scholarly journals Cramming the Specificities in Contemplating Safe Bearing Capacity for the Foundation Assessed from Borehole Samples in a Sandy-Moorum Zone

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Tarun Kumar Lohani ◽  
Melkamu Teshome Ayana ◽  
Abdella Kemal Mohammed ◽  
Jyotiranjan Pattanaik

Borehole samples drilled up to a depth of 10 m provide a clear understanding whether a foundation is safe for any structure. The main objective of the present study reconnoitered the soil bearing capacity and foundation settlement characteristics using the standard penetration test (SPT) data obtained from 3 boreholes at 1 m, 2 m, and 3 m depths to correlate soil properties and deterrents, if any, created by groundwater. The methodology of the research is to collect soil samples, and ensuing subsoil analysis was performed in order to obtain concrete information to optimize the foundation system within the safe bearing capacity of soil and its allowable settlement. The scope of the work encompasses conducting detailed soil investigation from drilling logs, laboratory testing, and conducting and estimating safe bearing capacity. The result of the research aims at providing safety to the foundation from the investigations of conclusive recommendation to be adopted which would be economically feasible and structurally secured.

UKaRsT ◽  
2020 ◽  
Vol 4 (1) ◽  
pp. 109
Author(s):  
I Wayan Ariyana Basoka

Design of building structure always related to the foundation, field testing is often done to test the bearing capacity of the soil in the form of a cone penetration test (CPT) and a standard penetration test (SPT). From the two field tests that are often done, it is necessary to research the amount of bearing capacity obtained through CPT and SPT data. This study uses a bearing capacity analysis of the pile foundation using CPT and SPT data in Pesanggaran, Bali, Indonesia. The analysis was carried out by comparing the bearing capacity of pile foundations using pile foundations with dimensions of 15 cm, 20 cm, 25 cm and 30 cm at a level of 10 meters. The results of the bearing capacity percentage are then compared. From the analysis conducted, the bearing capacity of pile foundations using CPT data has a higher value than the carrying capacity of poles using SPT data with a bearing capacity difference of 10,4-16,3%.Perancangan suatu struktur erat kaitannya dengan fondasi, pengujian lapangan yang sering dilakukan untuk mengetahui daya dukung fondasi berupa cone penetration test (CPT) dan standard penetration test (SPT). Dari dua pengujian lapangan yang sering dilakukan, maka perlu dilakukan dilakukan penelitian mengenai seberapa besar perbedaan hasil daya dukung yang diperoleh melalui data CPT dan SPT. Penelitian ini melakukan perbandingan analisis daya dukung fondasi tiang dengan menggunakan data CPT dan SPT di Pesanggaran, Bali, Indonesia. Analisis dilakukan dengan membandingkan daya dukung fondasi tiang menggunakan fondasi tiang berdimensi 15 cm, 20 cm, 25 cm, dan 30 cm pada kedalaman 10 meter. Hasil persentase daya dukung yang diperoleh kemudian dibandingkan. Dari analisis yang dilakukan, diperoleh daya dukung fondasi tiang menggunakan data CPT memiliki nilai lebih tinggi daripada daya dukung tiang menggunakan data SPT dengan perbedaan daya dukung 10,4-16,3%.


2012 ◽  
Vol 49 (4) ◽  
pp. 394-402 ◽  
Author(s):  
Lianyang Zhang ◽  
Jin-Jian Chen

In this paper, the effect of spatial correlation of standard penetration test (SPT) data on the bearing capacity of driven piles in sand is analyzed. First, the direct approach for using SPT data to determine the bearing capacity of piles in sand is used to derive the expressions for probabilistic prediction of pile bearing capacity by considering the spatial correlation of the SPT data. To analyze the relationship between the probability of failure and the factor of safety, a procedure based on the advanced first-order, second-moment (FOSM) method is used. Then parametric studies are conducted on the spatial correlation between the spatial average of SPT numbers over the pile length, NLV, and the spatial average of SPT numbers over an interval near the pile base, NbV, and its effect on the bearing capacity of piles. The results indicate that it is important to consider the spatial correlation between NLVand NbVin the probabilistic prediction of pile bearing capacity. Ignoring this spatial correlation will underestimate the probability of failure and lead to unsafe design. Finally, three tested piles are analyzed to demonstrate the probabilistic analysis of piles by considering the spatial correlation of SPT data and the procedure for probabilistic analysis of pile bearing capacity is summarized.


