Comparison of California Bearing Ratio (CBR) Value  Based on Cone Penetration Test (CPT) and Dynamic Cone Penetrometer (DCP)

In civil engineering, land is important because as a place for building infrastructure to be built, so that the building infrastructure on it is stable, adequate carrying capacity is needed. The amount of soil bearing capacity can be determined in several ways, including the California Bearing Ratio (CBR) Field Test, Cone Penetration Test (CPT) and Dynamic Cone Penetrometer (DCP). The CBR and DCP tests are often used to determine the level of surface soil density on road structures, while CPT is usually used to determine the hard soil layer on the building structure. However, in certain situations Sondir and DCP data are often used to predict the CBR value, because the test is quite practical and efficient compared to the CBR test. CBR testing requires heavy equipment which in most small-scale projects is not available. In this study, we compared the CBR value based on the data obtained from the Sondir and DCP tests. Data collection was carried out in Surakarta and its surroundings. Based on the test results, the CBR value generated from the DCP test tends to be smaller than that from the CPT test with a ratio of 0.62: 1. This study resulted in the relationship between CBR values from the results of the CPT and DCP tests shown in the following equation: CBR (DCP) % = 0.2552 CBR(CPT) + 2.6306 and CBR (DCP) % = 0.617 CBR(CPT).

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Improvement of GPR Full-waveform inversion images using Cone Penetration Test data

Geophysics ◽

10.1190/geo2020-0283.1 ◽

2021 ◽

pp. 1-74

Author(s):

Zhen Zhou ◽

Anja Klotzsche ◽

Jessica Schmäck ◽

Harry Vereecken ◽

Jan van der Kruk

Keyword(s):

Waveform Inversion ◽

Cone Penetration Test ◽

Small Scale ◽

Inversion Method ◽

Full Waveform Inversion ◽

Penetration Test ◽

Cone Penetration ◽

Full Waveform ◽

Effective Source

Detailed characterization of aquifers is critical and challenging due to the existence of heterogeneous small-scale high-contrast layers. For an improved characterization of subsurface hydrological characteristics, crosshole ground penetrating radar (GPR) and Cone Penetration Test (CPT) measurements are performed. In comparison to the CPT approach that can only provide 1D high resolution data along vertical profiles, crosshole GPR enables measuring 2D cross-sections between two boreholes. Generally, a standard inversion method for GPR data is the ray-based approach that considers only a small amount of information and can therefore only provide limited resolution. In the last decade, full-waveform inversion (FWI) of crosshole GPR data in time domain has matured, and provides inversion results with higher resolution by exploiting the full recorded waveform information. However, the FWI results are limited due to complex underground structures and the non-linear nature of the method. A new approach that uses CPT data in the inversion process is applied to enhance the resolution of the final relative permittivity FWI results by updating the effective source wavelet. The updated effective source wavelet possesses a priori CPT information and a larger bandwidth. Using the same starting models, a synthetic model comparison between the conventional and updated FWI results demonstrates that the updated FWI method provides reliable and more consistent structures. To test the method, five experimental GPR cross-section results are analyzed with the standard FWI and the new proposed updated approach. Both synthetic and experimental results indicate the potential of improving the reconstruction of subsurface aquifer structures by combining conventional 2D FWI results and 1D CPT data.

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Calibration of a Miniature Cone Penetrometer for Highway Applications

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1614-02 ◽

1998 ◽

Vol 1614 (1) ◽

pp. 8-14 ◽

Cited By ~ 4

Author(s):

Pradeep U. Kurup ◽

Mehmet T. Tumay

Keyword(s):

Ground Improvement ◽

Cone Penetration Test ◽

Test System ◽

Soil Parameters ◽

Cone Penetrometer ◽

Penetration Test ◽

Cone Penetration ◽

Tip Resistance ◽

In Situ Investigation

The electronic cone penetrometer is an important in situ investigation tool of choice for site characterization. Application of this proven concept of the cone penetration test (CPT) to highway design and construction control by miniaturization is described. A miniature cone penetrometer with a projected cone area of 2 cm2 has been developed and implemented in a continuous intrusion miniature cone penetration test system (CIMCPT). This device may be used for rapid, accurate, and economical characterization of sites and to determine engineering soil parameters needed in the design of pavements, embankments, and earth structures. The miniature cone penetration test (MCPT) gives finer details than the standard 10-cm2 cross-sectional area reference cone penetrometer. This makes the MCPT attractive for subgrade characterization, quality-control assessment, compaction control of embankments, and assessment of ground improvement effectiveness for transportation infrastructure. In situ calibration of the CIMCPT system was conducted at a highway embankment site in Baton Rouge, Louisiana. MCPT penetration profiles were compared with those obtained by using the standard cone penetrometer at the same site. The tip resistance of the MCPT was 10 percent higher than that of the reference CPT. The sleeve friction and friction ratio of the reference CPT were higher than that of the MCPT by 12 and 23 percent, respectively. Calibration was also performed to determine empirical cone factors required for estimating undrained shear strength from MCPT data.

