Standard Penetration Test Research Articles

Integrated use of georadar, electrical resistivity, and SPT for site characterization and water content estimative

Geophysical methods are potent tools for geotechnical site characterization in a nondestructive way. They improve the extrapolation of punctual data from direct survey methods, allowing a fast and cost-effective evaluation of large areas. Ground Penetrating Radar (GPR) and DC electrical resistivity (ER) are the most requested methods for geotechnical and geoenvironmental applications. Their use, however, is usually uncoupled, with no sharing of information from one method to another to improve data interpretation. This case study illustrates the development of protocols and scripts in R© programming language for ER and GPR data analysis with Standard Penetration Tests (SPT) data to produce more accurate information on subsurface conditions concerning lithology, water content, and groundwater table (GWT) position. The SPT data were used to associate resistivity ranges with different soil lithologies and GPR pulse velocities for estimating the soil water content. Estimated water content values aided in interpreting ER data and locating the groundwater table. The contacts between layers in the radargrams allowed the refinement of the ER model, rendering 3D volumes for each soil layer in situ.

Model uncertainties of SPT, CPT, and VS-based simplified methods for soil liquefaction assessment

Simplified methods for assessing soil liquefaction potential based on the standard penetration test (SPT) are prevalent in practice and widely accepted by several seismic design codes. When encountering sites that have not been investigated using SPT, such as offshore sites or sites with a high level of gravel content, engineers can only substitute the methods based on piezocone penetration test data (CPT-qc methods) or shear wave velocity measurements (VS-based methods); however, these two approaches perform inconsistently with methods based on SPT data (SPT-N methods). As a result, this paper exploits the datasets consisting of SPT, CPTU, and in situ seismic test measurements from 13 alluvium sites in the Taipei Basin to compare the performance of prevalent SPT-N, CPT-qc, and VS-based methods. The discrepancies (uncertainties) of these methods are characterized as Gaussian distribution models, which is believed to be a feasible strategy for predicting equivalent results for SPT-N methods when SPT data are not available. Finally, the application of the proposed models to liquefaction potential index evaluation is demonstrated using a real case study.

Evaluation of Soil Liquefaction Using SPT Data at Boyolali Regency, Central Java

On 27 May 2006 at 05:54 local time, a major earthquake with a moment magnitude (Mw) of 6.3 occurred in Yogyakarta Province. This earthquake was widespread causing several damages in Yogyakarta Province and Central Java Province. One of the regencies in Central Java Province impacted was Boyolali Regency. This research aims to evaluate soil liquefaction based on the Standard Penetration Tests (SPT) in Boyolali Regency. Evaluation of soil liquefaction was necessary to minimize the damage as a preliminary in determining mitigation methods that can be applied. Besides Mw 6.3 earthquakes, according to SPT Data, several factors that triggered liquefaction were found in this study area such as a shallow groundwater table and the existence of a poorly graded sandy soil layer. The liquefaction was evaluated by comparing the Liquefaction Severity Index (LSI) and the Liquefaction Risk Index (LRI) using the simplified method. Based on the analysis, the result showed that Boyolali Regency had a value of LSI in the range of very low until low severity and a value of LRI in the range of low until the high risk.

Estimating of Post-liquefaction Settlement Based on SPT Data in Klaten Regency, Central Java

A strong earthquake with Mw 6.3 occurred in Yogyakarta on May 27, 2006, causes of damage to DI Yogyakarta Province and Central Java Province, including Klaten Regency. The geological stratigraphy consists of volcanic breccias, lava and tuff in this area and generally shallow groundwater levels, which can trigger liquefaction. The potential liquefaction analysis in this study uses Standard Penetration Test (SPT) data carried out in 3 districts, namely Delanggu, Polanharjo, and Karanganom District uses Idriss-Boulanger method. The peak ground acceleration was calculated by Next Generation Attenuation (NGA) method using data obtained from the Pacific Earthquake Engineering Research (PEER) Center database. The peak ground acceleration that causes liquefaction in this study is at least 0.29 g in bedrock. All areas indicated potential liquefaction with varying depths. Polanharjo District is the most susceptible to potential liquefaction. The method proposed by Zhang estimates post-liquefaction settlement in this study from 3.3 – 42.4 cm (light to extensive damage) in Klaten Regency. Based on the results, further mitigation studies are needed in Klaten Regency to minimize settlement that will occur due to liquefaction. This study is required in planning the construction of toll road in Klaten Regency.

