It is of significance to research failure mechanism of debris landslides that are widespread in the Three Gorges Reservoir Area. Based on the statistical analysis of the developmental law and failure mode of debris la...It is of significance to research failure mechanism of debris landslides that are widespread in the Three Gorges Reservoir Area. Based on the statistical analysis of the developmental law and failure mode of debris landslides in the Three Gorges Reservoir, the mode of progressive failure is found. The mechanical model for progressive failure of debris landslides with two slip bands is also established by applying slice method. According to the results of the downslide force between adjacent slices, if the downslide force of lower slice is larger than zero, the slice fails along the major sliding surface, otherwise it is stable. In result, the failure range is obtained. The stress function can be determined through dimensional analysis of failure slice. According to static boundary conditions of the slice, stress state of any point in the slice can be obtained. Then stress state of any point in the secondary slip band can also be established. The failure of the secondary slip band is judged on the basis of Mohr-Coulomb failure criterion. Therefore, a mechanical method is proposed to analyze the progressive failure of debris landslide with two slip bands.展开更多
The aim of this paper is to present works performed in HTC （Heat-Tech Center）, Research ＆ Development Centre of Veolia Group located in Warsaw regarding assessment of probability of failure in DHN （district heatin...The aim of this paper is to present works performed in HTC （Heat-Tech Center）, Research ＆ Development Centre of Veolia Group located in Warsaw regarding assessment of probability of failure in DHN （district heating network）. This work is a part of a project dedicated to develop a software which objective is to increase reliability of DHN. The research methods consisted of three approaches. First, using database of failures which happened in Warsaw DHN and repairing protocols from past 10 years, a statistics approach was applied to perform first analysis. The result was that pipelines with nominal diameter DN （nominal diameter） ≤ 150 had higher failure rate per km, than pipelines with DN 〉 150. The next step of research was to study influence of internal （corrosion caused by heat carrier, quality of materials） and external （stray currents） factor in order to assess its individual influence on failure rate of pipe and explain reasons of differences in failure rate. To end a FMEA （failure mode and＇effects analysis） will aim to identify the main failures modes appearing on DHN, to estimate the main causes of these failures and to propose the best solutions regarding the causes, the costs and the means available.展开更多
基金financially by National Natural Science Foundation Project "Shore Landslide and Risk Prediction of Secondary Surge Hazard in the Three Gorges Reservoir"(Grant No. 40872176)
文摘It is of significance to research failure mechanism of debris landslides that are widespread in the Three Gorges Reservoir Area. Based on the statistical analysis of the developmental law and failure mode of debris landslides in the Three Gorges Reservoir, the mode of progressive failure is found. The mechanical model for progressive failure of debris landslides with two slip bands is also established by applying slice method. According to the results of the downslide force between adjacent slices, if the downslide force of lower slice is larger than zero, the slice fails along the major sliding surface, otherwise it is stable. In result, the failure range is obtained. The stress function can be determined through dimensional analysis of failure slice. According to static boundary conditions of the slice, stress state of any point in the slice can be obtained. Then stress state of any point in the secondary slip band can also be established. The failure of the secondary slip band is judged on the basis of Mohr-Coulomb failure criterion. Therefore, a mechanical method is proposed to analyze the progressive failure of debris landslide with two slip bands.
文摘The aim of this paper is to present works performed in HTC （Heat-Tech Center）, Research ＆ Development Centre of Veolia Group located in Warsaw regarding assessment of probability of failure in DHN （district heating network）. This work is a part of a project dedicated to develop a software which objective is to increase reliability of DHN. The research methods consisted of three approaches. First, using database of failures which happened in Warsaw DHN and repairing protocols from past 10 years, a statistics approach was applied to perform first analysis. The result was that pipelines with nominal diameter DN （nominal diameter） ≤ 150 had higher failure rate per km, than pipelines with DN 〉 150. The next step of research was to study influence of internal （corrosion caused by heat carrier, quality of materials） and external （stray currents） factor in order to assess its individual influence on failure rate of pipe and explain reasons of differences in failure rate. To end a FMEA （failure mode and＇effects analysis） will aim to identify the main failures modes appearing on DHN, to estimate the main causes of these failures and to propose the best solutions regarding the causes, the costs and the means available.
