A study on the Effect of Distorted Sampler Shoe on Standard Penetration Test Result in Cohesionless soil

This paper describes the behaviour of two test piles (one bored and postgrouted and one simply bored, both 31.7 m long and 0.75 m in diameter) subjected to horizontal loads. These full-scale pile tests were carried out for the actual design of the pile foundation of a pier of the Evripos cable-stayed bridge. This bridge will link the Euboea Island to mainland Greece. The two piles have already been subjected to bearing capacity tests under axial loadings. The inclinometer measurements, taken during the present tests, yielded, in particular, the deformed shape of the piles as well as the bending moments. Conclusions could be drawn for the final design of the pile foundation with respect to horizontal loadings. Furthermore, various calculation methods using p–y reaction curves for cohesionless soils have been checked: the Ménard pressuremeter method, the method of the American Petroleum Institute recommendations, and the Standard penetration test method of Christoulas. These pile tests show that simple measurements, taken on construction sites, can yield interesting results on the actual behaviour of horizontally loaded piles. Key words : pile, horizontal loading, full-scale test, horizontal loads, bending moment, subgrade reaction modulus, p–y curve, cohesionless soil, Standard penetration test, pressuremeter test.

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Design load of rigid footings on sand

Canadian Geotechnical Journal ◽

10.1139/t09-145 ◽

2010 ◽

Vol 47 (8) ◽

pp. 872-884 ◽

Cited By ~ 2

Author(s):

Edgar G. Diaz ◽

Fernando Rodríguez-Roa

Keyword(s):

Standard Penetration Test ◽

Design Criterion ◽

Cohesionless Soil ◽

Unit Weight ◽

Embedment Depth ◽

Penetration Test ◽

Soil Pressure ◽

In Situ Tests ◽

Vertical Loading ◽

Design Load

Experimental evidence has shown that most current methods are not able to predict design loads of footings on cohesionless soil with an acceptable degree of accuracy. In the present study, a simple and realistic settlement-based method is proposed to estimate the design load of rigid footings on sand subjected to static vertical loading. The design criterion based on restricting the end-of-construction settlement to 16 mm because of the inherent variability of the real soil deposits is herein adopted. A series of finite-element analyses based on an advanced constitutive model were carried out to study the load–settlement response of footings supported on 14 sandy soils. Routine design charts were developed to predict the net allowable soil pressure of footings on normally consolidated and overconsolidated sands. These charts consider footing shape, embedment depth, grain diameters D10 and D60, particle shape, unit weight (or submerged unit weight for saturated sands), and indirect measurements of the shear strength derived from in situ tests, such as relative density, standard penetration test (SPT) or cone penetration test (CPT). As shown, the proposed charts match well with available experimental data.

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Assessment of the range of variation of Nγ from 60 estimation methods for footings on sand

Canadian Geotechnical Journal ◽

10.1139/cgj-2012-0426 ◽

2013 ◽

Vol 50 (7) ◽

pp. 793-800 ◽

Cited By ~ 12

Author(s):

Edgar Giovanny Diaz-Segura

Keyword(s):

Friction Angle ◽

Standard Penetration Test ◽

Estimation Methods ◽

Penetration Test ◽

In Situ Tests ◽

Vertical Loading ◽

Simplified Method ◽

Bearing Capacity Factor ◽

Range Of Variation

The range of variation of the bearing capacity factor, Nγ, was assessed using 60 estimation methods for rough footings on sand subjected to static vertical loading. The influence on the Nγ values of the use of correlations for the estimation of the friction angle, [Formula: see text], derived from in situ tests was also assessed. The analysis shows a marked dependency on the methods used to determine Nγ, showing differences for the same [Formula: see text] values of up to 267% between estimated values. Uncertainty in the estimation of [Formula: see text], due to the use of correlations with in situ tests, leads to a range of variation for Nγ higher than that seen using the 60 estimation methods. Finally, given the regular use of the in situ standard penetration test (SPT) on sands, and based on a series of analyses using finite elements, a simplified method in terms of the SPT N-values is proposed for estimation of Nγ in footings on sands.