Strength and consolidation index parameters of stabilise clay soil using scrap rubber tyre

Scrap rubber tyres are one of the synthetic fibre materials that can be used as a soil stabilizer. This study looks into the effects of scrap rubber tyres as a soil stabiliser on clay soil. Soil samples were collected in Kota Kinabalu, and the scrap rubber tyre was passed through a 2 mm passing sieve. Three experimental tests were carried out: compaction, consolidation, and an unconfined compression test (UCT). During the compaction test, the maximum dry density (MDD) and optimum moisture content (OMC) parameters were determined using the proctor standard penetration test. The shear strength of all soil samples was determined using UCT. The consolidation test also looks at the compressibility index and swelling index. Four soil sample configurations were prepared, one as a control sample and three with different soils mixed with varying percentages of scrap rubber tires: 1.5%, 2%, and 5%. This study investigates the degree of compaction, shear strength, settlement behaviour (compressibility), and swelling behaviour of scrap rubber tyres as a soil stabiliser. According to the findings, the optimal amount of scrap rubber tyres as a stabiliser that could improve the properties of clayey soil is 2%.

Probabilistic and deterministic-based approach for liquefaction potential assessment of layered soil

In the present study, deterministic and probabilistic approaches have been used for the assessment of liquefaction potential of ground during an earthquake. The deterministic approach was used to analyze and assess the liquefaction of loose saturated river bed deposit with emphasis on two benchmark locations. A wide range of earthquake data in the form of peak ground acceleration (PGA) values of 0.18 g, 0.37 g, 0.6 g and 0.75 g was used as input motions. The dynamic properties of soil were evaluated using standard penetration test (SPT) data obtained from the bore logs. The shear stress induced within soil deposit due to the seismic excitation was calculated in the form of cyclic stress ratio (CSR) and cyclic resistance ratio (CRR) in order to calculate the factor of safety (FOS) against liquefaction. In addition, liquefaction potential index (LPI) and probability of liquefaction (PL) were also calculated using input motion. It was observed, based on the probability analysis and liquefaction indices, that the shallow layer soil profile is safe against liquefaction, whereas deep layer soil profile is unsafe.

Assessment of Liquefaction Hazard and Mapping Based on Standard Penetration Tests in the Long Beach and Tuzla Regions of Cyprus

Cyprus is the third largest and populated island in the Mediterranean Sea, and is still rapidly expanding. Significant infrastructures, such as hotels, educational institutions, and large residential complexes, are being built. Historically, 15 destructive earthquakes were reported on Cyprus from 1896 to 2019 that caused structural damages and casualties. In this study, the liquefaction potential of Tuzla and Long Beach on the east coast of Cyprus is estimated using the standard penetration test (SPT) data from more than 200 boreholes at different locations at the sites. The overall results are presented in a liquefaction potential index obtained from the factor of safety (F.S.) coefficient. Both study areas are susceptible to liquefaction. Thus, liquefaction potential maps are prepared to identify hazards in Tuzla and Long Beach. Additionally, the average factor of the safety line was introduced for both sites to create a correlation between the liquefaction area and F.S. values of every borehole. The adopted approach precisely provides the liquefiable regions when compared with historical evidence, CPT measurements, surface geology aspects, and geospatial data. Additionally, the results prove that the liquefaction potential must be considered during the design stage of new infrastructure in these areas.

