Standard Penetration Test Values Research Articles

Distribution of land stability based on standard penetration value (SPT) with various depth in Semarang city, Indonesia

Land stability is one of the main determining factors for the bearing capacity of the environment. The land stability is influenced by the condition and characteristics of the resources in the environment. The supply capacity in terms of the level of land stability for spatial use allocation has been based on the capacity of land for agriculture and the physical aspects of the land. It accordance with the local regulation i.e. no. 17 of 2009. Land stability includes the ability of land for agriculture and the physical aspects of land, as well as the stratigraphy of subsurface soil mass, especially geological characteristic. The research was conducted in Semarang City Indonesia by drilling and standard penetration test (SPT) and taking 448 undisturbed samples (UDS’s) of soil that scattered in the research area. Analysis of UDS’s have been carried out in the laboratory to obtain comparisons with SPT values in determining the level of land stability both vertically and horizontally. Soil types obtained are clay, silt, silt-sand, sand, and sand stone with a level of consistency and density in accordance with the measured SPT. Land stability values ranged from 0.201 kg/cm2-14.248 kg/cm2 covering all types of soil with different consistencies and density. The distribution of land stability is given in an infographic to get an overview of the land stability levels geographically at a depth of 2.5m, 5.0m, 7.5m, and 10.0m. This infographic can be useful for spatial evaluation, engineering guidance, and environmental research in Semarang City, Indonesia.

GIS based Vs30, Vsz & Dbed rock Mapping for the Shallow Sites of Islamabad, Pakistan

The location of Pakistan is in a collision zone among the Eurasian and Indian plate boundaries. The geological framework of the Northwest Himalaya makes Northern Pakistan susceptible to frequent moderate to major earthquakes. The devastating earthquake of October 8, 2005 caused 87,000 deaths, 2.8 million displacements and financial loss of 200 Billion USD equivalent to 6% GDP of Pakistan. Islamabad is in seismically active region, the studies conducted for this region addresses the poor soil conditions, non-engineering construction practices and high level of seismic shaking. However, none of these studies provided readily available ground maps (top 30m time average shear wave velocity V s30 , average soil shear wave velocity V sz & depth to bed rock D bed rock ) based on site specific geotechnical database. V s30 , V sz & D bed rock are important parameters for the evaluation of dynamic site characteristics of shallow bed rock sites. In Pakistan, Uniform Building Code (UBC-1997) is currently practiced, and the site classification are defined using site specific V s30 . In this study, geotechnical borehole database of 57 sites of Islamabad was collected to develop GIS based V s30 , V sz & D bed rock maps using Standard Penetration Test value (SPT-N). The borehole database includes, SPT-N, soil description and unit weight of soil for the Islamabad sites. In order to develop shear wave velocity (V s ) profiles, the available V s -SPT empirical correlations were evaluated where both SPT-N & V s measured data is available. The selected available correlations were applied to SPT-N database to develop representative Vs profiles. Using these V s profiles, V s30 , V sz & D bed rock GIS based maps were developed by applying Kriging interpolation in open source QGIS software. The proposed GIS maps can be used in preliminary earthquake design for seismic resilient earthquake design in Islamabad, Pakistan.

GIS based Vs30, Vsz & Dbed rock Mapping for the Shallow Sites of Islamabad, Pakistan

The location of Pakistan is in a collision zone among the Eurasian and Indian plate boundaries. The geological framework of the Northwest Himalaya makes Northern Pakistan susceptible to frequent moderate to major earthquakes. The devastating earthquake of October 8, 2005 caused 87,000 deaths, 2.8 million displacements and financial loss of 200 Billion USD equivalent to 6% GDP of Pakistan. Islamabad is in seismically active region, the studies conducted for this region addresses the poor soil conditions, non-engineering construction practices and high level of seismic shaking. However, none of these studies provided readily available ground maps (top 30m time average shear wave velocity V s30 , average soil shear wave velocity V sz & depth to bed rock D bed rock ) based on site specific geotechnical database. V s30 , V sz & D bed rock are important parameters for the evaluation of dynamic site characteristics of shallow bed rock sites. In Pakistan, Uniform Building Code (UBC-1997) is currently practiced, and the site classification are defined using site specific V s30 . In this study, geotechnical borehole database of 57 sites of Islamabad was collected to develop GIS based V s30 , V sz & D bed rock maps using Standard Penetration Test value (SPT-N). The borehole database includes, SPT-N, soil description and unit weight of soil for the Islamabad sites. In order to develop shear wave velocity (V s ) profiles, the available V s -SPT empirical correlations were evaluated where both SPT-N & V s measured data is available. The selected available correlations were applied to SPT-N database to develop representative Vs profiles. Using these V s profiles, V s30 , V sz & D bed rock GIS based maps were developed by applying Kriging interpolation in open source QGIS software. The proposed GIS maps can be used in preliminary earthquake design for seismic resilient earthquake design in Islamabad, Pakistan.