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Discussion of “Standard Penetration Test: Its Uses and Abuses”

Journal of the Soil Mechanics and Foundations Division ◽

10.1061/jsfeaq.0000869 ◽

1966 ◽

Vol 92 (3) ◽

pp. 103-105

Author(s):

James D. Parsons

Keyword(s):

Standard Penetration Test ◽

Penetration Test

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Assessment of Dynamic Responses of Skin Simulant in a Drop Weight Penetration Test

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.715.33 ◽

2016 ◽

Vol 715 ◽

pp. 33-38

Author(s):

Jonas A. Pramudita ◽

Masashi Kato ◽

Yuji Tanabe

Keyword(s):

Penetration Depth ◽

Assessment Method ◽

Dynamic Responses ◽

Curvature Radius ◽

Penetration Test ◽

Static Test ◽

Drop Weight ◽

Weight Test ◽

Drop Weight Test ◽

Test Result

Skin laceration injury caused by a penetration of small curvature edge frequently occurs in a domestic accident. An assessment method for this injury is necessary in order to develop a safer manufactured product. To assess the risk of skin laceration injury in a penetration accident, a skin simulant made from silicone rubber was proposed. However, mechanical responses of this skin simulant under dynamic penetration loading have not yet been investigated. In this study, a drop weight penetration test device was developed in order to simulate penetration accidents under impact velocities of over 1 m/s. The device was then used for investigating the dynamic responses of skin simulant against several blades with different tip curvature radii. Load, penetration depth, impulse and energy at rupture were then determined from the test results. Load and penetration depth at rupture increased with the increase of tip curvature radius of the blades. Furthermore, the drop weight test result showed larger response compared to the quasi-static test result which might be caused by the viscous effect and the polymer characteristics such as cross-linking of the skin simulant.

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GEOTECHNICAL PARAMETERS STUDY USING SEISMIC REFRACTION TOMOGRAPHY

Jurnal Teknologi ◽

10.11113/jt.v78.9645 ◽

2016 ◽

Vol 78 (8-6) ◽

Cited By ~ 1

Author(s):

Rose Nadia ◽

Rosli Saad ◽

Nordiana Muztaza ◽

Nur Azwin Ismail ◽

Mohd Mokhtar Saidin

Keyword(s):

Parameter Estimation ◽

Seismic Refraction ◽

Standard Penetration Test ◽

P Wave ◽

Cohesive Soils ◽

Penetration Test ◽

Geotechnical Parameters ◽

Wave Velocities ◽

Refraction Tomography ◽

Loose Medium

In this study, correlation is made between seismic P-wave velocities (Vp) with standard penetration test (SPT-N) values to produce soil parameter estimation for engineering site applications. A seismic refraction tomography (SRT) line of 69 m length was spread across two boreholes with 3 m geophones spacing. The acquired data were processed using Firstpix, SeisOpt2D and surfer8 software. The Vp at particular depths were pinpointed and correlated with geotechnical parameters (SPT-N values) from the borehole records. The correlation between Vp and SPT-N values has been established. For cohesive soils, it is grouped into three categories according to consistencies; stiff, very stiff and hard, having velocity rangesof 575-314 m/s, 808-1483 m/s and 1735-2974 m/s, respectively. For non-cohesive soils, it is also divided into three categories based on the denseness as loose, medium dense and dense with Vp ranges of 528-622 m/s, 900-2846 m/s and 2876-2951 m/s, respectively

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A new genetic programming model for predicting settlement of shallow foundations

Canadian Geotechnical Journal ◽

10.1139/t07-063 ◽

2007 ◽

Vol 44 (12) ◽

pp. 1462-1473 ◽

Cited By ~ 66

Author(s):

Mohammad Rezania ◽

Akbar A. Javadi

Keyword(s):

Genetic Programming ◽

Programming Model ◽

Standard Penetration Test ◽

Shallow Foundations ◽

Penetration Test ◽

Case Histories ◽

Contributing Factors ◽

Artificial Neural Network Ann ◽

Gp Model ◽

Very High

In this paper, a new genetic programming (GP) approach for predicting settlement of shallow foundations is presented. The GP model is developed and verified using a large database of standard penetration test (SPT) based case histories that involve measured settlements of shallow foundations. The results of the developed GP model are compared with those of a number of commonly used traditional methods and artificial neural network (ANN) based models. It is shown that the GP model is able to learn, with a very high accuracy, the complex relationship between foundation settlement and its contributing factors, and render this knowledge in the form of a function. The attained function can be used to generalize the learning and apply it to predict settlement of foundations for new cases not used in the development of the model. The advantages of the proposed GP model over the conventional and ANN based models are highlighted.

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