Standard Penetration Test Data Research Articles

A Machine Learning-Based Approach for Predicting Installation Torque of Helical Piles from SPT Data

Helical piles are advantageous alternatives in constructions subjected to high tractions in their foundations, like transmission towers. Installation torque is a key parameter to define installation equipment and the final depth of the helical pile. This work applies machine learning (ML) techniques to predict helical pile installation torque based on information from 707 installation reports, including Standard Penetration Test (SPT) data. It uses this information to build three datasets to train and test eight machine-learning techniques. Decision tree (DT) was the worst technique for comparing performances, and cubist (CUB) was the best. Pile length was the most important variable, while soil type had little relevance for predictions. Predictions become more accurate for torque values greater than 8 kNm. Results show that CUB predictions are within 0.71,1.59 times the real value with a 95% confidence. Thus, CUB successfully predicted the pile length using SPT data in a case study. One can conclude that the proposed methodology has the potential to aid in the helical pile design and the equipment specification for installation.

3D Full-Waveform Tomography of Standard Penetration Test-Seismic Wavefields in Karst Florida Limestone

The shallow subsurface across large parts of Florida consists of weathered karst limestone, a spatially variable porous stratigraphy with significant influence in the design and load capacity of deep foundations. For reliable load transfer of the super structure into the bearing soil/rock, detection of voids and weak zones is crucial. This study investigated the capabilities of a recently developed standard penetration test (SPT)-seismic testing method for characterizing a large volume of soil/rock properties with a single SPT. The method utilizes a three-dimensional full-waveform inversion (3D FWI) of wavefields induced by SPT blows at depths (in-depth source) to characterize the subsurface around the SPT borehole. A site in Florida that presents shallow, surface karst limestone, was the location of a field experiment that consisted of two 36- × 18-m areas, each with an SPT at the area center. Seismic wavefields induced by SPT blows at depth were recorded by 72 vertical geophones on the ground surface and analyzed by the 3D FWI. The results revealed that subsurface soil/rock properties were characterized in submeter pixels over a large 3D domain of 24 × 36 × 18 m (depth × length × width). Multiple voids at various depths from 5 to 17 m were successfully detected at the site and confirmed by SPT data. The results suggested that the SPT-seismic method is an efficient tool for site investigation, as a bridge pier or pile group could be designed with only one SPT.

Analysis Of Bearing Capacity Of Pile Foundations Using Analytical Method And Finite Element Method

The foundation is the lower part of a structure used as a load distributor for loads generated. The selection of foundation types in building construction must consider the type and characteristics of the soil at the construction site to avoid construction failures. This analysis is conducted to determine the bearing capacity of pile foundations using analytical and finite element methods. The type of foundation used in this analysis is a pile foundation with a pile length of 8 meters and a pile diameter of 0.4 meters. For the analytical calculation, Standard Penetration Test (SPT) data obtained from PT. Adhi Karya (Persero) for the Infrastructure Green House Biodiversity LIPI Cibinong-Bogor project are used, employing the analytical method (Alpha Method) and the finite element method with the assistance of Plaxis 2D V.8 software. The results of the analysis show that the bearing capacity of the group pile foundation (Qg) for a pile diameter of 0.4 meters and a pile length of 8 meters on clayey soil, based on SPT data using the analytical method (Alpha Method), is 60.432 tons. Meanwhile, the bearing capacity of the horizontal pile foundation using the Broms method is 6.03 tons. The bearing capacity obtained using the Finite Element Method yields an ultimate load on the group pile (Qq) of 57.89 tons. The bearing capacity of the group pile foundation (Qg) from both sets of data, with a difference of 2.5%, meets the requirement, being greater than the axial load (P) of 42.6 tons that must be supported.

