Standard Penetration Test Data Research Articles

Probabilistic Analysis of Local Liquefaction Potential Based on Spatial Variability of SPT Data

In this paper, the spatial distribution of liquefaction potential is estimated using in-situ data from the Standard Penetration Test (SPT). For this purpose, a case study of a liquefiable soil at the Azad University of Qeshm is selected in the numerical modeling. After conducting the site investigation and determining SPT results at four boreholes, two distinct modeling approaches are implemented to evaluate the Liquefaction Potential Index (LPI) at the considered site; In the first method, the conditional random field for SPT data is generated in a layer-by-layer strategy and then, the LPI is obtained using a SPT-based empirical relations at each elemental column. On the other hand, in the second method, the LPI is first determined at each borehole location and then, this parameter is adopted as a stochastic variable in the construction of surficial conditional random field. It can be concluded that both approaches are able to capture the varying severity levels of liquefaction at most locations across the area of study. However, the comparison shows that using the first approach results in a more fluctuated LPI results with almost the same extremum values.

Numerical prediction of settlement due to the Pohang earthquake

On 15 November 2017, an earthquake with a magnitude of 5.4 caused geotechnical damage over a wide area of Pohang, South Korea. In this study, the UBCSAND constitutive effective stress model is calibrated by cyclic direct simple shear (CDSS) tests conducted on a type of sand from liquefied paddy fields at Pohang under confining stresses of 100 and 200 kPa. The calibrated UBCSAND model is then used to assess the liquefaction and calculate the ground settlement based on standard penetration test (SPT) data near the epicenter of the Pohang earthquake. The liquefaction characteristics from the UBCSAND model matched those from laboratory tests. According to the numerical results, liquefaction mostly occurred within the uppermost 10 m, and ground surface settlement from excess pore water pressure dissipation varied from 3.86 to 10.95 cm. These settlements were higher than the surface displacement estimated by satellite image analysis with interferometric synthetic aperture radar (InSAR) and lower than the ground subsidence observed solely by visiting the sites.

In Situ Shear-Wave Velocity Assessment at the Delaney Park Downhole Array, Anchorage, Alaska

Abstract The shear-wave velocity (VS) in soil is an important parameter to characterize dynamic soil properties. The Delaney Park downhole array was deployed in 2003 without measuring the shear- and compression-wave velocity (VS and VP) profiles. Thornley et al. (2019) measured the VS and VP profiles using the downhole method after the sensor was removed from the 61 m borehole with casing in the array. However, the waves propagating along the casing wall may have a great influence on the recognition of the first arrival of waves propagating in the soil. Using horizontal and vertical components of weak-motion data of eight local earthquakes recorded by the array, in situ VS and VP profiles were assessed by the seismic interferometry based on deconvolution, respectively. The results are as follows. The VS and VP profiles computed by this study and measured by Thornley et al. (2019) are in relatively good agreement at a depth of 10–45 m and at a depth of 30–45 m, respectively, and in very poor agreement at other depths. The average VS profiles computed by this study are more consistent with the derived VS from the standard penetration test data at the site with slower near-surface velocities relative to the downhole logging analysis. There are strong anisotropy in the strata below 45 m and weak anisotropy with various degrees at various depths in the strata above 45 m.

