The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform

Steven F. Bartlett - One of the best experts on this subject based on the ideXlab platform.

  • Construction and Long-Term Settlement Performance Monitoring of MSE Walls Constructed With and Without Soil Improvement
    2015
    Co-Authors: Steven F. Bartlett, Clifton B Farnsworth, Bret N. Lingwall
    Abstract:

    The I-15 Reconstruction Project, completed in 2001 just before the 2002 Winter Olympic Games in Salt Lake City, Utah, incorporated several innovative embankment and foundation treatments as part of a fast-paced, 4-year, $1.5 billion design-build project. In many cases rapid construction techniques were required to facilitate construction over relatively soft, compressible, clayey foundation soils present over much of the northern I-15 alignment. Prefabricated vertical (PV) drains were used in conjunction with preloading for a large part of the alignment to accelerate Primary Consolidation Settlement and reduce secondary Consolidation Settlement, respectively, under relatively large, one- and two-staged mechanically stabilized earth (MSE) walls. This paper compares and contrasts the Primary and secondary Consolidation performance of two MSE walls. The first site is located at 200 South Street and is a two-stage MSE wall constructed without soil improvement atop compressible lacustrine deposits. The second site is at 300 West Street is a one-stage MSE wall constructed atop lime cement columns (LCC) treated soils. Extensive geotechnical and survey instrumentation were used to measure the Settlement underneath and adjacent to these wall systems. These monitoring data show that both wall systems generally met project performance goals; however the LCC treated MSE wall have superior performance in terms of reducing both the magnitude and distribution of the ground Settlement underneath and adjacent to the wall face. The monitoring data also give valuable insight into the rate of Settlement at these two locales and the influence of surcharging and soil improvement on reducing long-term (i.e., creep) Settlement.

  • estimation of time rate of Settlement for multilayered clays undergoing radial drainage
    Transportation Research Record, 2013
    Co-Authors: Clifton B Farnsworth, Steven F. Bartlett, Evert C Lawton
    Abstract:

    This paper demonstrates how the finite difference technique can be used to estimate the time rate of Settlement for soft, compressible clayey soils treated with prefabricated vertical drains at sites where Primary Consolidation Settlement is occurring in a multilayered system at varying rates. Semiempirical methods based on surface Settlement monitoring have typically been used to estimate the progression of Primary Consolidation Settlement. However, interpretation of such methods can be problematic for multilayered soil profiles. For such sites, it is crucial to obtain a reasonable characterization of the foundation soils' horizontal drainage properties and include these estimates in the time rate of Settlement projections. Field monitoring of subsurface instrumentation is extremely valuable in providing additional information about the Consolidation behavior of different layers. When subsurface field measurements are coupled with the proposed numerical method, far more reliable projections are obtained....

  • Estimation of Time Rate of Settlement for Multilayered Clays Undergoing Radial Drainage
    Transportation Research Record: Journal of the Transportation Research Board, 2013
    Co-Authors: Clifton B Farnsworth, Steven F. Bartlett, Evert C Lawton
    Abstract:

    This paper demonstrates how the finite difference technique can be used to estimate the time rate of Settlement for soft, compressible clayey soils treated with prefabricated vertical drains at sites where Primary Consolidation Settlement is occurring in a multilayered system at varying rates. Semiempirical methods based on surface Settlement monitoring have typically been used to estimate the progression of Primary Consolidation Settlement. However, interpretation of such methods can be problematic for multilayered soil profiles. For such sites, it is crucial to obtain a reasonable characterization of the foundation soils’ horizontal drainage properties and include these estimates in the time rate of Settlement projections. Field monitoring of subsurface instrumentation is extremely valuable in providing additional information about the Consolidation behavior of different layers. When subsurface field measurements are coupled with the proposed numerical method, far more reliable projections are obtained. This paper focuses on how to integrate field and laboratory data with projections of time rate of Settlement obtained from semiempirical and finite difference methods to predict more accurately the time rate of Consolidation behavior of multilayered foundation soils.

