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Undrained Cyclic Loading Of Low Plasticity Silty Soils In The Pacific Northwest Using Laboratory And Field Cyclic Shear Testing, Angelica Melissa Preciado Reyes
Undrained Cyclic Loading Of Low Plasticity Silty Soils In The Pacific Northwest Using Laboratory And Field Cyclic Shear Testing, Angelica Melissa Preciado Reyes
Dissertations and Theses
The cyclic behavior of a fine-grained low plasticity silty soil (plasticity index of approximately 15) at a site in Portland, Oregon, is characterized using a field and laboratory cyclic shear test program. The field cyclic tests were performed using the NHERI@UTexas large mobile shakers T-Rex and Rattler. The laboratory tests were performed using resonant column torsional shear and cyclic direct simple shear devices. This testing program's results were used to evaluate the soil's potential to develop excess pore water pressure with cyclic shear strains ranging from 0.00001% to 3%. The laboratory cyclic test results are compared against field cyclic test …
Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young
Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young
Dissertations and Theses
Soils that are intermediate to sands and clays are a challenge for geotechnical engineers since most methods for interpreting soil properties or soil behaviors are based on sands or clays and do not address behaviors of intermediate soils. This is a particular challenge for engineers in the Portland-area where many of the major soil units are composed of intermediate soils. Analysis of intermediate soils is further challenged since many standard constitutive models are based on sandy or clay-like soils. However, the MIT-S1 constitutive model is capable of capturing intermediate soil behavior. A calibration of the MIT-S1 constitutive model for Portland-area …
Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman
Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman
Dissertations and Theses
The piezocone penetration test (CPTu) is a commonly used method of geotechnical site investigation. The CPTu is especially useful because it provides a nearly continuous data profile of in-situ soil behavior, which can be correlated to useful engineering parameters. However, limitations exist for interpretation of geotechnical properties from CPTu data and for numerical analysis of cone penetration problems. The research presented in this thesis examines interpretation of coefficient of consolidation from CPTu dissipation test data and implementation of an algorithm to advance numerical simulation of cone penetration problems. This thesis presents analysis of CPTu dissipation responses from field-measured and numerically …
Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt
Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt
Dissertations and Theses
Strong earthquake shaking is a natural hazard threat in the Pacific Northwest. Soil failure due to strong earthquake shaking -- known as cyclic soil failure or liquefaction -- is expected to cause large ground deformations and damage to roads, bridges, and other civil infrastructure. Cyclic soil strength (CRR) is often characterized with in-situ geotechnical tests including the cone penetration test (CPT). Relationships between CRR and in-situ test data are not well established for soils in the Pacific Northwest. Portland State University, in partnership with New Albion Geotechnical has compiled a database of cyclic lab tests for Pacific Northwest soils to …
Undrained Cyclic Shear Resistance Of Low Plastic Silts, Rawan Almoumen
Undrained Cyclic Shear Resistance Of Low Plastic Silts, Rawan Almoumen
Dissertations and Theses
A magnitude 9 Cascadia Subduction Zone earthquake is expected to trigger widespread liquefaction in loose material in Oregon. The geotechnical engineering studies have determined that the Willamette Silts may be susceptible to liquefaction or cyclic softening, as their plasticity indices ranges between non-plastic to low plasticity. While the majority of past studies have focused on liquefaction of sand and cyclic behavior of clays, there is not enough data on the cyclic response behavior of silty soils and the liquefaction susceptibility of these soils. A research focus in the geotechnical engineering program at Portland State University revolves around is performing cyclic …