REVIEW OF BEARING CAPACITY AND SETTLEMENT OF PILE FOUNDATION IN PORT INFRASTRUCTURE

ABSTRACTThe rapid infrastructure development is one of the indicators on the country economic progress. Indonesia as one of the largest archipelagic countries in the world, should be prioritized the port infrastructure to support the maritime. One of the government’s solutions is infrastructure development of Kuala Tanjung port. This research analyzed bearing capacity and settlement of single and group pile foundation on port infrastructure of Kuala Tanjung so it is known that the port is safe to use. The data used are Standard Penetration Test data with soil stratigraphy that is clay and sand. The type of foundation used is Concrete Spun Pile 1000 mm and 600 mm with a pile length of 36 meters. The data are then analyzed by manual calculation and Allpile 6.5E program based on Reese method and methods such as Vesic and Converse-Labarre. The results showed that single pile foundations of 1000 mm and 600 mm each had allowable capacity (Qall) 492.78-538.81 ton and 110.65-128.31 ton, with vertical load (Q) of 330.90 ton, settlement 0.56-1.17 cm and 3.32-3.64 cm, lateral deflection 27.50 cm and 94.90 cm. While the 1000 mm and 600 mm pile group foundations respectively have Qall 8717.31-10796.29 tons and 2059.25-2566.32 tons, with Q of 6618 tons, settlement 0.56-1.68 cm and 3.32-3.64 cm, lateral deflection of 2.49 cm and 19.49 cm. The conclusion of the research indicates that the safe pile foundation used is 1000 mm group pile foundation. Keywords: Bearing Capacity; Foundations; Pile Foundation; Port Infrastructure; Settlement

Correlation Between SPT and PMT for Sandy Silt: A Case Study from Kuala Lumpur, Malaysia

In this study, the pressuremeter modulus (EM) and the unload–reload modulus (Eur) consisted of a wide range of data were correlated to blow counts (N60) using a maximum of 50 blows/300 mm and the extrapolated N60 of 300 blows/300 mm. A 3D model and statistical analysis were used to provide relevant justifications for the selection of this extrapolation method, considering that N60 was limited to 50 blows. In generating a 3D model, the N60 profile was developed using the inverse distance weighting method for predicting unsampled data between boreholes. Correlations were established for the sandy silt soil type that was observed as the dominant lithology in the Klang Valley Mass Rapid Transit line 1 project in Kuala Lumpur, Malaysia. A total 52 pressuremeter test and standard penetration test data pairs were obtained at depths ranging from 6 to 41.7 m within the Kenny Hill Formation (KHF) and the contact zone between the KHF and the limestone formation. This contact zone has shown distinct geological features with the characteristic of a lower N60 value underlying stiff strata. According to the EM/Eur ratio, the maximum value of 7 indicated that this zone is unpredicted in initial and unload–reload stiffness compared to the non-contact zone (the KHF only), with a maximum ratio of 3. Therefore, separate correlations were established to distinguish these zones. Strong correlations between N60 and EM were identified by splitting these zones. The proposed correlation was then compared with the previous research.

A Simple and Sustainable Prediction Method of Liquefaction-Induced Settlement at Pohang Using an Artificial Neural Network

Conventionally, liquefaction-induced settlements have been predicted through numerical or analytical methods. In this study, a machine learning approach for predicting the liquefaction-induced settlement at Pohang was investigated. In particular, we examined the potential of an artificial neural network (ANN) algorithm to predict the earthquake-induced settlement at Pohang on the basis of standard penetration test (SPT) data. The performance of two ANN models for settlement prediction was studied and compared in terms of the R2 correlation. Model 1 (input parameters: unit weight, corrected SPT blow count, and cyclic stress ratio (CSR)) showed higher prediction accuracy than model 2 (input parameters: depth of the soil layer, corrected SPT blow count, and the CSR), and the difference in the R2 correlation between the models was about 0.12. Subsequently, an optimal ANN model was used to develop a simple predictive model equation, which was implemented using a matrix formulation. Finally, the liquefaction-induced settlement chart based on the predictive model equation was proposed, and the applicability of the chart was verified by comparing it with the interferometric synthetic aperture radar (InSAR) image.

Liquefaction Hazard Mapping Based on LPI (Liquefaction Potential Index) At Jepara, Indonesia

Liquefaction is a phenomenon of loss of strength of the soil layers caused by earthquake vibration. Liquefaction causes the soil to be in a liquid – like state, especially on sandy soil. Analysis of liquefaction potential was performed by using the semi-empirical method by calculating the Safety Factor (SF) based on Standard penetration Test (SPT) and Cone Penetration test (CPT) data. After the SF value was obtained, then the Liquefaction Potential Index (LPI) was calculated to determine the level of potential liquefaction in the study area to further produce a liquefaction potential map based on the liquefaction potential index. Based on the results of the calculation of the LPI, the level of liquefaction potential in the study area was very low when the earthquake magnitude is 5 Mw because the Liquefaction Potential Index (LPI) = 0. When the earthquake magnitude is 6 Mw, 7 Mw, 8 Mw, and 9 Mw, most of the investigation area has low potential level and there are some points that a high potential level.

