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Carlton L. Ho

Publications and source records attributed to Carlton L. Ho.

2 recordsLinked to original sources

Seismic slope-performance analysis: from hazard map to decision support system

In response to the growing recognition of engineers and decision-makers of the regional effects of earthquake-induced landslides, this paper presents a general approach to conducting seismic landslide zonation, based on the popular Newmark's sliding block analogy for modeling coherent landslides. Four existing models based on the sliding block analogy are compared. The comparison shows that the models forecast notably different levels of slope performance. Considering this discrepancy along with the limitations of static maps as a decision tool, a spatial decision support system (SDSS) for seismic landslide analysis is proposed, which will support investigations over multiple scales for any number of earthquake scenarios and input conditions. Most importantly, the SDSS will allow use of any seismic landslide analysis model and zonation approach. Developments associated with the SDSS will produce an object-oriented model for encapsulating spatial data, an object-oriented specification to allow construction of models using modular objects, and a direct-manipulation, dynamic user-interface that adapts to the particular seismic landslide model configuration.

Technical Council on Lifeline Earthquake Engineeri

Evaluation of viscoplastic slope movement based on triaxial tests

Viscoplastic soil parameters are used in a nonlinear viscoplastic constitutive model to predict time-dependent displacement of slow-moving landslides. The viscoplastic material parameters are determined by a novel method that uses a standard triaxial apparatus. This method employs data obtained from consolidated drained triaxial tests and consolidated drained stress-controlled strain-rate tests. The methodology was applied to undisturbed samples from the Minor Creek landslide in the Franciscan Terrane of northern California. Viscoplastic parameters determined from the laboratory tests were combined with boring log data to calculate the landslide’s vertical velocity profile. This profile provided a reasonable match to a measured velocity profile obtained from repetitive inclinometer surveys.

Book chapter