2020 ◽  
Vol 10 (9) ◽  
pp. 3111 ◽  
Author(s):  
Visar Farhangi ◽  
Moses Karakouzian ◽  
Marten Geertsema

Liquefaction is a hazardous seismic-based phenomenon, which causes an abrupt decrease in soil strength properties and can result in the massive destruction of the built environment. This research presents a novel approach to reduce the risk of soil liquefaction using jet-grouted micropiles in clean sands. The saturated soil profile of the study project mainly contains clean sands, which are suitable to more reliably employ simplified soil liquefaction analyses. The grouting is conducted using 420 micropiles to increase the existing soil properties. The effect of jet grouting on reducing the potential of liquefaction is assessed using the results of the cone penetration test (CPT) and the standard penetration test (SPT), which were conducted before and after jet grouting by implementing micropiles in the project sites. According to three CPT-based liquefaction analyses, the Juang method predicts the most effective improvement range of the factor of safety in the clean sand. The Boulanger and Idriss, and Eurocode methods show comparable evaluations. Results of the SPT-based analyses show the most considerable increase of the factor of safety following the Boulanger and Idriss, and NCEER approaches in the SP soil. CPT- and SPT-based analyses confirm the effectiveness of jet grouting by micropiles on enhancing soil properties and reducing the risk of liquefaction.


Geo-Risk 2017 ◽  
2017 ◽  
Author(s):  
Salahudeen A. Bunyamin ◽  
Ijimdiya S. Thomas ◽  
Eberemu O. Adrian ◽  
Osinubi J. Kolawole

2017 ◽  
Vol 8 (3) ◽  
pp. 143
Author(s):  
Rifki Asrul Sani

ABSTRAKSeiring dengan terjadinya longsoran di beberapa titik wilayah di bukit Hambalang, maka diperlukan kajian data kondisi geologi teknik berupa sifat fisik dan mekanik tanah serta batuan bawah permukaan, terutama mengenai daya dukung tanah dalam menahan beban bangunan di atasnya agar tidak terjadi penurunan. Metode yang digunakan dalam penelitian ini dibagi menjadi tiga, yaitu metode penelitian studio dengan memanfaatkan data-data sekunder yang telah ada, metode penelitian di lapangan melalui pemetaan geologi untuk mendapatkan data litologi yang tersingkap di permukaan, zonasi longsoran yang terjadi, dan identifikasi kekuatan tanah hasil pemboran geoteknik dengan Standard Penetration Test (SPT), serta metode penelitian di laboratorium untuk mendapatkan parameter sifat fisik dan mekanik tanah sebagai penunjang data daya dukung tanah serta geologi teknik daerah penelitian. Hasil perhitungan fondasi dangkal untuk general soil shear condition dan local soil shear condition dapat disimpulkan bahwa daya dukung tanah yang diizinkan (qa) untuk setiap kedalaman yang paling tinggi pada fondasi bujur sangkar (square footing) dan nilai tertinggi yang terdapat pada kedalaman 2 m, yaitu 57,32 ton/m2 dan 36,11 ton/m2. Fondasi yang paling rendah untuk semua kedalaman pada fondasi menerus (continuous footing) untuk kedalaman 2 m memiliki nilai 34,49 ton/m2 dan 21,25 ton/m2. Berdasarkan data SPT, nilai daya dukung yang diizinkan (qa) pada masing-masing titik bor berkisar pada rentang 2,85 ton/m2 sampai 16,85 ton/m2. Kata kunci: longsoran, daya dukung, Standard Penetration Test (SPT). ABSTRACTAlong with the landslide in some areas on the Hambalang Hill, it needs data of engineering geological study such as mechanical and physical properties of soil also subsurface rocks. Especially regarding the soil bearing capacity in order to restrain the building from settlement. There are three methods which used in this research, those are studio research by using secondary data, fieldwork research that is geological mapping conducted to obtain data on lithological rocks at surface, landslide zone and soil strength identification from geotechnical drilling with Standard Penetration Test (SPT) and laboratory research to obtain the soil parameters of physical and mechanical properties, which used to support soil bearing capacity data and engineering geology in research area. The calculation results of the shallow foundation for general soil shear condition and the local soil shear condition it could be concluded that the allowable bearing capacity for all depth which is highest at the square footing and the highest value found to a depth of 2 m, that is 57.32 ton/m2 and 36.11 ton/m2. The lowest foundation for all the depth of the continuous footing to a depth of 2 m had value 34.49 ton/m2 and 21.25 ton/m2. Based on data from SPT, the allowable bearing capacity on each of borehole ranging from 2.85 ton/m2 to 16.85 ton/m2. Keywords: landslide, bearing capacity, Standard Penetration Test (SPT).