Potential study of the liquefaction hazard at the reclamation development site of I Gusti Ngurah Rai airport, Nusa Dua region, province of Bali

I Gusti Ngurah Rai Airport is an international airport in the Province of Bali with high traffic. The government of the province encouraged the airport services company to increase the airport’s capacity by expanding the aircraft apron. To initiate this project, land reclamation had been carried out on the west side of the existing apron. However, a sea wall was used for protecting the reclamation area from attack by waves. This case study of the reclamation area is intended to investigate its geotechnical aspect, in which the potential of liquefaction is necessary to be evaluated. The liquefaction is quantified by referring to CPT (cone penetration test) and SPT (standard penetration test) data. Analysis results of the reclamation area at location 1 (CPT testing) and location 2 (SPT testing) showed occurrences of the liquefaction hazard, where the FS (safety factor) was found to be less than 1. This means that soil improvements, such as utilizing a vibro-compaction method, are required. The steps of the vibration method are considered as the simplest method, particularly for compaction of sand material in the reclamation area. The criteria evaluation standard for the compaction is Dr (relative density) of greater than or equal to 70%.

Comparison of direct SPT method for calculating axial capacity of piles in Jakarta Area

Estimating axial capacity of piles using Direct Method are still considered as challenges these days. Estimation mainly achieved after construction is done and field method such as static load test or PDA are used for calculating axial capacity of piles in real field cosnditions. This paper discussed estimation from 8 building project cases from Jakarta and Depok that have complete standard penetration test data and field calculations (static load test & PDA). The main objectives are to observe and correlate the results between every Direct Methods and field methods and to obtain which Direct Method is the most efficient to use for estimating axial capacity of piles in Jakarta area. Direct Methods that are used are Meyerhoff, Shariatmadari, Decourt, Aoki, and Robert. Calculation results showed that the most efficient standard penetration test method is that proposed by Decourt with average result of comparison between estimated axial capacity of piles and field calculation is roughly 1.03. The most underpredicted between every standard penetration test method is the one proposed by Aoki de Alencar with roughly 92% underprediction ratios and the largest overpredicted method is proposed by Shariatmadari with roughly ratios of 56%.

STUDI EVALUASI PONDASI TIANG PANCANG (SPUN PILE) DENGAN PONDASI TIANG BOR (BORED PILE) PADA GEDUNG KANTOR PEMERINTAH KABUPATEN LAMONGAN

Foundation planning must be done carefully and correctly. The planning of this foundation aims to compare the axial forces acting with the carrying capacity of the foundation between the original foundation that spooked the spune pile and bored pile on the construction of the Lamongan Regency Government office building to obtain safe control. The carrying capacity of the foundation is planned to use Standard Penetration Test (SPT) data. The initial calculation of loading analysis includes dead load, live load and earthquake. These expenses are combined then analyzed with the Staad.Pro program. The reduction calculation uses a method of reduction in clay. Calculation of pile cap and foundation reinforcement using SNI 1726-2012. The output of the Staad.Pro program is obtained axial force in the column that is reviewed at 1260 kN. Carrying capacity of a single pole pole diameter of 40 cm with a depth of 20 m obtained compressive strength of 431.49 kN. Taking into account the efficiency figures obtained group carrying capacity (Qg) of 1715.52 kN> 1260 kN, so that it meets the requirements. The flexural reinforcement D16-125 mm is planned to hold the moment in the pile cap which occurs at 211.6 kN-m. The decrease in total (St) is the immediate total decrease (Si) and the decrease in consolidation (Sc) which is 1.673 <15 cm. The decrease in total (St) on the group pole meets the permitted conditions for the building based on the Geotechnical RSNI.

