12.2.2 Optimization strategy

Methodologies used for back analysis can be classified into two groups，i.e.，（1）deterministic methods and（2）probabilistic methods.In a deterministic method，analysis model is usually believed or assumed accurate，and the purpose of back analysis is to find a set of parameters fitting the observation.In a probabilistic back analysis，however，it is recognized that the analysis model may not be perfectly accurate and numerous combinations of parameters may result in the same response.Table 12.1 lists several optimization techniques widely used in geotechnical engineering and some of them will be introduced later.

Table 12.1 Optimization techniques used in geotechnical engineering