Geological-geotechnical investigations of the historical Diriyah urban zone in Riyadh, Saudi Arabia: an integrated approach

One hundred seventy geotechnical boreholes, two geo-seismic profiles of multichannel analyses of surface waves (MASW), and two geoelectrical cross-sections of electrical resistivity tomography (ERT) were carried out in the historical Diriyah urban zone. The borehole samples were analyzed for the geotechnical parameters of the standard penetration test (SPT N-value), the rock quality designation (RQD), and compressive strength (CS). Moreover, P- and S-wave velocities have been calculated. The measured SPT N-value has been corrected to amend the N60 parameter. According to the corrected N60, type, lithological, and soil profiles were divided into five distinct subsurface layers. It is indicated, for all recorded depths, these sediments become denser with depth where the values of N60 increase from 5 to 88 downward. According to grain size distribution, the major part of soil sites is composed of sand and varies from low to medium compressibility. The estimated RQD values range from 5 to 100 indicating rocks with significant variations in their geotechnical and physio-chemical characteristics. Furthermore, the compressive strength varies widely between 152.3 and 1,104.2 kg/cm2, which represents diverse geodynamic behavior under civil engineering constructions. Besides, the range of soil stiffness is indicated by the Shear-wave velocity (Vs) for soil layers, which varies from 171.3 to 456.2 m/s. According to the findings of the MASW profiles, the shear wave velocity is shown to be decreasing in MASW profile 1 between depths of 8 and 14 m, where the values range from 1,000 to 1,500 m/s, indicating a weak zone filled with secondary materials. But line 2 shows how the shear wave velocity decreased from depths of 5 m–11 m, where values ranged from 1,000 to 1,500 m/s, thus indicating a weak zone. The low resistivity zones in ERT cross-sections, which are found at the same depths in MASW profiles, are well associated with these findings. It can be concluded that there are a number of weak zones with varying depths, shapes, and dimensions found in the historical Diriyah urban zone’s near-surface deposits that civil engineers, urban planners, and urban developers should consider before undertaking any construction or developmental work involving civil engineering.

The Effect of High Pore Water Pressure on Liquefaction Potential in Sidoarjo Mud Volcanoes (LUSI)

LUSI until now is still active and holds the potential for subsequent disasters due to the influence of high pore water pressure in the affected area. The presence of high pore water pressure will cause a decrease in effective stress and decrease in soil / rock strength. This type of subsequent disaster is closely related to the process of liquefaction which has the potential to occur with the addition of earthquake events. Analysis of liquefaction potential with empirical analysis on standard penetration test (SPT) based evaluation, with input of soil properties parameters, seismicity, and groundwater level parameters. The groundwater level parameter in the calculation will show a normal pore water pressure value in accordance with the depth of the water-saturated layer. Input of high pore water pressure parameters so far has not been done. CPT-u measurement data for pore pressure value input consists of 13 points of measurements was on the northern embankment, with the lowest level of stability. The input of these parameters will provide variations in the differences in the level of potential liquefaction in the study area. The result is changes occur in the decrease in the safety factor value ranging from 0.1-0.4 and the change in the liquefaction potential index (LPI) value from originally low to high, and originally high to very high. The anomaly input of pore pressure in CPT-u measurement results ranges from 40%-70% higher than normal pore pressure in the sand layer. Analysis of the potential for liquefaction in the study area showed that the results of the high-very high liquefaction potential in the northern and eastern research areas, and the low Liquefaction potential was in the southern and western areas.

Weathering of Volcanic Rocks in Baturappe Formation and Its Implications for Foundation Planning of Pamukkulu Dam, South Sulawesi, Indonesia

The presence of weathered volcanic rocks in Pamukkulu area is important in determining the location and construction of the Pamukkulu main dam and plinth structure. In general, volcanic rocks have poor geotechnical characteristics due to varying degree of weathering, influence of groundwater, and systematic joints produced by cooling lava. This study aims to study the type and quality of weathered rock around the main dam and plinth area. First, mapping of surface geology was carried out. To evaluate the degree of weathering, rock resistivity data is used around the main dam area. Whereas for the plinth area, the bearing capacity of soil/rock is evaluated using Plate Bearing Test (PBT) and Standard Penetration Test (SPT). Bearing capacity obtained from PBT that were carried out on rock surface can be used to interpret rock weathering. In addition to SPT, the coring from rock drilling was also evaluated using Rock Quality Designation (RQD). It was found that the rock up to 20 m depth are of poor quality. It is recommended that the poor-quality rock is removed until moderately dense rock layer is found.

