Ronald Andrus

In this paper, a new approach is presented for developing a liquefaction limit state function, wh... more In this paper, a new approach is presented for developing a liquefaction limit state function, which defines a boundary that separates liquefaction from no-liquefaction occurrence. The new approach is developed using a database consisting of 243 field liquefaction performance cases at sites where standard penetration tests (SPT) had been conducted. This database is first used to train and test an artificial neural network for predicting the occurrence of liquefaction or no liquefaction. The successfully trained neural network is then used to establish a liquefaction limit state function. Based on the developed limit state function, mapping functions that relate calculated factors of safety to probability of liquefaction are established. The established mapping functions form a basis for the development of a risk-based chart for liquefaction potential evaluation.Key words: probability, risk-based design, liquefaction potential, SPT, artificial neural network.

Liquefaction Resistance of Soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils

Journal of Geotechnical and Geoenvironmental Engineering, 2001

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Predicting Shear-Wave Velocity from Cone Penetration Resistance

Empirical equations for predicting the small-strain shear-wave velocity, VS, of soils of differen... more Empirical equations for predicting the small-strain shear-wave velocity, VS, of soils of different geologic age from cone penetration resistance are presented in this paper. The equations are determined using data from 229 soil layers in California, South Carolina and Japan. Of the 229 soil layers, 72 are of Holocene age, 113 of Pleistocene age, and 44 of Tertiary age. Variables considered in the development of the equations include: cone tip and sleeve resistances, depth, overburden pressure, soil behavior type index, and geologic age. It is found that VS is on average 22-26 % greater in the Pleistocene soils and 129-137 % greater in the Tertiary-age Cooper Marl than in the Holocene soils with the same tip resistance. These results clearly indicate the need to consider geologic age, as well as cementation, when predicting VS from cone measurements. The new equations are particularly useful where it is not economically feasible to measure VS at all desired locations.

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Peak Shear Strength and Dilatancy of a Pleistocene Age Sand

Journal of Geotechnical and Geoenvironmental Engineering

At-Rest Lateral Stress Coefficient in Sands from Common Field Methods

Journal of Geotechnical and Geoenvironmental Engineering

State of the art in the assessment of aging effects on soil liquefaction

Soil Dynamics and Earthquake Engineering

Resilience Evaluation of Water Supply Networks against Seismic Hazards

Journal of Pipeline Systems Engineering and Practice, 2016

Liquefaction Potential Assessment of Pleistocene Beach Sands near Charleston, South Carolina

Journal of Geotechnical and Geoenvironmental Engineering, Oct 1, 2012

ABSTRACT Liquefaction potential of four Pleistocene beach sand deposits in the Greater Charleston... more ABSTRACT Liquefaction potential of four Pleistocene beach sand deposits in the Greater Charleston area, South Carolina, is assessed. The assessment is based on a review of 51 sites of conspicuous craterlets and horizontal ground displacement that occurred in beach sand deposits during the 1886 Charleston earthquake and an analysis of 82 seismic cone penetration tests with pore-pressure measurements. Of the 51 ground failure sites, 23 are associated with the Ten Mile Hill beds; 13 with the Wando Formation; 13 with the Silver Bluff terrace and younger deposits that lie adjacent to the harbor, rivers, and creeks; and two with the Ladson Formation. Liquefaction potential is analyzed using the seismic cone data with and without correction for age-related processes (diagenesis) and then expressed in terms of the liquefaction potential index (LPI). Probability curves are developed from the LPI calculations for different earthquake ground-shaking parameters. The probability curves for the Wando Formation overpredict liquefaction potential when no corrections for diagenesis are made. When corrections for diagenesis are made, the probability curves for all four sands generally agree with the observed field behavior. DOI: 10.1061/(ASCE)GT.1943-5606.0000686. (C) 2012 American Society of Civil Engineers.

