Application of a Stochastic Elasto-Plastic Model with First-Order Spectral Expansion to Soil

2018 ◽  
Vol 12 (04) ◽  
pp. 1841006
Author(s):  
Kazumoto Haba ◽  
Wataru Hotta ◽  
Akihito Hata ◽  
Muneo Hori

The efficient treatment of uncertainties in soil properties is essential for seismic probabilistic risk assessment. Recently, we developed a stochastic elasto-plastic model based on the first-order spectral expansion of the stochastic behavior. This new treatment is applied to elasto-plastic soil with uncertain material properties. A numerical experiment is performed to evaluate the probabilistic constitutive relation. The probabilistic stress–strain relation of soil is simulated successfully in agreement with the standard Monte-Carlo simulation. In addition, some characteristics of the probabilistic elasto-plastic soil are studied.

2012 ◽  
Vol 60 (2) ◽  
pp. 205-213
Author(s):  
K. Dems ◽  
Z. Mróz

Abstract. An elastic structure subjected to thermal and mechanical loading with prescribed external boundary and varying internal interface is considered. The different thermal and mechanical nature of this interface is discussed, since the interface form and its properties affect strongly the structural response. The first-order sensitivities of an arbitrary thermal and mechanical behavioral functional with respect to shape and material properties of the interface are derived using the direct or adjoint approaches. Next the relevant optimality conditions are formulated. Some examples illustrate the applicability of proposed approach to control the structural response due to applied thermal and mechanical loads.


2021 ◽  
Vol 7 ◽  
pp. 1954-1961
Author(s):  
Andrea Colantoni ◽  
Mauro Villarini ◽  
Danilo Monarca ◽  
Maurizio Carlini ◽  
Enrico Maria Mosconi ◽  
...  

2016 ◽  
Vol 23 (3) ◽  
pp. 97-105
Author(s):  
Deyu He ◽  
Niaoqing Hu ◽  
Lei Hu ◽  
Ling Chen ◽  
YiPing Guo ◽  
...  

Abstract Assessing the risks of steering system faults in underwater vehicles is a human-machine-environment (HME) systematic safety field that studies faults in the steering system itself, the driver’s human reliability (HR) and various environmental conditions. This paper proposed a fault risk assessment method for an underwater vehicle steering system based on virtual prototyping and Monte Carlo simulation. A virtual steering system prototype was established and validated to rectify a lack of historic fault data. Fault injection and simulation were conducted to acquire fault simulation data. A Monte Carlo simulation was adopted that integrated randomness due to the human operator and environment. Randomness and uncertainty of the human, machine and environment were integrated in the method to obtain a probabilistic risk indicator. To verify the proposed method, a case of stuck rudder fault (SRF) risk assessment was studied. This method may provide a novel solution for fault risk assessment of a vehicle or other general HME system.


2011 ◽  
Vol 356-360 ◽  
pp. 1786-1789 ◽  
Author(s):  
Yi Hua Liu ◽  
Fu Bin Tang ◽  
Guo Nian Zhu

Anilofos is the organophosphorus herbicide widely used in China. However, little is known on the processes governing the environmental fate of anilofos in soils and its environmental risk for groundwater. Several environmental fate studies were performed concerning the degradation, sorption, photolysis and mobility of anilofos in soils. The degradation of anilofos in three Chinese soil samples followed first-order kinetics, with half-lives between 64.2 d-161.2 d. The adsorption coefficient (KF) values for the three soils were 10.67 (loam), 31.29 (clay) and 11.63 (sand). No notable photolysis of anilofos occurred on soil surface. Leaching tests, performed in manually packed soil glass-plate, indicated that anilofos moved very slowly on the three types of soil thin layer. Thus, the leaching behavior of anilofos coincided well with the results of the batch sorption and degradation experiments. The data generated from this study could be helpful for risk assessment studies of the pesticide in the environment.


Sign in / Sign up

Export Citation Format

Share Document