Liquefaction potential analysis based on standard penetration test data at irrigation canals in Sibowi Area-Central Sulawesi Province

A phenomenon in which non-cohesive soil in saturated conditions loses its carrying capacity owing to the reduced stiffness and strength of the soil during earthquake shaking or rapid loading is called liquefaction. This occurs under the structure and can cause damage during earthquakes. In this study, we estimated the possibility of liquefaction in the main irrigation canals in the Sibowi area of Central Sulawesi Province, considering that the soil type in this area is sandy. Liquefaction analysis uses a simplified procedure using Standard Penetration Test data to obtain the Safety Factor and estimate the potential level of liquefaction using the Liquid Potential Index (LPI) method. According to the analysis, with the 7.5 Mw earthquake and groundwater levels observed, most of the soil layer below the irrigation canals still has liquefaction potential at 15 m to 19.5 m. The LPI result that 5 (five) out of 10 (ten) boreholes have the potential for liquefaction in low to moderate categories, and the boreholes that have liquefaction potential have groundwater depths between 14 and 16 m.

Assessment of liquefaction potential and damage on the toll road construction in earthquake-prone area, Sleman Regency, Yogyakarta

The construction of toll roads in earthquake-prone areas presents significant challenges due to the potential occurrence of liquefaction, a seismic phenomenon in fine-grained soils losing strength during earthquakes. The research was conducted at a toll road construction site in Sleman Regency, Yogyakarta, an area near the active Opak fault which increases its vulnerability to liquefaction. The objective of this study is to analyse the liquefaction potential and damage on the surface in research area. The method used is simplified procedure by Idriss and Boulanger which assessing the cyclic stress ratio and cyclic resistance ratio based on standard penetration test and laboratory data. Then, Liquefaction Potential Index (LPI) and Liquefaction Severity Index (LSI) are calculated. Finally, vertical displacement caused by liquefied soil is estimated using the post-cyclic reconsolidation model to understand its impact on the surface. The study shows low to very high liquefaction potential at the toll road construction site in Sleman Regency. With a vertical displacement of 4.69 cm to 38.83 cm, surface damage can range from low to extensive, emphasizing the need for liquefaction mitigation in earthquake-prone areas like Yogyakarta during toll road infrastructure planning.

Probabilistic Evaluation of Earthquake-Induced Liquefaction Using Bayesian Network Based on A Side-by-Side SPT-CPT Database

In situ tests such as standard penetration test (SPT) and cone penetration test (CPT) are often conducted to evaluate the probability of earthquake-induced liquefaction. However, the models adopted have seldom attempted to utilize SPT and CPT data simultaneously. In this study, a side-by-side SPT-CPT database at historical earthquake sites is established; then, a Bayesian network model is constructed to predict the probability of soil liquefaction based on this database, with which the SPT and CPT data are utilized simultaneously. Next, comparative studies are undertaken to illustrate the superiority of the Bayesian network-based probabilistic soil liquefaction model developed over other models, in terms of six SPT- and CPT-based conventional liquefaction models in the literature and two Bayesian network-based models. It should be noted that the liquefaction sites with two in situ tests are scarce and side-by-side SPT-CPT data can be incomplete, which leads to challenges in applying the Bayesian network model developed. To address this problem, correlations between SPT and CPT data are analyzed, and these correlations are further included in the Bayesian network model; as a result, a modified Bayesian network model is reached. Finally, the influence of the proportion of missing data in the incomplete SPT-CPT data on the liquefaction prediction accuracy is discussed.

