Vertical spatial correlation length based on standard penetration tests

Oguz, Emir Ahmet; Huvaj, Nejan; Griffiths, D. V.

doi:10.1080/1064119x.2018.1443180

Cited by 26 publications

(11 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the current study, offshore/nearshore CPT measurements and soil mechanics laboratory test results are evaluated statistically. For the classification of the soil at each depth, and decision on the layer boundaries of the soil profile, an automatic evaluation of the CPT data is performed by a MATLAB code developed in this study (Oguz 2017).…”

Section: Methods Of Analysesmentioning

confidence: 99%

“…The moisture content, Atterberg limits, specific gravity, unit weight, grain size distribution, pocket penetrometer, torvane, and unconsolidated undrained (UU) triaxial tests were available on disturbed and undisturbed soil samples (Oguz 2017). For the broad groups of "clays" and "sands" used in this study, undrained shear strength and relative density are evaluated by using empirical equations.…”

Section: Soil Propertiesmentioning

confidence: 99%

“…Secondly, CPT data is analyzed to evaluate the vertical SCL of CPT cone tip resistance, sleeve friction and friction ratio using four different autocovariance functions proposed by Vanmarcke (1977). For these purposes, a MATLAB code is developed to take the CPT data, identify individual soil layers, carry out statistical evaluation of the properties of soils and report the vertical SCL of each layer using four different autocovariance functions (Oguz 2017). The results of the present study add to the limited database of offshore SCLs based on real data (Table 1) and could be useful for future studies on reliability assessment of offshore foundations.…”

Section: Introductionmentioning

confidence: 98%

“…In this study, 65 CPT data (Oguz 2017) reaching to 200 m depths in seabed soils, in up to 64-m water depths, in the northwestern part of Turkey is processed, and properties of sea bottom soils are presented. The data is analyzed, firstly, to determine the types and characteristics of the soils in the seabed, whether they are uniform or multi-layered, whether the consistency of clays is soft or stiff, and whether the sandy soils are in loose or dense state, etc.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Spatial probabilistic evaluation of offshore/nearshore sea bottom soils based on cone penetration tests

Oguz

Huvaj

2019

Bull Eng Geol Environ

Self Cite

View full text Add to dashboard Cite

The inherent variability of soil has a crucial role in reliability-based design, especially for offshore foundations where the variability and uncertainty are more critical due to high costs as compared to the onshore counterparts. In this study, spatial probabilistic evaluation of the characteristics of offshore/nearshore sea bottom soils is performed based on data of 65 cone penetration tests (CPTs), reaching to 200-m depths in seabed soils, in up to 64 m of water. The types and typical characteristics of sea bottom soils are reported, together with statistical evaluation. A key parameter for random field theory, the spatial correlation length, based on CPT data is obtained for different soil types, using four different autocovariance functions (exponential, squared exponential, cosine exponential and second-order autoregressive). For these purposes, a MATLAB code is developed to take the CPT data, identify individual soil layers, carry out statistical evaluation of the properties of soils and report the vertical spatial correlation length of each layer using four different autocovariance functions. The undrained shear strength of clays in nearshore and offshore soils increases with depth, at rates of 1 to 3 kPa/m. Sands nearshore and offshore have similar relative density that is generally less than 50% (i.e. in loose to medium-dense state). The vertical spatial correlation length based on CPT of all soils is in the range of 0.11 m to 0.27 m, for all four different autocovariance functions, for all CPT cone tip resistances, sleeve friction and friction ratio, and for all shallow-and deep-water soils. The vertical spatial correlation length of nearshore soils is slightly larger than offshore soils. The results add to the scarce data on the spatial correlation length of offshore soils and can be useful for future studies on reliability and risk assessment of nearshore/offshore foundations.

show abstract

Section: Methods Of Analysesmentioning

confidence: 99%

Section: Soil Propertiesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Spatial probabilistic evaluation of offshore/nearshore sea bottom soils based on cone penetration tests

Oguz

Huvaj

2019

Bull Eng Geol Environ

Self Cite

View full text Add to dashboard Cite

show abstract

“…Different soil properties have been studied spatially based on the CPT, such as undrained cohesion [2] and liquefaction potential of soil [3 -5]. Field tests have also been successfully used for analyzing soil variabilities including the vane shear test [6], Standard Penetration Test (SPT) [7] and CPT [8,9]. Researchers have dealt with different soils such as weathered soil [10] and soft soil [9].…”

Section: Introductionmentioning

confidence: 99%

Spatial Correlation of Cone Tip Resistance for Soil in Nasiriyah

Shakir¹

2018

TOCIEJ

View full text Add to dashboard Cite

Background:Quantification of soil property spatial variations is an important step in any reliability-based design. Little stochastic parameter information about the soil in Nasiriyah, which is in southern Iraq, is available.Methods:In this paper, the Scale Of Fluctuation (SOF) for the site soil is examined, which is suggested for construction of the refinery fuel station project as no random parametric quantity has been studied in this region. A Cone Penetration Test (CPT) was performed as part of the site investigation to a depth of 20 m in the vertical direction, and 24 CPTs were analyzed within the site. The spatial correlation was computed using four methods, including Single Exponent (SNE), Square Exponent (SQE), Cosine Exponent (CSE) and Second-Order Markov (SOM). Identification of the soil type depended on the most recent classification chart, which is based on CPT results. The spatial correlation was evaluated for the vertical direction considering the cone tip resistance (qc) component. Three trend functions were applied to all CPT soundings, including linear, quadratic and cubic polynomials, which were utilized to transform the non-stationary data to stationary data. Three modes of soil were employed, including the eight-meter soil layer, a twelve-meter soil layer and the entire twenty meters of soil, which includes both layers.Results and Discussion:The mean values of SOF were 0.54 m, 0.53 m, and 1.73 m for soil layers 8 m, 12 m, and 20 m, respectively. The high value of the last mean is attributed to the 20 m of stratification in the ground. This study also indicates that the SOF decreases as the polynomial degree increases, which is due to enhanced fitting. The coefficient of variation (COV) for the SOF shows little variability for most of the studied soil cases.

show abstract