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Full-Text Articles in Geotechnical Engineering
Numerical Study Of Cone Penetration In Calcareous Sands: Investigating Cone Tip Resistance Correction Factors For Crushable Soils, Stephanie Michelle Hyder
Numerical Study Of Cone Penetration In Calcareous Sands: Investigating Cone Tip Resistance Correction Factors For Crushable Soils, Stephanie Michelle Hyder
Dissertations and Theses
The cone penetration test (CPT) is used to characterize the behavior and properties of soils, including the susceptibility to earthquake liquefaction triggering. The cone tip resistance relates to liquefaction susceptibility through relative density, where relative density is closely related to both cone tip resistance and liquefaction susceptibility. Currently, published methods of estimating liquefaction potential (i.e., cyclic resistance ratio) are based on silica sands and do not properly characterize calcareous sands. The measured cone tip resistance in calcareous sands is lower than in silica sands at the same relative density; this difference is generally attributed to the higher compressibility of calcareous …
Cyclic Behavior Of Transitional Fine-Grained Soils In Northern Willamette Valley, Frank Jarman
Cyclic Behavior Of Transitional Fine-Grained Soils In Northern Willamette Valley, Frank Jarman
Civil and Environmental Engineering Master's Project Reports
As discussed within studies from Idriss and Boulanger (2008) and Bray and Sancio (2006), the undrained cyclic shear behavior of low-plasticity fine-grained soils will transition between liquefaction (sand-like behavior) to cyclic softening (clay-like behavior) over a narrow range of plasticity index (PI). Despite not being sufficiently understood, the cyclic behavior of low plasticity silts has become an increasingly important field of study due to the significant impact it has on ground deformations and infrastructure failure in areas that are seismically active. Laboratory tests were performed on soils by third party consultants on a site located in the northern Willamette Valley, …
Liquefaction Triggering In Low-Plasticity Silts And Effects Of Liquefaction-Induced Lateral Spreading On A Reinforced-Concrete Pile, Jared A. Martinez
Liquefaction Triggering In Low-Plasticity Silts And Effects Of Liquefaction-Induced Lateral Spreading On A Reinforced-Concrete Pile, Jared A. Martinez
Civil and Environmental Engineering Master's Project Reports
Liquefaction triggering and post-liquefaction effects on lateral loading of deep foundations is an emerging area of study. This project presents: the results of cyclic direct simple shear (CDSS) testing on a low-plasticity alluvial silt collected in Portland, Oregon; and analysis of the combined effects of liquefaction-induced lateral spreading on a reinforced-concrete pile using data collected from a shake table test. The former research determines the liquefaction susceptibility and post-liquefaction characteristics of a local transitional soil using stress-controlled CDSS testing, the latter explores the complex lateral loading a reinforced-concrete pile undergoes during seismic loading with liquefaction-induced lateral spreading of the ground …
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 …
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 …
Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow
Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow
Graduate Theses and Dissertations
Slope failures in the United States alone cause millions of dollars in damage to infrastructure, threaten national monuments, create environmental hazards, and take an average of 25-50 lives a year. With the inevitable construction that occurs on slopes, it is imperative that the slopes be properly designed which requires a thorough understanding of slope grade, subsurface soil conditions, soil strength parameters, water table locations, and depth to bedrock across the entire site. The preferred method of data collection would be to use borings and other in-situ methods; however, sometimes due to cost constraints or site accessibility only a very limited …
A Unified Risk-Based Framework For Assessing Sustainability And Resiliency Of Civil Infrastructure, Thomas Adam Robbins
A Unified Risk-Based Framework For Assessing Sustainability And Resiliency Of Civil Infrastructure, Thomas Adam Robbins
Boise State University Theses and Dissertations
As of February 2019, the National Aeronautics and Space Administration (NASA) has reported since 1880 the average global temperature has increased 1°C, with the warmest year on record being 2016. As the years continue to pass, it is becoming more evident that climate change is occurring, which is known to be a catalyst for climatic weather events. Statistically speaking, these events are more prevalent, and catastrophic exemplified as hurricanes, earthquakes, flooding, and fires. In addition to the increase of potentially catastrophic events, society as a whole has become more conscientious in the use and preservation of natural resources, waste generation, …