Perbandingan Daya Dukung Tiang Pancang dengan Alat Berat Drop Hammer dan Hydraulic Static Pile Driver (HSPD)

The foundation is a base or bottom structure that can carry all the loads above it. Foundation bearing capacity and foundation settlement are very important for foundation planning. In the construction project for the Faculty of Agricultural Technology building at Jember Polytechnic, a recalculation analysis was carried out to compare the carrying capacity using two methods, namely HSPD and Drop Hammer. Soil bearing capacity is calculated based on Standard Penetration Test (SPT) data from 2 soil investigation points. Next, the soil bearing capacity is calculated using the Drop Hammer assumption. The research results show that there is a difference in the carrying capacity of HSPD and Drop Hammer. And the results can be carried out using 2 HSPD heavy equipment and a Drop Hammer at that location. In comparison, Drop Hammer and HSPD driving on a 25 x 25cm mini pile foundation can be carried out. And in the field you can use 2 heavy equipment simultaneously, namely HSPD for spun pile D 50 cm at the smallest permitted carrying capacity value of 68 tonnes at a depth of approximately 12 meters and drop hammer for mini piles at a permitted carrying capacity value of 40.94 tonnes at a depth of approximately 6 meters. However, if you use a drop hammer in areas near residents, don't forget to plan the trench work to reduce vibrations to the surrounding area.

Improved computational methods for probabilistic liquefaction hazard analysis

Current procedures for analysis of and design against liquefaction hazards focus primarily on the use of probabilistic ground motions at a single ground-shaking hazard level, with the cyclic loading represented by a peak ground acceleration (PGA) corresponding to a target return period and a single representative moment magnitude Mw. These parameters are typically used in conjunction with deterministic simplified procedures for estimating liquefaction triggering and consequences that largely neglect the considerable uncertainties inherent to liquefaction problems. Motivated by these limitations and the resulting inconsistencies in liquefaction design levels, early methods for probabilistic liquefaction hazard analysis (PLHA) were proposed that incorporate the full ground motion hazard space, integrated with probabilistic liquefaction triggering models. Such methods provide liquefaction factor of safety (FSL) hazard curves for standard penetration test (SPT) data. Recognizing the increased use of higher-resolution cone penetrometer test (CPT) data in engineering analysis and design and the potential computational challenges it presents, an expanded suite of probabilistic triggering models, and wider availability of more detailed seismic hazard data, an improved PLHA computational methodology is presented in this study. The methods described utilize the U.S. Geological Survey National Seismic Hazard Model directly through web services to obtain PGA hazard and disaggregation calculations for any site and average shear wave velocity in the upper 30 m of the site (Vs30) in the conterminous United States, to reconstruct the PGA hazard space for use in PLHA calculations, and to employ array calculations for efficient liquefaction hazard curve estimates for the thousands of CPT measurements in a given profile. The framework presented here is modular in nature, and discussion on the use of alternative models and extension to probabilistic liquefaction consequence evaluation is presented. The importance of appropriate representation of probabilistic liquefaction model uncertainties is also highlighted, along with the impacts of different levels of uncertainty on the PLHA calculation. Finally, a potential roadmap for incorporation of the PLHA framework in seismic provisions is presented, with an illustration of how it can address current limitations and impacts in liquefaction hazard analysis and design.

Knowledge-based multiple point statistics for soil stratigraphy simulation

An accurate representation of subsurface stratigraphy in the form of geotechnical profiles is a prerequisite for optimal underground design and safe construction. This paper proposes a novel knowledge-based multiple point statistics (KMPS) method to simulate the heterogeneities and spatial trends of subsurface strata and to generate geotechnical profiles. This approach incorporates domain knowledge in the form of cone penetration test and standard penetration test data as well as results from laboratory testing to increase simulation accuracy. A novel varying search template size and similarity threshold is adopted to alleviate the computational cost of the simulations. Ablation analyses are used to quantify the improvement of the proposed KMPS algorithm over existing baseline multiple point statistics algorithms. By way of example, the proposed approach is applied to real-world exploration data from the Suzhou No.6 metroline project. The results show that the computational cost of KMPS is effectively minimized whilst the simulation accuracy can be improved by up to 13.3%. The algorithm is further validated by extending the simulation to a test image. With sparse exploration data, the KMPS method is shown to effectively and efficiently predict soil profiles based on prior experience embodied by a training image, thus enabling a reduction in the number of field exploration boreholes.

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.