Evaluation of some soil characteristics from field SPT values using random number generation technique

Several engineering attributes, such as soil strength and deformability, are very significant and are regarded as the basis of any sort of foundation design. In determining the vibration extent depending on the used soil numerical models, soil characteristics represented by the shear wave velocity, cohesion, angle of internal friction and Poisson’s ratio are crucial. Different kinds of parameters are identified in various used manuals in numerical modelling. The outputs of these numerical programs are commonly dependent on the input parameters. Thus, in the analysis of any geotechnical problem, the correct selection of rigorous values of the engineering properties of the soil is extremely serious. In this study, a set of field data for Standard Penetration Test (SPT) values has been collected from more than twenty different places in Kirkuk city. In addition, using the random number generation method, several empirical relationships of various soil properties have been advanced in terms of the spectrum of the collected SPT values. The functional benefit of the relationships developed can be used to validate the observed experimental geotechnical data integrated in the architecture of the different civil engineering ventures. As a result, for the SPT-N values ranged from 4 to 44, the predicted soil cohesion and angle of internal of friction increased from 17 kPa to 281 kPa and 4° to 38° respectively. As an overall evaluation, the shear wave velocity ranged from 72 (m/s) to 367 (m/s) whereas the field and predicted UCS varied from 60 kPa to 320 kPa and 54 kPa to 400 kPa respectively.

Evolution of Deep Neural Network Architecture Using Particle Swarm Optimization to Improve the Performance in Determining the Friction Angle of Soil

This study focuses on the use of deep neural network (DNN) to predict the soil friction angle, one of the crucial parameters in geotechnical design. Besides, particle swarm optimization (PSO) algorithm was used to improve the performance of DNN by selecting the best structural DNN parameters, namely, the optimal numbers of hidden layers and neurons in each hidden layer. For this aim, a database containing 245 laboratory tests collected from a project in Ho Chi Minh city, Vietnam, was used for the development of the proposed hybrid PSO-DNN model, including seven input factors (soil state, standard penetration test value, unit weight of soil, void ratio, thickness of soil layer, top elevation of soil layer, and bottom elevation of soil layer) and the friction angle was considered as the target. The data set was divided into three parts, namely, the training, validation, and testing sets for the construction, validation, and testing phases of the model. Various quality assessment criteria, namely, the coefficient of determination (R2), mean absolute error (MAE), and root mean square error (RMSE), were used to estimate the performance of PSO-DNN models. The PSO algorithm showed a remarkable ability to find out an optimal DNN architecture for the prediction process. The results showed that the PSO-DNN model using 10 hidden layers outperformed the DNN model, in which the average correlation improvement increased R2 by 1.83%, MAE by 5.94%, and RMSE by 8.58%. Besides, a global sensitivity analysis technique was used to detect the most important inputs, and it showed that, among the seven input variables, the elevation of top and bottom of soil played an important role in predicting the friction angle of soil.

