Schmertmann Method Research Articles

Comparative geotechnical analysis for ultimate bearing capacity of precast concrete piles using cone resistance measurements

Abstract Computing the axial load capacity of pile foundations is often challenging for geotechnical engineers. Different theoretical and empirical approaches were proposed for determining the ultimate bearing capacity. Among these approaches, the in situ testing methods are based on cone penetration test (CPT) measurements. This study compares five CPT methods in estimating the axial load capacity of precast concrete piles evaluated at four piling construction projects in Northwest and Central Florida. The analytical methods used in this work are the Aoki and De Alencar method (1975), the Schmertmann method (1978), the Bustamante and Gianeselli Laboratoire Central des Ponts et Chausees method (1982), the Eslami and Fellenius method (1997), and the Eurocode 7 (2007). The outcomes indicated that the Eurocode method 7 had the most increased load capacity estimates, whereas the Eslami and Fellenius method yielded the lowest estimates. The results also indicated that the Aoki and De Alencar (1975) method consistently demonstrated the slightest differences among these values, showing its potential for reliable and consistent pile-bearing capacity estimations.

Analysis of Soil Characteristics by Layer Based on the Robertson Et Al and Schmertmann Method from CPT (Cone Penetration Test)

Analysis of Soil Characteristics by Layer Based on the Robertson Et Al and Schmertmann Method from CPT (Cone Penetration Test)

The Bearing Capacity Analysis of Deep Foundation based on In-situ Dynamic Penetration Test Compared to Pile Driving Analyzer (PDA)

On road/ bridge construction, foundation stability analysis is carried out by reviewing the bearing capacity. At the planning stage, this aspect can be calculated based on empirical and numerical methods using In-situ Dynamic Penetration Test data. Meanwhile, at the implementation stage, the bearing capacity results are checked using Pile Driving Analyzer (PDA). Hereinafter, the bearing capacity result in the field is compared with the bearing capacity result at the planning stage whether they are appropriate or not. In this study, the results of bearing capacity based on empirical using Meyerhoff and Schmertmann and numerical methods using MIDAS GTS NX were compared with the results of the PDA test. This study takes an overview of the Semarang – Demak Toll Road Development Project Package 2 STA 16 + 075. The analysis was carried out based on three STA points. The results obtained show that the largest deviation value is when the PDA result is compared with the Schmertmann method, which is 0.59 and the smallest deviation is when comparing PDA with MIDAS 0.03. Both deviations are located on P 133F STA 16+711. This different deviation is due to the ultimate bearing capacity analysis based on empirical equations that only analyze single piles based on the original soil properties, while the MIDAS analysis also considers pile parameters and interface parameters. Moreover, in the PDA test, there are factors of environmental conditions.

Elastic Solutions to 2D Plane Strain Problems: Nonlinear Contact and Settlement Analysis for Shallow Foundations

The classical Neumann boundary value problem of an isotropic, homogeneous elastic half-plane under plane strain conditions is readdressed as the limiting case of the fully three-dimensional problem. Analytical solutions of the stress and strain tensors are obtained by taking the limit from known three-dimensional solutions. It is shown that the displacement fields for the plane strain problem are not well defined. A small number of simple expressions are developed, which provide a general solution for linearly-varying traction over arbitrary regions on the boundary. A simple, efficient, and rapidly convergent algorithm is developed which uses these solutions as analytic elements and provides a solution approach to the general boundary value problem. The method is verified against known solutions for Hertzian contact between parallel cylinders. Two numerical examples are presented for the analysis of shallow foundation systems. In the first, the boundary conditions are informed by analytical elastoplastic calculations and a strain influence analysis is performed and compared with the Schmertmann method. Subsequently, empirical laboratory contact traction distributions measured by Bauer et al., in both the normal and tangential directions are employed as boundary conditions for an analysis of the underlying stress field.

The Comparison of Pile Bearing Capacity using 8 Direct Method based on CPT data in Surabaya Area

This research focuses on comparing the pile bearing capacity resulting from eight different methods that have been developed and are widely used in design. The methods used are the Schmertmann (1978), LCPC (Bustamante & Gianeselli 1982 – Laboratoire Central des Ponts et Chausees), De Ruiter and Beringen (1979), Tumay and Fakhroo (1982), Price and Wardle (1982), Philipponnat (1980), Aoki and De Alencar (1975), and the Penpile methods (Clisby et al 1978). CPT data is used in this study because it is considered easier, faster and fast and relatively economical, and supplies continuous records with depth. Twenty different CPT data variations in the Surabaya area were used in this study. The piles used in this study are concrete piles with a diameter of 60 cm. The result of this research is that the bearing capacity using the Schmertmann method tends to be greater when compared to other methods while the Penpile method produces the lowest carrying capacity. The ratio of the minimum and maximum carrying capacity of the 8 methods used is up to 20%.