Correlation of geoelectrical and geotechnical parameters of data obtained from geophysical survey conducted at Ahmadu Bello University Phase II, Zaria, Nigeria

Vertical electrical soundings (VES) and standard penetration test (SPT) were carried out at Ahmadu Bello University Phase II, Zaria, Nigeria, with the aim of correlating between transverse resistance (T) and number of blows per counts (N-value) for foundation studies. Two (2) SPT and VES using Schlumberger electrodes array, were conducted within the study area. The VES data acquired from the field were processed and interpreted using AGI earth imager 1D software. Borehole data of exact point, where the VES was carried out were used for calibration. The results obtained from the VES depicts that the depth to basement values ranges between 6.5 and 8.0 m which agree with the borehole data obtained from the SPT results. The results of resistivities and thickness obtained from the VES curve were used to compute transverse resistance. The transverse resistance was used to correlate with the N-values obtained from SPT data. It was observed that the correlation of transverse resistance and N-value was linear and highly positive. The linear relationship that was established between the two parameters can be used to determine the soil strength at any point within the area of study.

Estimation of autocorrelation distances for in-situ geotechnical properties using limited data

A simultaneous estimation of the vertical and horizontal autocorrelation distances (ACDs) for geotechnical properties under the condition of limited data (fewer than one hundred data points) is not well studied. This paper evaluates the performance of the maximum likelihood estimator (MLE) in estimating autocorrelation distances using some simulated data. The effect of the autocorrelation structure on the accuracy of ACD estimation is also investigated. It is found that MLE may produce highly biased estimations if limited data are available. Hence, a clustered borehole layout scheme and a resampling method are proposed to improve the estimation accuracy. The methods are illustrated using some simulated data, standard penetration test (SPT) data and cone penetration test (CPT) data. It is found that the clustered borehole layout scheme and resampling method yield more accurate estimations of ACDs in analyses using both the simulated data and real data.

Correlations of SPT, CPT and pressuremeter test data in alluvial soils. Case study: Tabriz Metro Line 2, Iran

The Menard pressuremeter modulus (Em), limit pressure (PL), shear modulus (G) and subgrade reaction modulus (Ks) can be obtained by using the pressuremeter test, and are needed as parameters to obtain the geotechnical parameters for foundation design and to determine the ultimate bearing capacity in engineering projects. In this article, correlations of Menard pressuremeter tests (PMTs) with standard penetration tests (SPTs) and cone penetration tests (CPTs) are obtained as a consequence of the extensive geotechnical investigation performed in alluvial soils of the Tabriz Metro Line 2, Iran. A total of 85 boreholes with depths of 20–40 m were drilled, and the three mentioned tests were performed at varying depths. Correlations were carried out separately for silty clay (CL), clayey silt (ML) and silty sand (SM) soils, respectively. Statistical correlations between Em, PL, G and Ks from the PMTs were performed with the corrected SPT numbers (Ncor). In addition, relationships between the limit pressure (PL) from PMTs and cone resistance (qc) from CPTs were determined for fine-grained and coarse-grained soils. Attempts were also made to correlate PL with Em, and Em/PL ratios. The results of this investigation indicated acceptable experimental regression relationships between these parameters. The comparisons between the measured and the predicted values of Em and PL obtained herein with those estimated from other equations that have been proposed by other researchers revealed that they are compatible. It can be concluded that the proposed relationships for fine-grained and coarse-grained soils can be utilized to determine Em, PL, G and Ks from the Ncor values and PL from the qc values.

Cluster analysis for the determination of the undrained strength tendency from SPT in mudflows and residual soils