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.

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.

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.

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.

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.

Analisis Struktur Dinding Penahan Tanah Proyek Rehabilitasi Jembatan Rangka Baja Pantai Dona Kabupaten Aceh Tenggara

Retaining wall is a type of turf that is used to prevent soil from collapsing. Standard Penetration Test (SPT) data can be used to calculate the limit bearing capacity. The purpose of this research is to calculate the limit bearing capacity, to analyze retaining walls and soil stability and to calculate the depth of the pile foundation of retaining walls. This type of research method is quantitative and qualitative research. The research results were obtained based on the soil structure profile of the SPT test results for foundation depth, in which the relative density level of the sand layer can be known, namely N: 0–4 very loose. N :4–10 Release. N : 10–30 Moderate. N : 30–50 Solid. N :>50 Very Dense. And the relative density level of the clay layer can be known, namely N : 0–2 Very Soft. N : 2–4 Soft. N : 4–8 Moderate. N : 8–15 Hard/Stiff. M : 15–30 Very Loud. N : >30 Dense: sedimentary soil type consisting of rocky sandy loam (0.00 – 4.80 m). The carrying capacity using the targazhi method is 29.14 tons. Using the Mayerhof method of 184.45 tonnes. For the soil type of this steel bridge project, the penetration depth of the soil foundation is 6.50m.

Maximum shear modulus estimative from SPT for some Brazilian tropical soils

Maximum shear modulus (G0) has been used in various geotechnical jobs (e.g., seismic site assessment, machine vibration and pile driven). Laboratory and in situ determination of G0 is not a current practice in Brazil. G0 can be estimated from empirical correlations based on in situ tests like Standard Penetration Test (SPT) and Cone Penetration Test (CPT) in the preliminary design phase. Several empirical correlations to estimate G0 from SPT N value have been developed and are available in the literature. However, most of these correlations were established based on experience with well-behaved soils formed in temperate and glacial zones, which may not always be used for tropical soils. This paper assessed and discussed the applicability of some correlations for G0 estimative from SPT data in lateritic and saprolitic soils. The classical correlations for sedimentary soils underestimated G0 of tropical soils. After updating the database, the tropical soils correlations reasonably estimated G0 for the lateritic ones, which was not the case for the saprolitic soils. It was observed that differentiating the soils only as lateritic or saprolitic was not adequate for a good G0 estimate for the saprolitic sandy soils. It was found that only the lateritic soils correlation can be used with caution as a preliminary attempt to estimate G0 from SPT N value in soils with similar characteristics to the ones presented in this paper.

A new approach to the correlation of SPT-CPT depending on the soil behavior type index

In this study, a model based on soil behavior type index (Ic) has been proposed for the conversion of field cone penetration test (CPT) data to the standard penetration test (SPT) blow counts (N). The field data used in the study were obtained from the fluvial soils formed by the Sakarya river in Adapazarı (Turkey). According to the proposed model, it is understood that there are exponential relationships between SPT-N and CPT data with varying coefficients (constant multipliers and exponents) for different Ic intervals. While the coefficients of the equations were kept constant in the previous formulations developed based on Ic, the current study revealed that the mentioned coefficients should be changed for different Ic intervals. The normalized cone resistance (qt/ Pa) or corrected SPT-N values (N60), found with the model created with the final coefficients, were evaluated. The results obtained by using the new model proposed in this paper were compared with other models generally accepted in the literature. It has been revealed that the results achieved by this new model are the closest ones to the measured values compared to the other methods. To verify the proposed model, CPT-SPT data pairs that were not used in the model generation were analyzed. Verification analyses confirmed that the developed method has given more realistic results than the other methods suggested in the literature. It was understood that the error rate in the model, in which conversion between CPT and SPT data can be made by considering the variability in the soil behavior type index, is lower than the others. As a result, the paper gives a new perspective by introducing a simple and newly updated form of estimating N60 values.