability on small and medium span railway concrete bridge is discussed in this paper through three piece test beam under fatigue load.

通过三片模拟梁试验实测结果，探讨了基频法评估铁路桥梁疲劳使用性能的可行性。

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