San Andreas Dam Geotechnical Investigations

Core Analysis and Model Building

A team of engineers was drilling holes through portions of the San Andreas Dam to obtain core samples for further investigation. 

The cores extracted are about 3-inches in diameter. They will be used to determine the content of the bedrock and fill used to create the layers of the earthen dam. Once the analysis is made and the layers determined, the engineers will create a 3-D model of the dam. This model will be used to see if previous earthquakes have weakened or changed the characteristics of the dam in ways that will need to be corrected. Also, the model can predict if the current conditions will need to be supplemented in order to prevent future problems due to earthquakes or other natural disaster.

While the sampling took just a few weeks of activity, the evaluation effort will extend for several years.

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