Prediction of standard penetration test value on cohesive soil using artificial neural networks

Soil investigation is the main key in starting construction. Standard Penetration Test (SPT) and Cone Penetration Test (CPT) are field tests often used to estimate soil parameters for foundation design purposes. The SPT value (N-SPT) shows a correlation between the CPT value and other soil parameters. At present, there have been many conventional correlations examining these correlations, but the nonlinear nature of the soil due to very complex soil formations means that this correlation cannot be used in all situations. This research aimed to predict the value of SPT on cohesive soil based on CPT test data and soil physical properties using artificial neural network capabilities using the Backpropagation algorithm, and the activation function was bipolar sigmoid. This study used 284 data from several places in Sumatra Island, Indonesia, with data input were tip resistance, shaft resistance, effective overburden pressure, percentage of liquid limit, plastic limit, sand, silt, and clay. The results showed that the training data of RMSE was 3.441, MAE and R2 were 0.9451 and 2.318, respectively while test data showed RMSE, MAE, R2 were 2.785, 2.085, and 0.9792, respectively. It means that the proposed artificial neural network NN_Nspt(C) was promising to predict the N-SPT value with a minimum error value and a strong regression equation.

Engineering geology and geotechnical characterization of Tabriz Metro Line 2, Iran

The present study was performed in order to determine the engineering geology and geotechnical details of soils and rocks along Tabriz Metro Line 2(TML2) by using the information and raw data which were acquired by borehole drilling and all field and laboratory tests in the study area. The minimum and maximum depths of the boreholes were 15 and 40 m, respectively. The results of their analysis revealed that geologically, the areas of metro route, mainly formed by alternating layers of claystone, siltstone, marl, and conglomerate, covered mainly by the alluvial deposits and in addition to older, dextral, strike-slip North Tabriz Fault (NTF) which is a major and most important geological structure of Tabriz area, there are also many minor and generally young and seismically active faults. The results of investigation on the groundwater depth in boreholes of TML2 also indicated that the groundwater depth varies between 1.5 and 30 m, along the route of metro. Eventually, based on the standard penetration test values (N-SPT), it was revealed that soils of the western parts of TML2 are in the group of dense to very dense, the central parts are in the group of very dense (Bazaar area) and dense (Fahmideh area), and the eastern parts are very dense. And finally the results achieved from determining groundwater sulfate values according to Concrete Code of Iran (CCI) indicated that the amount of soluble sulfate in the soil is mild to extremely high. Accordingly, the amount of sulfate increases from the western to the eastern parts. So that, this value is between 200 and 26,500 ppm. Based on these studies, the average of sulfate in the western, central and eastern parts is, respectively, 1118, 1275 and 4840 ppm. Thus, the groundwater in the east part is highly aggressive, and deterioration of concrete lining of the tunnel is expected in the near future.

Soft soils: A study on their electrical resistivity values and geotechnical properties (porosity, SPT and particle size distribution)

Soft soils pose abundant engineering issues due to its low bearing capacity and shear strength. Comprehensive study on soft soil’s physical properties such as shear strength and ability to store water (porosity) could help in devising the optimum ground improvements and foundations techniques. Therefore, physical properties of soft marine clay in Nibong Tebal were thoroughly studied using 2-Dimensional Resistivity Imaging (2-DRI) method in conjunction with porosity measurements, standard penetration test values (SPT-n) and particle size distribution (PSD) analysis. The 2-DRI profile depicts three lithologies, which are unsaturated topsoil, saturated soft clayey soil and saturated sandy soil in the area. The soft soil extends up to 32 m in thickness where it overlies the sandy layer and could be correlated back to lithology profile from borehole record. Additionally, soil samples were collected at three locations along the survey line for porosity measurements via saturation porosimetry method. The samples demonstrate that the clay layer has a very large porosity range and signifies that the soil will compress tremendously under load. On the other hand, SPT-N values of the soft clay is also very low; thus, could be classed as very soft to soft cohesive soil with very low shear strength as compared to a higher range SPT-n values of the sandy layer. The PSD result also compliments the 2-DRI, porosity and SPT results to show distinct differences between topsoil and the soft clay layer in terms of the presence of fine grains. These results further indicate that the thick upper layer is not capable of bearing immense loads such as high-rise infrastructures due to the soil’s high porosity and low shear strength. Hence, the area must undergo ground remediations prior to any infrastructure developments on the land.