Influence of Groundwater Table Fluctuation on Liquefaction Potential Analysis Using Cyclic Stress Approach

In addition to earthquakes, groundwater table (GWT) also contributes to uncertainty in liquefaction analysis, so it needs to be considered. This research was conducted by analyzing the liquefaction potential with a cyclic stress approach using standard penetration test data and cone penetration test data with varied GWT in a case study of building design in Sleman, Yogyakarta Special Region. The liquefaction safety factor (FS L ) was calculated to obtain the liquefaction potential index (LPI) and liquefaction severity index (LSI). Based on the survey results, the GWT ranges from -6 m to -8 m. Referring to the FS L , there are several soil layers that have liquefaction potential at all GWT variations. The shallower the GWT, the greater the LPI and LSI values at the same point will be. Changes in GWT from -8 m to -6 m cause changes in the LPI and LSI classifications at several points. Based on LPI classification, the location belongs to high to very high category at -8 m and -7 m GWT and very high category at -6 m GWT. Based on LSI classification, the location belongs to low category at -8 m GWT, and low to moderate category at -7 m and -6 m GWT.

ASSESSING SEISMIC SOIL LIQUEFACTION POTENTIAL USING MACHINE LEARNING APPROACH

The liquefaction vulnerability of soil is generally related to a few soil parameters which are ordinarily measured by laboratory tests on distributed and undistributed tests under distinctive test conditions. This study uses methods based on a standard penetration test to assess liquefaction criteria to appraise the liquefaction vulnerability for soil deposits of Chalus City placed in a high seismic area. To overcome the deficiencies of these experimental strategies an ANN-based model has been created utilizing the Artificial Intelligence technique to anticipate liquefaction. The proposed model is a function of the plasticity index, liquid limit, water content, and some other geotechnical parameters. Reliability index (β) and probability of liquefaction (PL) have also been determined for both the proposed methods for a superior understanding of their accuracies and strength. First-order second moment (FOSM) reliability analysis has been embraced in the present paper. The observation drawn from the study illustrates a reliable and conventional expectation rate of the regression as compared to the experimental strategy. A strong regression shown for assessing the liquefaction vulnerability, which is based on field test information for preparatory prediction, would be of extraordinary help within the field of geotechnical designing.

Validity of Juang's Method to Predict the Liquefaction Potential of the Soils of Sablette Algiers

This work presents a deterministic and probabilistic analysis of the liquefaction potential of soils. Soil liquefaction is a process leading to the total loss of shear strength of loose sands under seismic stresses by increasing pore pressure. It is accompanied by deformations. Certain factors related to the characteristics of the ground and the seismic excitation can significantly influence the appearance or not of the phenomenon. Empirical methods of liquefaction potential assessment are widely used. The probabilistic method has been widely used for estimating the probability of liquefaction. Initially, the uncertain parameters are modeled by normal random variables. A parametric study of the coefficients of variation of the random variables showed that the number of strokes (N1)60 of the SPT test is the parameter that has the greatest influence on the probability of liquefaction. This study focuses on the liquefaction potential by methods based on the results of the in-situ "Standard Penetration Test" Through the results obtained in this study of the site of Sablettes in Algiers, in general, there is a risk of liquefaction of the soil in the sandy layers, and we can say that the site studied has an average liquefaction potential. According to the classification of liquefaction potential proposed by Juang et al., (2012).

