1. The Use of Full Flow Penetrometers in an Intermediate Soil; Silt By: Alan Abad & Mark Jones

2. The Motivation for this Quest to Discovery This study focused in the use of three types of in situ penetrometers in order to identify the behavior of intermediate soils and their susceptibility to liquefaction This study focused in the use of three types of in situ penetrometers in order to identify the behavior of intermediate soils and their susceptibility to liquefaction Testing with these tools was done at multiple penetration rates and with cyclic penetration Testing with these tools was done at multiple penetration rates and with cyclic penetration Prior to this study little was known about the implementation of full flow penetrometers in situ in intermediate soils Prior to this study little was known about the implementation of full flow penetrometers in situ in intermediate soils

3. Our Path to Discovery The scope of the project required a background in both civil and mechanical engineering The scope of the project required a background in both civil and mechanical engineering In a combined effort to get the desired results, MJ focused on the geotechnical aspects while AA focused on the mechanical tools In a combined effort to get the desired results, MJ focused on the geotechnical aspects while AA focused on the mechanical tools

4. What is Silt? It is a type of soil produced by the mechanical weathering of rock It is a type of soil produced by the mechanical weathering of rock It could happen due to grinding of glaciers, sandblasting by the wind and water erosion on the beds of rivers and streams It could happen due to grinding of glaciers, sandblasting by the wind and water erosion on the beds of rivers and streams It displays clay-like and sand-like properties It displays clay-like and sand-like properties It feels like flour and it’s hard to work with It feels like flour and it’s hard to work with LARGEST Gravel Sand Silt Clay Smallest

5. Silt Sample Preparation MJ’s Goal The best sample preparation method is one that, when completed, best resembles an actual undisturbed sample from the field The best sample preparation method is one that, when completed, best resembles an actual undisturbed sample from the field Two samples of uniformly deposited commercially available silt where prepared: Two samples of uniformly deposited commercially available silt where prepared: One in a dense state by air pluviation, and the other in a looser state by pluviation through water

6. Silt and the Pluviator The Pluviator The Mold The Silt The wet pluviated sample

7. The Need for Tools AA’s Goal Penetrometers are devices used to measure the firmness or resistance to penetration of soil Penetrometers are devices used to measure the firmness or resistance to penetration of soil T-Bar, Ball and Cone penetrometers are tools used during in situ investigations of soft clays offshore T-Bar, Ball and Cone penetrometers are tools used during in situ investigations of soft clays offshore With the use of these tools, we attempted to characterize the uniformity, undrained and remolded strength and liquefaction resistance of silts With the use of these tools, we attempted to characterize the uniformity, undrained and remolded strength and liquefaction resistance of silts

8. The Penetrometers Journey With the use of Solidworks the first sketches of the tools were drawn to scale to fit the hydraulic actuator with which they will be used With the use of Solidworks the first sketches of the tools were drawn to scale to fit the hydraulic actuator with which they will be used By using a lathe and welder the different types of penetrometers and with their different ratios were brought to life By using a lathe and welder the different types of penetrometers and with their different ratios were brought to life

9. The Tools that made the Tools The Solidworks Design The Final Outcome The Lathe- what made them Hydraulic Actuator- what they were designed for

10. How it all came together Once the specimen preparation method had been developed, and the penetrometers fabricated and calibrated, we were able to test the silt Once the specimen preparation method had been developed, and the penetrometers fabricated and calibrated, we were able to test the silt Important information that we needed to perform quality reduced scale testing: Important information that we needed to perform quality reduced scale testing:  Area Ratios; Projected area/ push rod area. We used 2/1, 5/1, 10/1 and 15/1 ratios for our probes  Rates; Velocity/diameter of probe = rate. In our tests we used 0.005, 0.05, 0.5 and 5.0 rates  Test Profile; initial penetration, cycling, final penetration and extraction  Cycling; 10 up and down cycles within a specified height

11. The Testing Process For the actual testing there were many other variables that needed to be fixed such as: For the actual testing there were many other variables that needed to be fixed such as:  Learning how to properly use and manipulate Labview to control the testing systems  Learning how to calibrate amplifiers and loadcells for accurate data measuring  Learning how to operate the hydraulic pumps with caution Network failures, limited availability of some of the equipment and undesirable results were some of the problems we had to overcome along the way Network failures, limited availability of some of the equipment and undesirable results were some of the problems we had to overcome along the way

12. Our Discovery After all the testing was concluded and all the data carefully analyzed we were able to determine that penetration resistance tends to increase with increased penetration rate After all the testing was concluded and all the data carefully analyzed we were able to determine that penetration resistance tends to increase with increased penetration rate  Such behavior was expected based on the characteristics of both sands and clays Cyclic penetration of the penetrometers resulted in rapid strength degradation of the silt, most likely due to the quick increase in pore water pressure resulting from penetration Cyclic penetration of the penetrometers resulted in rapid strength degradation of the silt, most likely due to the quick increase in pore water pressure resulting from penetration  Such strength degradation is similar to that of sensitive clays There is minimal or almost no resistance during extraction There is minimal or almost no resistance during extraction  Very different from clay

13. Our Results Graph of test conducted with a 10/1 T- bar at a ratio of 5.0 Graph of test conducted with a 10/1 T- bar at a ratio of 0.05 ▪ For visual purposes different scales were used on both graphs. The test with the 0.05 ratio is almost 100X smaller than that of the test with the 5.0 ratio.

14. How it applies to Earthquake Engineering The results of this study are important for the evaluation of site response to earthquake motions through: The results of this study are important for the evaluation of site response to earthquake motions through:  Characterization of intermediate soils  Evaluation of their behavior The rapid loss of strength resulting from cyclic loading is of particular importance when evaluating the potential of ground movement resulting from an earthquake The rapid loss of strength resulting from cyclic loading is of particular importance when evaluating the potential of ground movement resulting from an earthquake

15. Future Plans We hope to see our findings being of some help and use for in situ studies We hope to see our findings being of some help and use for in situ studies And some day down the road….. And some day down the road…..

16. Acknowledgements Special thanks to:  Jason DeJong  Nick Yafrate  Chad Justice And all the others who contributed into making this quest to discovery possible

17. Any Questions? Thank you.