  • rapid construction and Settlement behavior of embankment systems on soft foundation soils
    Journal of Geotechnical and Geoenvironmental Engineering, 2008
    Co-Authors: C B Farnsworth, Dawit Negussey, Steven F. Bartlett, Armin W Stuedlein
    Abstract:

    The I-15 Reconstruction Project in Salt Lake City, Utah required rapid embankment construction in an urban environment atop soft lacustrine soils. These soils are compressible, have low shear strength, and require significant time to complete Primary Consolidation Settlement. Because of this, innovative embankment systems and foundation treatments were employed to complete construction within the approved budget and demanding schedule constraints. This paper evaluates and compares the construction time, cost, and performance of three embankment/foundation systems used on this project: (1) one-stage mechanically stabilized earth (MSE) wall supported by lime cement columns; (2) expanded polystyrene (geofoam) embankment with tilt-up panel fascia walls; and (3) two-stage MSE wall with prefabricated vertical drain installation and surcharging. Of the technologies evaluated, the geofoam embankment had the best performance based on Settlement and rapid construction time considerations, but is more costly to construct than a two-stage MSE wall with PV drain foundation treatment. The one-stage MSE wall with lime cement treated soil was the most costly, and did not perform as well as expected; thus, it had only limited use on the project.

  • Numerical Modeling of Settlement Behavior of Treated and Untreated Foundation Soils Underlying MSE Walls for the I-15 Reconstruction Project, Salt Lake City, Utah
    2006
    Co-Authors: Michelle D Cline, Steven F. Bartlett
    Abstract:

    As urban environments become more populated, it is becoming more common to construct larger highway embankments in close proximity to existing facilities. For such embankments constructed on soft, compressible soils, the design engineers must consider the Settlement impacts to adjacent structures. During the recent I-15 Reconstruction Project in Salt Lake City, Utah, several large mechanically stabilized earth (MSE) walls were constructed over compressible soils. In order to increase the stiffness and strength of very soft foundation materials in some locations along the corridor, these soils were treated with prefabricated vertical (PV) drains, and in one location, foundation soils were treated with lime cement columns (LCCs). Various types of instrumentation were installed and monitored during and following construction to collect Settlement data. These performance data have been used along with a suite of numerical modeling analyses as part of this research to evaluate the effectiveness of numerical modeling as a tool to predict Primary Consolidation Settlement. Two sites along the I-15 Reconstruction Project alignment were evaluated. Performance data collected from the 200 South Site, treated with PV drains, were used to back-calculate soil parameters for numerical analysis of the I-80 Site, treated with LCCs. Linear elastic (LE) and hyperbolic non-linear elastic (HNLE) models were considered. As expected, the HNLE model is a better predictor of Primary Consolidation Settlement than the LE model; however, this approach may only be warranted for critical facilities because a significant amount of effort is required to produce reasonably accurate results. In addition to conducting numerical analyses, this study established guidelines for Settlement versus embankment height based on the performance data. As a conservative approximation, embankments should be constructed a distance of at least 1.5 times the maximum embankment height to limit Settlements to 25 mm (1 in.) or less.

Andrew Palmer - One of the best experts on this subject based on the ideXlab platform.

  • INSTRUMENTATION AND CONSTRUCTION PERFORMANCE MONITORING FOR I-15 RECONSTRUCTION PROJECT IN SALT LAKE CITY, UTAH
    Transportation Research Record, 2001
    Co-Authors: Steven F. Bartlett, Greg Monley, Andrew Soderborg, Andrew Palmer
    Abstract:

    The I-15 reconstruction project in Salt Lake City, Utah, involves the widening and rebuilding of 27 km of urban Interstate on alluvial and lacustrine deposits. In some locales, these soils have low shear strength and require up to 2 to 3 years to complete Primary Consolidation Settlement. The aggressive 4-year construction schedule required much of the embankment and foundation work to be completed in the first 12 to 18 months, including the time required to complete Primary Settlement. To meet these rigorous schedule constraints, the geotechnical construction made extensive use of prefabricated vertical drains, ground modification, staged embankment construction, lightweight fill, mechanically stabilized earth walls, and pile foundations. Also, because of rigid time constraints, initial foundation treatments and embankment construction proceeded as parallel activities with the geotechnical design. Instrumentation and construction performance monitoring played a vital role in affirming initial design assumptions and developing a better understanding of strength, deformation, and Consolidation characteristics of the foundation soils. Discussed are the instrumentation program and how performance monitoring was implemented to control construction processes and improve the geotechnical design.