The use of screw driving sounding in soil assessment in Metro Manila, Philippines

A coastal portion of the Greater Metro Manila Area, Philippines, is situated primarily on Quaternary alluvium deposits, which are likely to liquefy. Liquefaction is a hazard that occurs when loosely packed, saturated sediments at or near the ground surface lose their strength, caused by an earthquake. Currently, the standard in determining the soil properties and liquefaction potential of a site is by using conventional geotechnical techniques such as the standard penetration test (SPT). However, this method has disadvantages in terms of cost, logistics and workforce. The screw driving sounding (SDS) test was developed to estimate equivalent SPT parameters such as N-value and fines content, which are then used for liquefaction analysis. This paper presents a comparative analysis between SDS and SPT in selected schools in the Greater Metro Manila Area, Philippines. Moreover, soil classification and site-specific liquefaction potential evaluation were also estimated using the data acquired from the SDS test. Overall, the results of the study prove that the SDS test is an effective alternative method for soil investigation and estimation of the liquefaction potential.

MATHEMATICAL MODELING OF THE COEFFICIENTS USED IN THE CORRELATION BETWEEN THE STANDARD PENETRATION TEST AND THE SOILS LOAD CAPACITY

In this article, the different calculations referring to the soil bearing capacity and its friction angle are analyzed. Specifically, from the sand when the Standard Penetration Test or also called S.P.T. is taken as a starting point.
 The modification of formula factors is proposed to obtain the friction angle of two different authors starting from a triaxial test. Several disturbed samples from the soil under study were taken both to carry out the triaxial test as well as the respective S.P.T tests from different points in the sector under study soil.
 Based on the data obtained, the respective correlation is carried out using R software, from which representative differences were found between the classical formulas and the research proposal.
 Effectively correlating the factor values used in the formulas commonly used in our calculations of both the admissible capacity of soils and the angle of friction are far from its actual capacity.
 Giving a new acquisition formula with a factor for the friction angle, representative in the treated soil.

Efficacy of Several Design Methods for Predicting the Axial Compressive Capacity of Piles

A variety of design methods for determining piles’ axial compressive load capacity are routinely employed in current practice. These range from methods specified in building codes to proprietary methods developed and employed by an assortment of engineering firms. In this study, the performance of eight commonly used design methods was evaluated using a database of 505 load tests and associated geotechnical design parameters compiled from Professor Olson’s database and that of the Iowa State Department of Transportation. The methods investigated included standard penetration test (SPT)-based methods, such as those recommended by the Federal Highway Administration (FHWA), U.S. Army Corps of Engineers, American Petroleum Institute, and Revised Lambda; and cone penetration test (CPT)-based methods such as those recommended by the Norwegian Geotechnical Institute, Imperial College, Fugro, and University of Western Australia. Pile capacities were calculated using APILE software and were compared with the measured capacities interpreted using the standard Davisson criterion and stored in the databases. The performance of all design methods was evaluated in relation to accuracy, precision, effect of soil type, diameter, and length. Both SPT and CPT methods exhibited similar accuracies, however, CPT-based design methods exhibited significantly better precision compared with SPT-based methods. All methods had shortcomings and appeared to work best under certain conditions, which are documented in this paper. The authors believe that this evaluation will permit practicing engineers and regulating bodies to better understand the efficacy of various design approaches in common use.

Penggunaan Data SPT dalam Penentuan Potensi Likuifaksi di Kota Solok

The area of West Sumatra which is at the confluence of 2 tectonic plates and 2 faults makes the area prone to earthquakes. One of the cities that has experienced an earthquake is Solok. One of the impacts of earthquakes is liquefaction events, namely the loss of strength of the sand layer due to increased pore water pressure. So that in planning construction in Solok it is necessary to review the potential for liquefaction in order to reduce construction damage and prevent liquefaction. To find out the potential for liquefaction as expressed by the value of the safety factor, it can be analyzed using standard penetration test data, namely N-SPT. The safety factor used in this study is the probability of 500 years and 2500 years. The results of the analysis of the safety factor obtained show that at each depth of the soil layer under review it has a value of < 1 so that the potential for liquefaction is quite high. The lowest safety factor is obtained at a depth of 4 – 6 m for a 500 year probability and 6 -7 m for a 2500 year probability which ranges from 0,12 – 0,16.