Application of geophysical methods to evaluate soil dynamic properties in Penang Island, Malaysia

Abstract The essential criterion of selecting the site for building foundations is the underlying soil. This vital requirement stems from the associated potential for disaster should the ground condition be unstable. Conventionally, the method of geotechnical drilling is used in soil investigation work. However, this method is limited to providing subsurface information only at one particular point. This research aims to utilise geophysical methods to investigate the soil dynamic properties of various lithology types via application of electrical resistivity method (ERM), seismic refraction (SR), and multichannel analysis of surface wave (MASW) methods. The soil dynamic properties (bulk density, Poisson’s ratio, Young’s modulus, shear modulus, bulk modulus) and material bearing capacity (subgrade reaction coefficient, ultimate and allowable bearing capacity) were computed using a relative formula by using compressional wave (VP) and shear wave velocities (VS). The calculated values of soil dynamic properties and material bearing capacity for the three study areas are capable in determining the competency and stiffness of subsurface layers for building foundation. The results leading to this conclusion can be verified by the values of standard penetration test value (SPT-N) from borehole record. From this study, it is apparent that the soil dynamic properties and material bearing capacity values are essential to determine the competency of soil, in turn aiding in determining the area suitable for the shallow foundation to rest. Thus, geophysical methods are time- and cost-saving, as well as non-intrusive, recommended for site investigation before starting any construction work.

Different Soft Soil Improvement Techniques of Dhaka Mass Rapid Transit Project

The objective of this research is to the analysis of the different soil improvement techniques and the comparable model of these soil improvement techniques. In Bangladesh, different soil improvement techniques were used by different construction firms to improve the soil bearing capacity, but many of them could not verify the techniques after improvement. The verification of the soil improvement techniques is more important than the implementation of the soil improvement techniques. A comparison has been made between results obtained from three soft soil improvement techniques. Analysis of the effectiveness of soft soil improvement technique before and after improvement technique. From analyses, it has been revealed that for Tongi to Uttara along the Project package CP01 soft clay layer is effective for Sand Compaction Pile (SCP) and the sand layer, which is susceptible to liquefaction is effective for Dynamic Compaction (DC) method. After the improvement standard penetration test (SPT) value increases dramatically; this is a significant finding of this research.
 Journal of Engineering Science 11(2), 2020, 37-44

Field test on pile tip resistance of closed-end jacked pipe pile penetrating into layered foundation

In the layered soil foundation mainly composed of silty clay and silty clay, test piles with full cross-section pressure sensors installed at the end of piles are used to continuously and intensively collect pile tip resistances in the whole penetrating process with high density. throughout the entire process. According to the pile tip resistance curves of multiple penetration strokes, the change stage of the initial penetration of the pile tip resistance into the soil layer and the change stage of continuous penetration into the same soil layer are defined, which are divided into linear steep increase segments, nonlinear ramp segments, and platform segments, nonlinear slow-down section, linear steep drop section. When the pile end continuously penetrates through the interface of multiple soil layers, the change stage of the pile end resistance lacks a linear steep increase section compared with the initial penetration soil layer. The initial value of the steep drop of the previous stroke is close to the final value of the steep rise of the latter stroke, which can reflect the limit of the elastic compression of the soil, and is calculated by the average value of Qc, and is used as the pile foundation design. The pile tip resistance curve during the pile sinking process is similar to the static penetrating Qc curve. The maximum tip resistance of every layer in the layered soil is linear with the Qc value of the static penetrating probe and the average number of standard penetrations. Analysis of this situation found that the residual end-resistance after restoration was linearly related to the Qc value of cone penetration test(CPT) and the N value of standard penetration test(SPT). The fitting formula of elastic limit pile end resistance and ultimate pile tip resistance and residual tip resistance are put forward; and the fitting formula of ultimate pile tip resistance is more accurate than that of empirical parameter method, static cone penetration method and limit equilibrium theory.

Evaluation of the road failure using resistivity and screw driving sounding testing techniques: A case study in Ang Thong province, Thailand

This paper presents the case study of a failure of road along an irrigation canal in Ang Thong province, Thailand. The canal side road failure is a recurring problem that occurs annually due to the drought. The concept of resistivity survey related to the soil moisture; therefore, the results can be used to evaluate and confirm the potential of road failure in the weakness zones. Moreover, the screw driving sounding test is a new field testing to investigate the soil classification, estimate shear strength parameters, and estimate equivalent Standard Penetration Test (SPT) value. The study aimed to evaluate a canal side road failure, which was achieved by combining the resistivity survey and screw driving sounding test. The effectiveness of the combining site investigation was confirmed by using the 2-dimensional (2-D) finite element software. A comparison of the stability of the canal side road in the failure zone and stability zone was performed by calculating the factor of safety under low and high -water level conditions. Consequently, it was confirmed that the combination of resistivity survey and screw driving sounding test can be applied for site investigation to evaluate the stability of canal side road.