Discussion: Effect Of Bentonite Slurry Pressure On Interface Friction Of Pipe Jacking, Ciaran Reilly, Trevor Orr
Discussion: Effect Of Bentonite Slurry Pressure On Interface Friction Of Pipe Jacking, Ciaran Reilly, Trevor Orr
Articles
Pipe jacking is a technique used to construct tunnels by pushing prefabricated pipes through the ground from an entrance shaft to an exit shaft. This technique is referred as microtunneling in U.S. terminology, therefore, in the rest of the text, pipejacking and microtunneling will be used as having the same meaning. Pipe jacking is a more economical alternative to segmental lined tunnels. However, the main limitation of pipe jacking is the jacking distance, which is directly dependent on the friction between the pipe and the soil. Therefore, reducing the friction between the pipe and soil is a critical issue in …
Stabilization Of Dredged Materials In Ohio: An Investigation Of Mechanical, Chemical And Biological Dewatering Techniques, Erika Howard
Stabilization Of Dredged Materials In Ohio: An Investigation Of Mechanical, Chemical And Biological Dewatering Techniques, Erika Howard
Williams Honors College, Honors Research Projects
Each year, materials are excavated from oceans and lakes in order to keep the waterways open so that ships can safely pass through. These excavated, or dredged, materials are then discarded, usually being returned to the body of water from which they were removed. Beginning in 2020, the Ohio Environmental Protection Agency (OEPA) will no longer allow this to occur. Therefore, the purpose of this project is to investigate beneficial uses for dredged materials in Lake Erie, and to address the best management practices for dewatering these materials, as set forth in the Lake Erie Protection and Restoration Plan created …
Geosynthetic Reinforcement For Unpaved Roads – Recent Experience, Ciaran Reilly, Keith Nell
Geosynthetic Reinforcement For Unpaved Roads – Recent Experience, Ciaran Reilly, Keith Nell
Conference papers
Modern geosynthetic materials, including geotextiles and geogrids, are often used to generate savings in materials and time on construction projects. Geosynthetics are used as reinforcement and separation membranes for unpaved roads that are supported by low strength or unsuitable subgrades. When geosynthetics are used, unsuitable subgrades can be left in place and reduced thicknesses of road base are required. This paper reviews the design methods currently used to build geosynthetic reinforced unpaved roads and documents the validation of these design approaches. A number of recent case histories of projects in the UK and Ireland are outlined, showing the use of …
Resistivity Profiles Of Perth Soil In Australia In Leak-Detection Test, Lopa M. Pandey, Sanjay K. Shukla, Daryoush Habibi
Resistivity Profiles Of Perth Soil In Australia In Leak-Detection Test, Lopa M. Pandey, Sanjay K. Shukla, Daryoush Habibi
Research outputs 2014 to 2021
The use of a suitable leak-detection system for the prevention and mitigation of pollution due to lining system failures is integral to the proper management of landfill facilities. This paper briefly summarises various methods of leak detection that are currently being practised. The details of a newly developed leak-detection technique are also presented. The tests were conducted to evaluate the performance of the new technique by use of controlled leakage. The resulting resistivity profiles for Perth soil in Australia were obtained at 10 min. This method is found to be effective in detecting and locating liner leakage issues within 30 …
Commercialization Of A Small, Lightweight, Low-Cost Seismic Borehole Receiver, Rachel Adams
Commercialization Of A Small, Lightweight, Low-Cost Seismic Borehole Receiver, Rachel Adams
Theses and Dissertations--Civil Engineering
Herein, conceptualization of a recently patented seismic borehole receiver and its components is developed for commercialization. The device is significantly cheaper, lighter, and smaller than existing technologies on the market. Additionally, it has the potential to achieve better seismic readings than its competitors via patented sensor-to-borehole coupling mechanism. It is the hope that the commercialization of this device will not only provide a more affordable alternative to engineers and geophysicists in the existing market, but the significant cost difference may open new seismic measurement opportunities in the developing world. Its compact size and light weight will increase mobility, allowing investigators …
Detecting Anomalous Inclusions In Soil Profiles: Encouraging The Use Of Geophysics To Solve Engineering Problems, Barbara Luke, Carlos Calderon-Macias
Detecting Anomalous Inclusions In Soil Profiles: Encouraging The Use Of Geophysics To Solve Engineering Problems, Barbara Luke, Carlos Calderon-Macias
Civil and Environmental Engineering and Construction Faculty Research
Geotechnical site investigations often do not take full advantage of geophysical methods. As examples, when delineating cemented strata and when detecting shallow cavities, investigations can be enhanced greatly for low additional cost by incorporating seismic surface-based measurements.