Evert C Lawton - One of the best experts on this subject based on the ideXlab platform.

  • estimation of time rate of Settlement for multilayered clays undergoing radial drainage
    Transportation Research Record, 2013
    Co-Authors: Clifton B Farnsworth, Steven F. Bartlett, Evert C Lawton
    Abstract:

    This paper demonstrates how the finite difference technique can be used to estimate the time rate of Settlement for soft, compressible clayey soils treated with prefabricated vertical drains at sites where Primary Consolidation Settlement is occurring in a multilayered system at varying rates. Semiempirical methods based on surface Settlement monitoring have typically been used to estimate the progression of Primary Consolidation Settlement. However, interpretation of such methods can be problematic for multilayered soil profiles. For such sites, it is crucial to obtain a reasonable characterization of the foundation soils' horizontal drainage properties and include these estimates in the time rate of Settlement projections. Field monitoring of subsurface instrumentation is extremely valuable in providing additional information about the Consolidation behavior of different layers. When subsurface field measurements are coupled with the proposed numerical method, far more reliable projections are obtained....

  • Estimation of Time Rate of Settlement for Multilayered Clays Undergoing Radial Drainage
    Transportation Research Record: Journal of the Transportation Research Board, 2013
    Co-Authors: Clifton B Farnsworth, Steven F. Bartlett, Evert C Lawton
    Abstract:

    This paper demonstrates how the finite difference technique can be used to estimate the time rate of Settlement for soft, compressible clayey soils treated with prefabricated vertical drains at sites where Primary Consolidation Settlement is occurring in a multilayered system at varying rates. Semiempirical methods based on surface Settlement monitoring have typically been used to estimate the progression of Primary Consolidation Settlement. However, interpretation of such methods can be problematic for multilayered soil profiles. For such sites, it is crucial to obtain a reasonable characterization of the foundation soils’ horizontal drainage properties and include these estimates in the time rate of Settlement projections. Field monitoring of subsurface instrumentation is extremely valuable in providing additional information about the Consolidation behavior of different layers. When subsurface field measurements are coupled with the proposed numerical method, far more reliable projections are obtained. This paper focuses on how to integrate field and laboratory data with projections of time rate of Settlement obtained from semiempirical and finite difference methods to predict more accurately the time rate of Consolidation behavior of multilayered foundation soils.

Nie Wen - One of the best experts on this subject based on the ideXlab platform.

  • Design chart for the modified hyperbolic method
    Soils and Foundations, 2018
    Co-Authors: Wei Guo, Jian Chu, Nie Wen
    Abstract:

    Abstract The modified hyperbolic method is used in practice to predict the ultimate Primary Consolidation Settlement of compressible ground. This paper presents a new relationship between the average degree of Consolidation for combined vertical and horizontal Consolidation Uvh and the non-dimensional vertical time factor Tv, with a new parameter, νhv, introduced. νhv is defined as the ratio of the time factor in the horizontal direction to that in the vertical direction. This relationship is then adopted to calculate the slope of the linear segment of the theoretical hyperbolic plot (Tv/Uvh vs Tv), λ, which is a key factor in the modified hyperbolic observational method presented by Tan (1995). A design chart for λ as a function of νhv is proposed. Using this design chart, the determination for λ can be simplified from a procedure involving three parameters to only one, νhv. A new procedure for the use of the modified hyperbolic method is proposed. The new procedure is verified using a well-documented case history.

  • Design chart for the modified hyperbolic method
    'Elsevier BV', 2018
    Co-Authors: Guo Wei, Chu Jian, Nie Wen
    Abstract:

    The modified hyperbolic method is used in practice to predict the ultimate Primary Consolidation Settlement of compressible ground. This paper presents a new relationship between the average degree of Consolidation for combined vertical and horizontal Consolidation Uvh and the non-dimensional vertical time factor Tv, with a new parameter, νhv, introduced. νhv is defined as the ratio of the time factor in the horizontal direction to that in the vertical direction. This relationship is then adopted to calculate the slope of the linear segment of the theoretical hyperbolic plot (Tv/Uvh vs Tv), λ which is a key factor in the modified hyperbolic observational method presented by Tan (1995). A design chart for λ as a function of νhv is proposed. Using this design chart, the determination for λ can be simplified from a procedure involving three parameters to only one, νhv. A new procedure for the use of the modified hyperbolic method is proposed. The new procedure is verified using a well-documented case history.Published versio

Clifton B Farnsworth - One of the best experts on this subject based on the ideXlab platform.