Study of Pushover Analysis on RC Framed Structure with Underground Structure Considering the Effects of Soil Structure Interaction

This study states that the effects of soil structure interaction on the Reinforced Concrete (RC) framed structures is directly influenced by the soil properties of the site. Here, one preexisting structure is taken for the study. The building is a hospital building with two underground basements. Taking into account the actual soil condition of building site, this study provides idea on the soil structure interaction on the structure The properties of springs are calculated from different standard penetration test (SPT) values, Poisson’s ratio and elasticity of soil along the depth of the soil. Entire soil-foundation-structure system is modelled and analyzed using spring approach. Static analysis, response spectrum analysis and pushover analysis (PA) are done in order to find the variations in natural periods, base shears and deflections of the structures by incorporating soil flexibility as compared to structures with conventional fixed base. Pushover analysis is done to evaluate the performance of the structure when modelled in fixed base and spring base system.

Prediction of Pile Axial Bearing Capacity Using Artificial Neural Network and Random Forest

Axial bearing capacity of piles is the most important parameter in pile foundation design. In this paper, artificial neural network (ANN) and random forest (RF) algorithms were utilized to predict the ultimate axial bearing capacity of driven piles. An unprecedented database containing 2314 driven pile static load test reports were gathered, including the pile diameter, length of pile segments, natural ground elevation, pile top elevation, guide pile segment stop driving elevation, pile tip elevation, average standard penetration test (SPT) value along the embedded length of pile, and average SPT blow counts at the tip of pile as input variables, whereas the ultimate load on pile top was considered as output variable. The dataset was divided into the training (70%) and testing (30%) parts for the construction and validation phases, respectively. Various error criteria, namely mean absolute error (MAE), root mean squared error (RMSE), and the coefficient of determination (R2) were used to evaluate the performance of RF and ANN algorithms. In addition, the predicted results of pile load tests were compared with five empirical equations derived from the literature and with classical multi-variable regression. The results showed that RF outperformed ANN and other methods. Sensitivity analysis was conducted to reveal that the average SPT value and pile tip elevation were the most important factors in predicting the axial bearing capacity of piles.

Vibro-compaction at a land reclamation site in Phuket, Thailand

Phuket is the biggest island province in Thailand. Located in the southern part of the country, this island is famous and a favourite destination for foreign and Thai tourists alike. Consequently, this province continually develops with booming tourism and hence there is a need for large and advanced infrastructure. Construction projects are increasing each year, but the available land area is limited and land reclamation has therefore become an alternative. Sand backfill material is available on the island. However, the loose sand fill needs to be densified for structural support or structural foundations, and the ground improvement technique called vibroflotation is suitable for improving the sand density in a small area over a short period. This paper presents an assessment of the effectiveness of vibroflotation in the densification of sand fill, which was applied for the first time in Thailand. The standard penetration test values of the sand fill before and after improvement were compared, evaluated and confirmed with regard to liquefaction susceptibility during earthquake occurrences. It was confirmed that the vibroflotation technique can increase the density of sand fill in land reclamation and can increase its bearing capacity as well as prevent liquefaction during earthquakes.

Assessment on liquefaction potential of seabed soil in Chang-Bin Offshore wind farm considering parametric uncertainty of standard penetration tests

Liquefaction potential analysis is a required task in the foundation design process of offshore wind turbine in Taiwan. The standard penetration test (SPT) is mostly used in the preliminary soil investigation of the pilot offshore wind farm in Chang-Bin, Taiwan. Due to the different experimental conditions and operating conditions, the N value (SPT-N) of SPT varies greatly. This study applies statistical methods in conjunction with the New Japan Road Association simplified-empirical method (NJRA method) to incorporate the uncertainty of SPT-N values into the offshore liquefaction potential assessment to quantify the risk of seabed liquefaction. The study statistics the field experimental geotechnical parameters SPT-N and determines the probability density function of the SPT-N distribution of each layer of soil in the offshore wind farm. In order to quantify the risk of seabed soil liquefaction potential, the Monte Carlo random sampling method is used, and by the NJRA method to carry out the seabed liquefaction potential in Changhua, Taiwan. After comparing, the results obtained by the current SPT-based soil liquefaction potential assessment by deterministic approach are conservative. In the ground investigation of offshore wind farm development, the method proposed in this paper can access the thickness of liquefiable soil layers under any given probability for optimizing offshore wind turbine foundation design.

