Reinforced Soil Retaining Wall, Reliability Analysis And Decision-making

The research history and newest development of reinforced retaining wall and reliability of geotechnical engineering are simply discussed in the first chapter.In the second chapter, the basic principles of reliability and common methods of calculation, First Order Second Moment Method, Monte-Carlo Method, Optimization Method and Iconography Method etc, are introduced. The Monte-Carlo Method as well as Optimization Method are programmed by Matlab language. The more practical and easy Iconography Method is presented. An example shows the calculation method results are quite near.In the third chapter, the origin of uncertainty and Random field model as well as the probability characteristics of soil parameters, including self-correlation and cross-correlation, are introduced. The coefficients of cross-correlation of several important parameters are calculated according to statistical data.The probability characteristic of parameters in the reinforced retaining wall are analyzed in the forth chapter. The reliabilities, including anti-breaking and anti-pulling of geotexile, anti-overturning and anti-sliding of the wall, and the base bearing capacity are analyzed with an example of reinforced retaining wall. The influences of variation of soil parameters to the safety index are discussed as well. Two design cases are compared.The influence of cross-correlations among three pairs of soil parameters on the reliability of reinforced retaining wall under various destructive models is discussed in this chapter. The three pairs of soil parameters are (1) the cohesion and friction angle, (2) the friction coefficient between fill and geotexile, and friction angle, and (3) the friction coefficient between fill and ground, and friction angle.The decision making of the reinforced retaining wall is carried on based on reliability theory by taking the minimum cost as the target. The best plan is drawn by changing the parameters in several plans. And the safety and efficiency are balanced in the plan.Some conclusions are drawn at the end of thesis, and they can supply some scientific basements for the reliability analysis and decision making of reinforced retaining wall.