2017 ◽  
Vol 36 (3) ◽  
pp. 671-676
Author(s):  
JA Sadeeq ◽  
AB Salahudeen

Strength characteristics of foundation soils in the Permanent site of the Federal University Lokoja in Kogi State were evaluated based on standard penetration test (SPT) results using some conventional analytical models proposed by different researchers. The study was carried out in order to take precise engineering decisions on the type of foundations suitable for the proposed structures and to determine the optimal depth of foundation embedment.  The SPT N-values were first corrected to the standard average energy of 60% (N60) before they were used to correlate soil properties. Evaluation of the soil properties were done at foundation embedment depths of 0.6, 2.1 and 3.6 m. Results show that bearing capacity generally increased with boring depth. Based on the Meyerhof allowable bearing pressure estimation method, foundation pressures in the range of 150 – 600  kN/m2 were evaluated for use in the study area at shallow depths (depths in the range of 0.6 - 3.6 m).http://dx.doi.org/10.4314/njt.v36i3.2


2011 ◽  
Vol 71-78 ◽  
pp. 3308-3311
Author(s):  
Xiang Ruan ◽  
Ren Yu Zuo

Though the wide applications of jacked pile in engineering in Shenyang district, the problem is also exist in engineering for the capacity of the jacked pile is hard to account. The relationship between the standard penetration test and the ultimate vertical bearing capacity of jacked pile is established in this paper; also an empirical formula is put forward for calculating the ultimate vertical bearing capacity of the jacked pile in this district with blow count of standard penetration test (SPT). The engineering examples indicated that the empirical formula is feasible because the calculating bearing capacity of the silent pipe pile is coincided with the static load tests. The calculated results satisfy the engineering requirement andt can be concluded that the method is also convenient to choose the diameter and length of the pile during the initial stage of design.


2018 ◽  
Vol 14 (2) ◽  
Author(s):  
Marcos Fábio Porto de Aguiar ◽  
Fernando Feitosa Monteiro ◽  
Francisco Heber Lacerda de Oliveira ◽  
Yago Machado Pereira de Matos