The standard penetration test (SPT) remains one of the most commonly used field tests to obtain the shear strength properties of soils, the undrained strength (cu) being one the most SPT-N-correlated parameters for geotechnical applications. The overall N-value-cu correlations show a direct relationship between them, characterized by presenting an equation formed by a constant value multiplied by N. More recently, the use of cu in geotechnical engineering has been of great interest in the evaluation of the influence of the undrained strength variability with depth on slope stability analysis. Therefore, an evaluation of the variability with depth of the N-value is made according to the geological origin. However, the (N1)60 values obtained from the SPT have different limitations due the possible “outside of tendency” data known as outliers caused by random factors such as: rock fragments content, weak zones and variations in the state of weathering, which may ultimately affect the estimation of the cu function with depth. Therefore, a cluster analysis of the SPT data was performed in order to identify the values that affect the best-fitting mathematical SPT-N function with depth. These analyses were implemented to the (N1)60 values obtained from multiple SPTs in two distinct geological units, mudflows and residual soils, in order to study the influence of the geological origin in the SPT and, therefore, of the shear strength tendency with depth. It was found that the best clustering method to identify the SPT tendency and the state of weathering in residual soils is the Ward method. For mudflows, the best cluster algorithm is the single method; however, it is concluded that for large areas, the use of a unique cluster method is not recommended. For most projects, the undrained shear strength showed a nonlinear tendency with a squared Z (where Z is the depth in meters) function being common among all geologies. The function gradient for residual soils is about twice when compared with that of the mudflows, mainly due to the overburden pressure and to the decrease in the state of weathering with depth, which increases shear strength in the former type of soils.

The Identification of Hard Bottom Surface Structure using Correlation of Geoelectrical Resistivity Methods and SPT Data as Preliminary Studies for Laying the Foundation at Passing Cross Sumatera Toll Road, South Lampung Station

The planting of the Upper pass foundation on the Sumatera toll road construction project in South Lampung requires proper planning in terms of both technical and safety aspect. Generally, in principle, the foundation should be able to reach soil layers, or in case the hard soil is not easily found, the compaction or soil recovery. To find out the geological condition below the soil surface, related to the planting and construction of the foundation, it is necessary to investigate and identify the geological structure of the area. The method used to identify the subsurface methods and the Standard Penetration Test (SPT). The resistivity geoelectrical method utilizes a variety of resistivity values for each rock, while the SPT method uses the amount of resistance (N) per depth of soil penetration in its process. The result of the investigation using these two parameters will then be correlated with the geological conditions of the research field to determine the hard surface structure. Hard layer on the research field had resistivity values above 250 Ω and N-SPT values are above 50, identified as a fine sand layer containing gravel breccia sandstone and granodiorite stones. The subsurface hard layer can be found from a depth of 0-25 meters at the research field.

Screw driving sounding test; a new technology in soil investigation work particularly for soft soil

Screw Driving Sounding (SDS) test has been developed in Japan as the improved version of the Swedish Weight Sounding (SWS) test. The development of SDS is to reduce the drawbacks of the SWS with the integration of rod friction estimation. Deep boring with Standard Penetration Tests (SPT) together with soil sampling for laboratory tests have been the common procedure for determining the subsurface soil profile and geotechnical engineering properties. However, the SPT which is associated with deep boring, uses high fossil fuels, needs high skilled workers and expensive. This paper presents the SDS technology and the SDS test results in comparison with the existing SPT data from six (6) selected sites in Malaysia. Results show that there is a strong correlation between SPT and SDS data, and the soil profile is better identified using SDS than the SPT. It is predicted that SDS test has the potential to replace conventional soil investigation methods, particularly in soft soils area. It is not just fast, cheap and does not require highly skilled workers but SDS tests supports green technology and sustainability in construction. Quality results are guaranteed from the usage of Industrial Revolution 4.0 technology through automation in testing and making use of the cloud computing to manage the data.

An improved global zonation method for geotechnical parameters

Spatial prediction or interpolation of geotechnical parameters is a vital step in the designs or reliability analyses of geotechnical structures. Existing studies involving spatial predictions of geotechnical parameters ignore the distinction of spatial variabilities in zones along a horizontal direction, such as zones along a subway line. This study proposes a zonation method to differentiate the horizontal zones with different characteristics of spatial variabilities. Some uniaxial compressive strength and standard penetration test data are used to illustrate the proposed zonation method and the effect of zonation on the prediction accuracy. The results show that the proposed method is effective in distinguishing zones with different spatial variabilities and the improved zonation method facilitates more accurate predictions of unknown parametric values.