  • Construction and Long-Term Settlement Performance Monitoring of MSE Walls Constructed With and Without Soil Improvement
    2015
    Co-Authors: Steven F. Bartlett, Clifton B Farnsworth, Bret N. Lingwall
    Abstract:

    The I-15 Reconstruction Project, completed in 2001 just before the 2002 Winter Olympic Games in Salt Lake City, Utah, incorporated several innovative embankment and foundation treatments as part of a fast-paced, 4-year, $1.5 billion design-build project. In many cases rapid construction techniques were required to facilitate construction over relatively soft, compressible, clayey foundation soils present over much of the northern I-15 alignment. Prefabricated vertical (PV) drains were used in conjunction with preloading for a large part of the alignment to accelerate Primary Consolidation Settlement and reduce secondary Consolidation Settlement, respectively, under relatively large, one- and two-staged mechanically stabilized earth (MSE) walls. This paper compares and contrasts the Primary and secondary Consolidation performance of two MSE walls. The first site is located at 200 South Street and is a two-stage MSE wall constructed without soil improvement atop compressible lacustrine deposits. The second site is at 300 West Street is a one-stage MSE wall constructed atop lime cement columns (LCC) treated soils. Extensive geotechnical and survey instrumentation were used to measure the Settlement underneath and adjacent to these wall systems. These monitoring data show that both wall systems generally met project performance goals; however the LCC treated MSE wall have superior performance in terms of reducing both the magnitude and distribution of the ground Settlement underneath and adjacent to the wall face. The monitoring data also give valuable insight into the rate of Settlement at these two locales and the influence of surcharging and soil improvement on reducing long-term (i.e., creep) Settlement.

  • estimation of time rate of Settlement for multilayered clays undergoing radial drainage
    Transportation Research Record, 2013
    Co-Authors: Clifton B Farnsworth, Steven F. Bartlett, Evert C Lawton
    Abstract:

    This paper demonstrates how the finite difference technique can be used to estimate the time rate of Settlement for soft, compressible clayey soils treated with prefabricated vertical drains at sites where Primary Consolidation Settlement is occurring in a multilayered system at varying rates. Semiempirical methods based on surface Settlement monitoring have typically been used to estimate the progression of Primary Consolidation Settlement. However, interpretation of such methods can be problematic for multilayered soil profiles. For such sites, it is crucial to obtain a reasonable characterization of the foundation soils' horizontal drainage properties and include these estimates in the time rate of Settlement projections. Field monitoring of subsurface instrumentation is extremely valuable in providing additional information about the Consolidation behavior of different layers. When subsurface field measurements are coupled with the proposed numerical method, far more reliable projections are obtained....

  • Estimation of Time Rate of Settlement for Multilayered Clays Undergoing Radial Drainage
    Transportation Research Record: Journal of the Transportation Research Board, 2013
    Co-Authors: Clifton B Farnsworth, Steven F. Bartlett, Evert C Lawton
    Abstract:

    This paper demonstrates how the finite difference technique can be used to estimate the time rate of Settlement for soft, compressible clayey soils treated with prefabricated vertical drains at sites where Primary Consolidation Settlement is occurring in a multilayered system at varying rates. Semiempirical methods based on surface Settlement monitoring have typically been used to estimate the progression of Primary Consolidation Settlement. However, interpretation of such methods can be problematic for multilayered soil profiles. For such sites, it is crucial to obtain a reasonable characterization of the foundation soils’ horizontal drainage properties and include these estimates in the time rate of Settlement projections. Field monitoring of subsurface instrumentation is extremely valuable in providing additional information about the Consolidation behavior of different layers. When subsurface field measurements are coupled with the proposed numerical method, far more reliable projections are obtained. This paper focuses on how to integrate field and laboratory data with projections of time rate of Settlement obtained from semiempirical and finite difference methods to predict more accurately the time rate of Consolidation behavior of multilayered foundation soils.