RESUMO: Em meio aos diversos métodos utilizados no Brasil para determinação da capacidade de carga de fundações, a grande maioria parte do índice de resistência à penetração (NSPT). Para o caso de pequenas edificações, devido a fatores geralmente econômicos, a experiência ou a prática regional costumam prevalecer. Sendo assim, são elaborados, muitas vezes, projetos sem um procedimento de cálculo fundamentado em parâmetros comprovados por ensaios geotécnicos, podendo ocasionar problemas na edificação, como recalques excessivos, ou, até mesmo, comprometer a segurança da estrutura. Dessa forma, técnicas mais simples e de baixo custo, como o DPL (Dynamic Probing Light), podem ser uma opção para situações de pequenas cargas, viabilizando projetos fundamentados em ensaios in situ. Partindo de investigações com o DPL, este trabalho tem o objetivo de dimensionar fundações superficiais e profundas para edificações de pequeno porte através de algumas das principais metodologias disponíveis na literatura e verificar a sua eficiência. Por meio de resultados de campanhas de sondagens SPT (Standard Penetration Test) e DPL no campo experimental da Universidade de Fortaleza (UNIFOR), determinou-se a capacidade de carga de fundações superficiais e profundas fazendo aplicação dos índices NSPT e NSPT equivalente obtido pela correlação com o DPL. Identificou-se que essa correlação apresentou coeficiente de determinação satisfatório entre os parâmetros obtidos nos ensaios SPT e DPL para o terreno em questão, mostrando-se o DPL ser uma alternativa pertinente, em termos técnicos para projetos de fundações de obras de pequeno porte.ABSTRACT: Among the various methods used in Brazil of the determination of the bearing capacity on foundations, most part uses the standard penetration resistance (NSPT). For small constructions, due to economic factors generally, experience or regional practice usually prevails. Thus, projects without a reasoned calculation procedure in parameters supported by geotechnical tests are often designed, and may cause problems in the building, as excessive settlements, or even compromise the safety of the structure. In this way, simple and low cost techniques such as DPL (Dynamic Probing Light) may be an option for small loads situations, enabling projects based on in situ tests. This paper proposes to calculate the dimensions of shallow and deep foundations for small constructions and check its efficiency using DPL tests. Through the results of SPT (Standard Penetration Test) and DPL tests in the experimental field of the University of Fortaleza (UNIFOR), the determination of the bearing capacity in shallow and deep foundations was done using NSPT index and equivalent NSPT index obtained by the correlation with DPL. A correlation with satisfactory coefficient of determination was obtained between SPT and DPL tests parameters for the analyzed field, showing up the DPL as an appropriate alternative in technical terms for foundation design of small constructions.


2021 ◽  
Vol 11 (1) ◽  
pp. 45-64
Author(s):  
Duong Hong Tham ◽  
Truong Nhu Manh

Nowadays, in situ tests have played a viable role in geotechnical engineering and construction technology. Besides lab tests conducted on undisturbed soil samples, many different kinds of in-situ tests were used and proved to be more efficient in foundation design such as pressuremeter PMT, cone penetration test CPT, standard SPT, etc. Among them, a standard penetration test (SPT for short) is easy to carry out at the site. For decades, it has proved reliable to sandy soil, but many viewpoints and opinions argued that the test was not appropriately applicable to cohesive soil because of scattered and dispersed data of SPT blow counts through different layers. This paper firstly studies how reliable the SPT data can predict the physical and mechanical properties; secondly, the soil strength is determined in terms of corrected N-SPT values, and finally the bearing capacity of a pile penetrating cohesion soil. By analyzing data from 40 boreholes located in 18 projects in Ho Chi Minh City, South VietNam, coefficients of determination between SPT numbers and physical and mechanical properties of different soil kinds are not the same: R2 = 0.623 for sand, =0.363 for sandy clay and =0.189 for clay. The spatial variability of soil properties is taken into account by calculating the scale of fluctuation θ=4.65m beside the statistically-based data in horizontal directions. Finally, the results from two theoretical approaches of predicting pile bearing capacity were compared to those of finite element program Plaxis 3D and static load test at site. Correlation between the capacity computed by using corrected N-values instead of soil strength and results of static load test has proved to be well suitable in evaluating the bearing capacity of driven and jack-in piles, particularly installing in the cohesive soil using the SPT blows.


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