Subsurface investigation of a liquefaction-induced lateral spread, Thousand Springs Valley, Idaho. Final report

ABSTRACT

Index Properties-Based Criteria for Liquefaction Susceptibility of Clayey Soils: A Critical Assessment

J Geotech Geoenviron Eng, 2007

ABSTRACT The Cooper marl in Charleston, S.C., a deep layer of clayey soils approximately 5-21 m b... more ABSTRACT The Cooper marl in Charleston, S.C., a deep layer of clayey soils approximately 5-21 m below the ground surface, is generally recognized as nonliquefiable material. Data from field cone penetration tests and laboratory tests of samples taken from the Cooper marl are used to investigate the adequacy of index properties-based criteria for assessing liquefaction susceptibility of clayey soils. In particular, the criterion based on soil behavior type index (I-c) and that based on Atterberg limits are examined. The results show that the Atterberg limits-based criterion adequately reflected the characteristics of the marl, whereas the I-c-based criterion erroneously identified the marl as being liquefiable. A possible reason for the deficiency of I-c and a modification to overcome this deficiency are presented.

Ground Freezing and Sampling of Pleistocene Sand near Charleston, South Carolina

Journal of Geotechnical and Geoenvironmental Engineering, Dec 16, 2013

ABSTRACT

Correcting Liquefaction Resistance of Unsaturated Soil Using Wave Velocity

Journal of Geotechnical and Geoenvironmental Engineering, May 16, 2012

ABSTRACT

Liquefaction-induced ground failure: a study of the Chi-Chi earthquake cases

Engineering Geology, 2004

The 1999 Chi-Chi, Taiwan earthquake caused great destruction to buildings, bridges, and other fac... more The 1999 Chi-Chi, Taiwan earthquake caused great destruction to buildings, bridges, and other facilities, and a death toll of more than 2400. Lessons should be learned from this event, which, albeit disastrous, represents a rare full-scale experimentation in geotechnical engineering and related fields. Of particular interest to geotechnical engineers is the phenomenon of soil liquefaction that caused significant damage to buildings, lifelines and harbor facilities. These liquefaction phenomena, in the forms of sand boils, lateral spreads, tilting and settlement of buildings, and ground settlement, were observed in the Chi-Chi event. Shortly after the earthquake, an extensive field investigation in the Yuanlin area, including in situ tests and laboratory tests, was conducted by Moh and Associates and other parties. These in situ and laboratory tests along with ground performance observations form the basis for the present study. In this paper, 24 cases of ground performance in the areas that suffered the most from liquefaction are studied. The ground performance in selected cases of the 24 cases is accounted for through a series of liquefaction analyses. The analysis of the potential of liquefaction and ground failure is performed using Cone Penetration Test (CPT) data. The results of the analyses show that the field observations of ground performance in the Yuanlin area in the Chi-Chi event can be accounted for satisfactorily using the evaluation procedure by Ishihara (Ishihara, K., 1985. Stability of natural deposits during earthquakes.

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Modeling Dynamic Properties of South Carolina Coastal Plain Sediments for Ground Response Analysis

Geo-Congress 2022

Modeling Dynamic Properties of Rock in South Carolina for Seismic Ground Response Analysis

Geo-Congress 2022

Development of Site Amplification Factors for Reference Outcrop Site Conditions in the State of South Carolina

Geo-Congress 2022

Ground Motion Characteristics Based on Type of Input Motion and Spectral Matching Technique for South Carolina

Geo-Congress 2022

Modeling the Response of a Pleistocene Sand during In Situ Liquefaction Testing

Ground improvement techniques for liquefaction remediation near existing lifelines

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Assessing Probability-based Methods for Liquefaction Potential Evaluation

Journal of Geotechnical and Geoenvironmental Engineering, 2002

... However, the latter comparison is only approximate because different data sets were used in t... more

Risk-based liquefaction potential evaluation using standard penetration tests

Canadian Geotechnical Journal, 2000

Liquefaction Resistance of Soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils

Journal of Geotechnical and Geoenvironmental Engineering, 2001

Download

Predicting Shear-Wave Velocity from Cone Penetration Resistance

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Peak Shear Strength and Dilatancy of a Pleistocene Age Sand