A Comparison between Drilling and Standard Penetration Test (SPT) Data to the Electrical Resistivity Sounding with Schlumberger Configuration in UNS Area

<p>The geophysics test using electrical resistivity method has been conducted in the area of UNS Campus to indicate the lithological of subsurface. This method is categorized as a Non-Destructive Test (NDT) due to the data acquisition is done at the ground level and no destruction during the test, which is more advantageous than destructive method such as drilling and SPT test. This study was performed with Schlumberger configuration in three location by electrical resistivity sounding. The acquisition data uses Resistivity meter OYO 2119 McOHM-EL with the track length is 100 m, while the data processing use IPI2Win to get a logarithmic graph between distance and resistivity and Origin to obtain graphic of resistivity and SPT. The result of this study indicates that electrical resistivity has a good correlation with SPT data. The electrical resistivity graph shows a linear increase along with increment of the depth, which is similar to the SPT graph. The slope difference at the first location is 2.44±1,197, the second location is 2.028±0.822, and the third location is 0.622±0.735.</p>

Pleistocene molluscan assemblage in the southern Coastal Plain of Rio Grande do Sul, Brazil: Implications in the evolution of a Barrier-Lagoon System

The Barrier-Lagoon System III is the better preserved Pleistocene depositional system in the southern Coastal Plain of the state of Rio Grande do Sul, Brazil. The origin of this unit is correlated to the sea-level highstand of the last interglacial stage, but so far very little is known about the evolution and stratigraphy of this unit due to the scarcity of outcrops. A fossil assemblage consisting of thousands of bivalve and gastropod shells were recovered from drilling holes and SPT (Standard Penetration Test) surveys performed at depths up to 17 m on that unit. The characterization of these fossils in addition to the analysis of the sediments and SPT data allowed to interpret the depositional setting of the fossil-bearing sediment as backbarrier deposits representing a retrogradational sequence characterized by lagoon bottom and margin facies superposed by sandy aeolian facies, covered by loess deposits. The fossil assemblage found in the lagoon bottom and margin deposits is dominated by bivalve and gastropod molluscs, mostly characteristic of open marine, shallow (≤30 m) environment, but including some Erodona mactroides and Anomalocardia brasiliana, bivalves typical of lagoon environments. The presence of species that do not currently live in the region suggests the influence of warmer coastal waters during the last interglacial stage. The good degree of preservation of a large part of the molluscan assemblage, with no signs of abrasion, bioerosion or incrustation, indicates short residence time at the sediment-water interface after death and disarticulation, followed by rapid burial below the Taphonomically Active Zone (TAZ). The presence of marine species together with species from low energy mixohaline environments indicates the transport of sediments and marine fauna to the backbarrier, which would have occurred during the transgressive phase of System III evolution. This process could have been related to increased storminess during the last interglacial, which promoted the transportation of large amounts of sediments and shells from the shoreface to the backbarrier through overwash and opening of ephemeral inlet channels.

Liquefaction severity mapping based on SPT data: a case study in Canakkale city (NW Turkey)

Soil liquefaction is one of the major causes of damage to buildings and structures during earthquakes. Very shallow groundwater table in Quaternary alluvial deposits and the seismic properties of a region can cause a significant damage to buildings and infrastructure dependent on liquefaction. Canakkale city is located in the first-degree seismic hazard zone according to the earthquake zone map of Turkey. A large part of the Canakkale settlement area is located on unconsolidated alluvium recently deposited by the Saricay River. In this survey, the liquefaction potential of the Canakkale settlement area was investigated based on the liquefaction severity index and liquefaction potential index for two possible earthquake scenarios with a moment magnitude (Mw) and peak ground acceleration (amax) of 7.5 and 319 gal and 7.0 and 222 gal, respectively. In addition, these two methods were analysed using the peak ground acceleration (amax = 141 gal) value measured at the Canakkale station during the 2014 Aegean Sea earthquake. Based on the results of the analyses, liquefaction susceptibility maps of Canakkale city were produced for different amax values. The study involved three stages: field work, laboratory testing, and generation of the liquefaction severity maps. Geotechnical boreholes at 151 locations were drilled and Standard Penetration Tests (SPT) performed. Thereafter, natural moisture content, unit weight, grain-size distribution, and Atterberg limits were determined by means of laboratory testing. Finally, Quaternary alluvial deposits in the study area were divided into five classes representing very low-to-very high liquefaction for three amax values.