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Cone penetration test calibration for Erksak (Beaufort Sea) sand

Canadian Geotechnical Journal ◽

10.1139/t87-074 ◽

1987 ◽

Vol 24 (4) ◽

pp. 601-610 ◽

Cited By ~ 23

Author(s):

K. Been ◽

B. E. Lingnau ◽

J. H. A. Crooks ◽

B. Leach

Keyword(s):

Beaufort Sea ◽

Cone Penetration Test ◽

Horizontal Stress ◽

Sand Sample ◽

Cone Penetrometer ◽

Calibration Data ◽

Penetration Test ◽

Cone Penetration ◽

Fines Content ◽

Calibration Chamber

Interpretation of the cone penetration test in sands is generally based on empirical calibrations from tests in large-diameter calibration chambers. Although interpretation of these calibration data for clean sands in terms of the state parameter is expected to be broadly applicable to other sands, material-specific correlations are desirable for many projects. This paper describes a series of calibration chamber tests carried out on a sand dredged from the Beaufort Sea for construction of artificial islands. This Erksak sand is a uniformly graded, subrounded medium-grained sand with a fines content of 3–6%. The testing chamber described is 1.4 m in diameter, and allows independent control of vertical, horizontal, and back pressures on the sand sample. Samples of the sand were prepared by moist compaction to preserve the fines content, and then back pressure saturated.The chamber test data are presented and confirm that the Erksak sand fits the general trends observed for other sands very well. A method is also described that allows the interpretation to be consistent, even in the event that nonuniform void ratios occur in the samples. Measurements of horizontal stress behind the cone tip, which is a new development in cone penetrometer testing, are also presented. Key words: cone penetrometer, sands, in situ tests, state, calibration chamber, horizontal stress measurement.

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The Consolidation State of Red Clay Determined by Cone Penetration Test

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.639-640.652 ◽

2013 ◽

Vol 639-640 ◽

pp. 652-656

Author(s):

Zhen Yu Li ◽

Qing Qing Tian ◽

Hong Bin Xiao

Keyword(s):

Laboratory Experiments ◽

Soil Depth ◽

Soil Layer ◽

Cone Penetration Test ◽

Penetration Test ◽

Cone Penetration ◽

Red Clay ◽

Foundation Soil ◽

Cone Penetration Tests ◽

Static Point

It is of significance to determinate the consolidation state of soil for evaluation of deformation and strength of foundation soil. The consolidation state of red clay is determined through laboratory experiments combined with static cone penetration tests. The results show that the law of consolidation history of red clay is opposite to other soils. The static point resistance obtained from cone penetration test decreases linearly with soil depth increasing. The over-consolidate rate of different soil layer gotten by laboratory experiments also decreases linearly with soil depth increasing. The slopes of two linear regress curves are similar. The change of static point resistance can be used to estimate over-consolidate rate of red clay at different depth.

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Analisis Potensi Likuifaksi Akibat Gempa Bumi Menggunakan Metode SPT (Standar Penetration Test) Dan Cpt (Cone Penetration Test) Di Kabupaten Bantul, Yogyakarta

Wahana Fisika ◽

10.17509/wafi.v2i1.7022 ◽

2017 ◽

Vol 2 (1) ◽

pp. 8 ◽

Cited By ~ 1

Author(s):

Tini Tini ◽

Adrin Tohari ◽

Mimin Iryanti

Keyword(s):