Journal of Geotechnical and Geoenvironmental Engineering

At-Rest Lateral Stress Coefficient in Sands from Common Field Methods

Journal of Geotechnical and Geoenvironmental Engineering

State of the art in the assessment of aging effects on soil liquefaction

Soil Dynamics and Earthquake Engineering

Resilience Evaluation of Water Supply Networks against Seismic Hazards

Journal of Pipeline Systems Engineering and Practice, 2016

Liquefaction Potential Assessment of Pleistocene Beach Sands near Charleston, South Carolina

Journal of Geotechnical and Geoenvironmental Engineering, Oct 1, 2012

Subsurface investigation of a liquefaction-induced lateral spread, Thousand Springs Valley, Idaho. Final report

ABSTRACT

Index Properties-Based Criteria for Liquefaction Susceptibility of Clayey Soils: A Critical Assessment

J Geotech Geoenviron Eng, 2007

Ground Freezing and Sampling of Pleistocene Sand near Charleston, South Carolina

Journal of Geotechnical and Geoenvironmental Engineering, Dec 16, 2013

ABSTRACT

Correcting Liquefaction Resistance of Unsaturated Soil Using Wave Velocity

Journal of Geotechnical and Geoenvironmental Engineering, May 16, 2012

ABSTRACT

Liquefaction-induced ground failure: a study of the Chi-Chi earthquake cases

Engineering Geology, 2004

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Influence of age on liquefaction resistance of Holocene alluvial and marine soils in Christchurch and Kaiapoi, New Zealand

by Barnabas Bwambale and Ronald Andrus

Proceedings, 3rd International Conference on Performance-based Design in Earthquake Geotechnical Engineering (PBD-III) in Vancouver, BC, Canada, 2017

The influence of age on liquefaction resistance of Holocene alluvial and marine soils in Christch... more The influence of age on liquefaction resistance of Holocene alluvial and marine soils in Christchurch and Kaiapoi, New Zealand is characterized in this paper using published results of investigations in four areas (i.e., Kilmore Street, Gainsborough Reserve, Riccarton Road, and Kaiapoi). Much of Christchurch and Kaiapoi experienced minor to severe liquefaction during the 2010-2011 Canterbury earthquake sequence. Ratios of measured small-strain shear wave velocity to estimated small-strain shear wave velocity based on penetration resistance (MEVR) determined for the critical layers in the four areas agree well with the study by McGann et al., and are similar to ratios computed for recently liquefied deposits in other areas of the world. Deposit resistance correction factors to account for aging processes (KDR) determined for the four areas also compared well with factors determined for deposits in other areas of the world. These findings support the use of MEVR and KDR for accurate site-specific liquefaction assessment and performance-based design.

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Liquefaction resistance of Pleistocene loess- colluvium deposits near Christchurch, New Zealand

by Barnabas Bwambale and Ronald Andrus

Proceedings, 3rd International Conference on Performance-based Design in Earthquake Geotechnical Engineering (PBD-III) in Vancouver, BC, Canada, 2017

The liquefaction resistance of Pleistocene loess-colluvium deposits near Christchurch, New Zealan... more The liquefaction resistance of Pleistocene loess-colluvium deposits near Christchurch, New Zealand is evaluated in this paper. Permanent horizontal ground displacements up to 0.35 m occurred at several locations in these moderately sloping deposits during the 22 February 2011 Christchurch earthquake. Although sand/silt boils formed in the adjacent level-ground Holocene alluvium, none has been connected to the loess-colluvium. Computed ratios of measured shear wave velocity to estimated shear wave velocity based on penetration resistance (MEVR) are generally much greater than 1.0 for the loess-colluvium, which is higher than ratios obtained for the Holocene alluvial/marine sediments beneath Christchurch. Liquefaction resistance is evaluated using the liquefaction potential index (LPI) method. Computed values of LPI without correction for aging processes range from 25 to 48, which incorrectly suggest severe liquefaction in the loess-colluvium. The correction factor necessary to match predicted and observed ground behavior ranges from 2.4 to 3.4. These results are in good agreement with the MEVR-based correction relationship developed by Hayati and Andrus from a global database.

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