介绍了协方差分解技术和谱代替法两种模拟随机场的方法，对两种方法的优缺点作了详细的论述，并探讨将谱代替法应用于岩土工程可靠度计算的方法。将协方差分解技术和谱代替法分别应用于蒙特卡罗随机有限元法，计算了一个堤坡的局部失效概率。经比较认为，谱代替法是模拟土性参数随机场的一种有效的方法。

Two methods for random field simulation， i.e.， covariance matrix decomposition method and spectral representation method (SRM) areintroduced, their merits and disadvetoges are presented and commented in detail. An example is given to show the use of these two methods in the failure probability calculation of an embankment. The calculation result shows that the SRM needs relatively few steps of simulaton and is much more efficient than covariance matrix decomposition method.