Soft computing approach for prediction of surface settlement induced by earth pressure balance shield tunneling

Estimating surface settlement induced by excavation construction is an indispensable task in tunneling, particularly for earth pressure balance (EPB) shield machines. In this study, predictive models for assessing surface settlement caused by EPB tunneling were established based on extreme gradient boosting (XGBoost), artificial neural network, support vector machine, and multivariate adaptive regression spline. Datasets from three tunnel construction projects in Singapore were used, with main input parameters of cover depth, advance rate, earth pressure, mean standard penetration test (SPT) value above crown level, mean tunnel SPT value, mean moisture content, mean soil elastic modulus, and grout pressure. The performances of these soft computing models were evaluated by comparing predicted deformation with measured values. Results demonstrate the acceptable accuracy of the model in predicting ground settlement, while XGBoost demonstrates a slightly higher accuracy. In addition, the ensemble method of XGBoost is more computationally efficient and can be used as a reliable alternative in solving multivariate nonlinear geo-engineering problems.

Geotechnical Features of Basrah City, Iraq

Basrah is considered as the economic capital of Iraq. In recent years, it showed a rapid growth in population and, accordingly, an increasing investment in construction industries. This paper presents information about the geotechnical characteristics of Basrah soil. For this purpose, geotechnical data have been collected covering wide areas of the city. The study area was divided into two zones, one of them was further divided into three subzones. For each of the zones considered, geotechnical information including typical soil profiles, Standard Penetration Test (SPT-N) values, Atterberg limits, sieve analysis results, consolidation test results and other physical aspects were given. Furthermore, chemical analysis of Basrah soil was also presented. According to field and laboratory results, soils in this region can be classified into two distinct zones. The eastern zone, which mainly forms of soft and medium cohesion soils extended from the soil surface down to a depth of (16 – 26) m, and, the western zone, which can be identified by the sandy surficial and stratigraphic soil.

A Mathematical Model for Prediction the Embedment Depth of the Contiguous Piles Used in the Interchange of Zakho Entrance

Determination of the depths of the embedment of contiguous piles requires extensive soil investigation to obtain the soil physical parameters. In addition, a large number of such piles involved in restricted access projects make that depth an essential problem. A simple mathematical model for predicting the depth of embedment using the height of the retained soil, the standard penetration test values, and the bulk unit weight of the soils encountered for 261 pile data sets was introduced using an artificial neural network approach. The coefficient of determination equals to 0.99 for the tested the data reveal that the depth of embedment was accurate against those achieved in Zakho interchange. The importance and parametric studies obtained show that the major parameter which affects the depth of embedment was the height of the retained soil whereas the effect of other parameters is relatively less.

Determination of relationship between standard penetration test and geotechnical parameters in Ahwaz soil

ABSTRACT The present study is the result of more than 150 geotechnical investigations that were conducted over 2 years (from 2015 to 2016) on the Ahwaz soil (which is mainly composed of clay with low plasticity in different regions). The standard penetration test was performed at all the boring locations, and after preparing the undisturbed Shelby tube samples from different depths, the unconsolidated undrained triaxial (UU), Atterberg limits, in situ moisture content and grading tests were performed on all samples. All of the abovementioned parameters are presented for the Ahvaz soil, and the range of values of each of the parameters were investigated, and finally, the relationship between the modulus of elasticity and the standard penetration test was studied. The effect of different soil parameters and their contribution to the determination of soil elasticity modulus is another important result of this study. The most important result of this study could be the different classifications of soil elasticity moduli by using the sample Nspt values to estimate the elasticity moduli because the standard penetration test value has the highest correlation and the most significant relationship with elasticity moduli.