Correlation of Cohesion and Friction Angle Based on SPT-N Values: A Comprehensive Review

Soil parameters such as physical, chemical, and strength parameters play an important issue to classify the soil. Cohesion and friction angle are an important factor to understand the nature of the soil. Furthermore, standard Penetration Test (SPT) is one of the most common tests in the field and used to determine the strength of soil in the field prior laboratory tests. The variation in the properties of the soil in different regions, give differ values when using the standard methods, formulas, and correlations. In this paper, an overview of the methods and guidelines currently available in the scientific literature for evaluating the strength capacity of the soil, is reported. Further, important practical issues which contribute in the soil strength in different regions based on cohesion and friction angle used SPT are discussed. Moreover, the correlation results from the standard penetration test compared with those from cohesion and friction angle based on samples number and regions. Finally, the paper mentions the famous correlation in this domain and others from the standard code at USA, Jordan, Japan and UK. The compared results using guides from these standards showed big different, which let us to recommend that, these standards are not suitable for soil strength calculations due to different in the soil parameters from region to other.

Rapid impact compaction method as an alternative ground improvement technology in infrastructure project

Rapid Impact Compaction (RIC) is a ground improvement technology which have similarity with dynamic compaction method that most suitable applied to granular soil. The performance of Rapid Impact Compaction on the Airplane Refuelling Station Project Yogyakarta International Airport has been discussed in this paper. Two aspects of RIC performance observed in this are the increasing of shear strength as well as the depth of RIC influence though the changing of Standard Penetration Test (SPT) value. After treatment, the SPT value increase up to 300%, whereas the depth of influence of the Rapid Impact Compaction Method (RIC) is about up to 8 m. Based on the result, the formula can be generated i.e., Y = -0.0114 (X)2 +1.1702 (X) +12.875 where Y is the SPT value after treatment and X is the SPT value before treatment.

An Evaluation of a Marginal Land’s Geological Engineering Properties in Borikiri Sandfill, Port Harcourt Nigeria

Aim: The aim of this study was to assess the geological engineering properties of a marginal land in Borikiri Sandfill, Port Harcourt, Nigeria, using both field and laboratory investigations.
 Study Design: The study design involved the drilling of 4 boreholes and standard penetration tests to determine the soil profile and index properties such as particle size analysis, atterberg limits, and moisture content. Consolidation and triaxial tests were also performed to determine the values of the coefficients of permeability (k), volume compressibility (Mv), and consolidation (Cv).
 Place and Duration of Study: The Study was conducted in Borikiri Sandfill, Port Harcourt between February and May 2020.
 Methods: This study's methodology included field research, laboratory analysis, and testing. Drilling and conventional penetration tests were used to assess the soil profile. Laboratory tests such as particle size analysis, atterberg limits, and moisture content were used to determine the index characteristics. The values of permeability (k), volume compressibility (Mv), and consolidation (Cv) were also determined using triaxial and consolidation tests.
 Results: The results of the study showed that the soil profile consists of five stratigraphic sequences, with a top organic silty layer followed by a sandy layer, a dark plastic layer, a dark silty clayey sand, and a well-graded sand. The clays had an average Liquid limit (LL) of 45% and a Plastic Limit (PL) value of 23%. The values of k, Mv, and Cv were determined to be 2.1 x 10-7 m/s, 1.8 x 10-4–2.5 x 10-4 m2/MN, and 3.8 m2/yr, respectively. The average bearing capacity values at 2.5 m and 4.5 m depths were determined to be 186.39 kPa and 278.71 kPa, respectively. Settlement values were calculated empirically for immediate and consolidation settlement, with immediate settlement being high at 25.85 mm and consolidated settlement being 7.53mm. T50 and T90 values were also determined to be 1.32 and 4.52 years, respectively.
 Conclusion: It is recommended that a shallow foundation, down to the first layer, can be used for any light construction on the marginal land in Borikiri Sandfill, Port Harcourt, Nigeria. The values of k, Mv, and Cv also indicate that the soil is relatively compressible, which should be taken into account in any design or construction activities.