In this paper, an attempt to analyse landslide hazard and vulnerability in the municipality of Pahuatlfin, Puebla, Mexico, is presented. In order to estimate landslide hazard, the susceptibility, magnitude （area-velo...In this paper, an attempt to analyse landslide hazard and vulnerability in the municipality of Pahuatlfin, Puebla, Mexico, is presented. In order to estimate landslide hazard, the susceptibility, magnitude （area-velocity ratio） and landslide frequency of the area of interest were produced based on information derived from a geomorphological landslide inventory; the latter was generated by using very high resolution satellite stereo pairs along with information derived from other sources （Google Earth, aerial photographs and historical information）. Estimations of landslide susceptibility were determined by combining four statistical techniques： （i） logistic regression, （ii） quadratic discriminant analysis, （iii） linear discriminant analysis, and （iv） neuronal networks. A Digital Elevation Model （DEM） of lo m spatial resolution was used to extract the slope angle, aspect, curvature, elevation and relief. These factors, in addition to land cover, lithology anddistance to faults, were used as explanatory variables for the susceptibility models. Additionally, a Poisson model was used to estimate landslide temporal frequency, at the same time as landslide magnitude was obtained by using the relationship between landslide area and the velocity of movements. Then, due to the complexity of evaluating it, vulnerability of population was analysed by applying the Spatial Approach to Vulnerability Assessment （SAVE） model which considered levels of exposure, sensitivity and lack of resilience. Results were expressed on maps on which different spatial patterns of levels of landslide hazard and vulnerability were found for the inhabited areas. It is noteworthy that the lack of optimal methodologies to estimate and quantify vulnerability is more notorious than that of hazard assessments. Consequently, levels of uncertainty linked to landslide risk assessment remain a challenge to be addressed.展开更多
In this paper, the behavior of barrel-vaulted structures undergoing rocking of the abutments and the effectiveness of a few retrofit solutions are discussed. The comprehension of the structural performance of vault-ab...In this paper, the behavior of barrel-vaulted structures undergoing rocking of the abutments and the effectiveness of a few retrofit solutions are discussed. The comprehension of the structural performance of vault-abutment systems is fundamental for their seismic vulnerability assessment, and for the design of efficient strengthening techniques. In the paper, traditional techniques such as extrados thin concrete slab or masonry spandrel walls as well as an innovative solution with an extrados thin improved lime mortar slab reinforced by means of glass fiber mesh are considered. The different strengthening solutions are studied and compared on the basis of the results of non linear numerical analyses and by reference to a simplified analytical approach. Numerical and analytical models are validated through comparison with the results of a recent experimental study focusing on the behavior of vaulted masonry structures subjected to rocking of the abutments. The validated models can be used by engineers for the seismic vulnerability assessment of masonry vaulted structures as well as for the proportioning of possible extrados strengthening solutions, and will be used in the future to explore different structural system configurations.展开更多
基金CONACyT for financial support for the research project 156242for providing a post-graduate scholarship
文摘In this paper, an attempt to analyse landslide hazard and vulnerability in the municipality of Pahuatlfin, Puebla, Mexico, is presented. In order to estimate landslide hazard, the susceptibility, magnitude （area-velocity ratio） and landslide frequency of the area of interest were produced based on information derived from a geomorphological landslide inventory; the latter was generated by using very high resolution satellite stereo pairs along with information derived from other sources （Google Earth, aerial photographs and historical information）. Estimations of landslide susceptibility were determined by combining four statistical techniques： （i） logistic regression, （ii） quadratic discriminant analysis, （iii） linear discriminant analysis, and （iv） neuronal networks. A Digital Elevation Model （DEM） of lo m spatial resolution was used to extract the slope angle, aspect, curvature, elevation and relief. These factors, in addition to land cover, lithology anddistance to faults, were used as explanatory variables for the susceptibility models. Additionally, a Poisson model was used to estimate landslide temporal frequency, at the same time as landslide magnitude was obtained by using the relationship between landslide area and the velocity of movements. Then, due to the complexity of evaluating it, vulnerability of population was analysed by applying the Spatial Approach to Vulnerability Assessment （SAVE） model which considered levels of exposure, sensitivity and lack of resilience. Results were expressed on maps on which different spatial patterns of levels of landslide hazard and vulnerability were found for the inhabited areas. It is noteworthy that the lack of optimal methodologies to estimate and quantify vulnerability is more notorious than that of hazard assessments. Consequently, levels of uncertainty linked to landslide risk assessment remain a challenge to be addressed.
文摘In this paper, the behavior of barrel-vaulted structures undergoing rocking of the abutments and the effectiveness of a few retrofit solutions are discussed. The comprehension of the structural performance of vault-abutment systems is fundamental for their seismic vulnerability assessment, and for the design of efficient strengthening techniques. In the paper, traditional techniques such as extrados thin concrete slab or masonry spandrel walls as well as an innovative solution with an extrados thin improved lime mortar slab reinforced by means of glass fiber mesh are considered. The different strengthening solutions are studied and compared on the basis of the results of non linear numerical analyses and by reference to a simplified analytical approach. Numerical and analytical models are validated through comparison with the results of a recent experimental study focusing on the behavior of vaulted masonry structures subjected to rocking of the abutments. The validated models can be used by engineers for the seismic vulnerability assessment of masonry vaulted structures as well as for the proportioning of possible extrados strengthening solutions, and will be used in the future to explore different structural system configurations.