Soil Layer ◽

Cone Penetration Test ◽

Standard Penetration Test ◽

Silty Sand ◽

Penetration Test ◽

Cone Penetration ◽

Ground Acceleration ◽

Liquefaction Potential ◽

Liquefaction Hazard ◽

Better Than

Gempa bumi yang terjadi di daerah Bantul, Yogyakarta pada 27 Mei 2006 dengan magnitudo gempa bumi sebesar 6.3 SR dapat menyebabkan terjadinya bahaya likuifaksi yang dapat merusak bangunan khususnya di wilayah Bantul Yogyakarta. Investigasi geoteknik yang telah dilakukan di Bantul, Yogyakarta dapat memberikan gambaran lapisan tanah yang berpotensi terjadinya likuifaksi. Analisis potensi likuifaksi dilakukan berdasarkan data SPT (Standard Penetration Test) dan CPT (Cone Penetration Test) dengan percepatan maksimum tanah menurut Gutenberg Richter di daerah penelitian rata-rata bernilai sebesar 2.93 m/s2 dan menurut Donovan sebesar 2.88 m/s2. Hasil analisis penelitian menunjukan bahwa lapisan tanah yang berpotensi likuifaksi didominasi oleh jenis tanah pasir lanauan da lanau pasiran yang berada pada kedalaman 0.2 – 3 m, 0.4 m, 2.4 m, 3.6 m, 7.6 – 7.8 m dan 8.2 m. Pengaruh percepatan maksimum tanah menurut Gutenberg Richter lebih besar terhadap terjadinya likuifaksi daripada menurut Donovan. Perbandingan hasil analisis potensi likuifaksi antara data SPT (Standard Penetration Test ) dan CPT (Cone Penetration Test) pada daerah penelitian menunjukan adanya kesamaan potensi likuifaksi pada lapisan tanah dengan kedalaman yang sama diantaranya pada kedalaman 0.2 m-4 m, dengan nilai Cyclic Strees Ratio (CSR) rata-rata sebesar 0.2, sedangkan berdasarkan nilai Cyclic Resistance Ratio (CRR) terdapat perbedaan nlai. Analisis berdasarkan data CPT lebih baik daripada data SPT karena data CPT lebih rapat daripada data SPT.The earthquake that occurred in Bantul, Yogyakarta on May 27, 2006 with the magnitudo of the earthquake of 6.3 SR can caused liquefaction hazard which could damage to teh building in the municipals of Bantul, Yogyakarta. Geotechnical investigation was carried in Bantul Yogyakarta, can give information about liquefaction hazard in soil layer. The liquefaction potential lanalysis was conducted using SPT and CPT methods, with Gutenberg-Richter’s maximum ground acceleration is 2.93 m/s2 and Donovan’s maximum ground acceleration is 2.88 m/s2. Result of liquefaction analysis indicate that the soil layer domination of silty sand dan sandy silt at the depth of 0.2 – 3 m, 3.6 m, 4 m 7.6 – 7.8 m and 8.2 m. Gutenberg-Richter’s maximum ground acceleration having influential for liquefaction potential better than Donovan’s maximum ground acceleration. Ratio result of liquefaction was conducted using SPT same as soil layer with CPT in resech location at the depth 0.2 m-4 m, with value Cyclic Strees Ratio (CSR) is 0.2. Even value Cyclic Resistances Ratio (CSR) have different value. The liquefaction potential lanalysis was conducted using CPT method better than SPT methods.

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Numerical Simulation of Cone Penetration Tests Inside Suction Caisson Foundations in Sand

Volume 10: Offshore Geotechnics ◽

10.1115/omae2020-18721 ◽

2020 ◽

Author(s):

Marc Stapelfeldt ◽

Diaa Alkateeb ◽

Jürgen Grabe ◽

Britta Bienen

Keyword(s):

Cone Penetration Test ◽

Service Performance ◽

Small Scale ◽

Penetration Test ◽

Cone Penetration ◽

Soil Plug ◽

Suction Caisson ◽

Cone Penetration Tests ◽

Caisson Foundations ◽

Penetration Tests

Abstract Offshore wind is increasingly utilised as a renewable energy source. A growing number of bottom fixed wind turbines installed offshore are supported by suction caisson foundations. The suction-assisted installation remains a source of uncertainty towards the in-service performance due to the unknown post-installation soil plug state. Cone penetration tests within the suction caisson can help to improve the reliability. Therefore, cone penetration tests were employed in centrifuge tests to investigate the plug state in a previously installed suction caisson. However, the performance of a cone penetration test in a small-scale experiment is connected to uncertainties: A relatively large diameter device is required to conduct the cone penetration test — especially in a centrifuge test. Different finite element models are developed in order to visualise and investigate a cone penetration test inside a suction caisson. The numerical analysis results are validated through the back-calculation of centrifuge cone penetration tests. The results of the simulated cone penetration tests inside a suction caisson are evaluated and compared to the centrifuge experiments. This investigation reinforces the scope of the centrifuge experiments and emphasises a considerable effect of the pressure transferral through the caisson lid in the soil plug state. Hence, the results of this study reduce existing uncertainties regarding possible suction installation effects on the in-service performance of caisson foundations.

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