Analisis Dan Desain Dinamis Pondasi Dangkal Berdasarkan Data CPT

Generator set yang digunakan pada gedung harus memperhatikan beberapa faktor lingkungan, sedemikian sehingga tidak mempengaruhi sistem struktur bangunan dan tidak menimbulkan kebisingan-kebisingan pada saat atau waktu operasi. Untuk menghindari beberapa gangguan tersebut, seluruh sistem pondasi tidak hanya dianalisis dan didesain dalam kondisi statis saja, akan tetapi juga harus mempertimbangkan beberapa faktor dampak akibat beban dinamis. Tujuan studi ini adalah menentukan dimensi-dimensi pondasi dangkal dan spesifikasi karet sebagai suatu peredam getaran sesuai dengan peraturan yang berlaku. Dalam studi ini, perhitungan statis menganalisis penurunan segera dan konsolidasi, serta daya dukung tanah yang terjadi pada lapisan tanah pondasi dengan menggunakan metode Schmertmann. Analisis dinamis menghitung besaran frekuensi dan amplitudo, dan juga atenuasi vibrasi tunggal dan gabungan dalam arah pergerakan vertikal, horizontal, dan longitudinal; kemudian juga akibat putaran momen dari pergoyangan rocking, yawing, dan pitching dengan metode Lumped Parameter dari beberapa literatur. Analisis dan desain telah menghasilkan dimensi 3,7 * 1,7 * 0,7 m untuk sistem pondasi dangkal dan daya dukung ijin (qall) menunjukkan = 4,10 kg/cm2 berdasarkan kondisi statis dan 6,20 kg/cm2 berdasarkan kondisi statis dan dinamis, secara berurutan. Kemudian, beberapa perkiraan di dalam perhitungan kondisi statis dan dinamis juga mendapatkan penurunan total (D) = 0,49 mm, amplitudo (Az) = 6,6 x 10-6 m, (Ax) = 3,2 x 10-6 m, (Af) = 1,7 x 10-6 rad. Secara umum, parameter-parameter yang dihasilkan dari analisis dan desain tersebut telah memenuhi peraturan-peraturan standar dan pemerintah setempat yang ada.

Evaluation of Ultimate Bearing Capacity of Pre-Stressed High-Strength Concrete Pipe Pile Embedded in Saturated Sandy Soil Based on In-Situ Test

Estimation of ultimate bearing capacity (UBC) of pre-stressed high-strength concrete (PHC) pipe pile is critical for optimizing pile design and construction. In this study, a standard penetration test (SPT), static cone penetration test (CPT) and static load test (SLT) were carried out to assess, determine and compare the UBC of the PHC pipe pile embedded in saturated sandy layers at different depths. The UBC was calculated with three methods including the JGJ94-2008 method, Meyerhof method and Schmertmann method based on in-situ blow count (N) of SPT (SPT-N) which was higher than the values recommended in survey report regardless of pile length. The average UBC values calculated with cone-tip resistance and sleeve friction from CPTs was also higher than the value recommended in the survey report. Moreover, the actual UBC values directly obtained by load-displacement curves from SLTs were in line with the calculated values based on in-situ SPTs and CPTs, but approximately twice as high as the values recommended in the survey report regardless of pile length. For the SPT method, the application of bentonite mud in saturated sand layers is critical for the assessment of pile capacity in the survey phase, CPTs can provide reliable results regardless of soil characteristics and groundwater if the soil layer can be penetrated, and SLTs are necessary to accurately determine the UBC in complex stratum.

Analysis of Adolescent Fertility Aged 10-14 Calculation Results in Indonesia

The adolescent's fertility aged 10-14 years is one of the national and international focus of attention as outlined in Sustainable Development in 2030 target 3.7. To fulfill these targets, there is 3.7.2 indicator regarding adolescent fertility (10-14 and 15-19 years). The indicator that was used to measure adolescent fertility is the Age-Specific Fertility Rate (ASFR). The availability of information about this indicator can help the stakeholders to understand their current situations and their needs in order to prepare for healthier adolescence and adulthood. So far, there is not much information about ASFR 10-14. Usually, ASFR is calculated for aged 15-49 years. It is because of adolescent fertility aged 10-14 are very rare cases and the data sources that can be used to calculate them are limited. The aim of this study is to calculate ASFR aged 10-14 years in Indonesia use the 2012 IDHS, 2015 inter-census population survey, and the 2017 IDHS data. The methods used are direct method, a direct method with modification, and Schmertmann method. Based on calculations from three methods, it can be concluded that ASFR aged 10-14 years in Indonesia is still very low (under 1 per 1000 births). That can be interpreted that not many birth cases are found for women aged 10-14 years in Indonesia.

A Method for Predicting Pile Capacity Using Cone Penetration Test Data

The massive construction in poor lands has encouraged engineers to use deep foundations in order to transfer superstructure loads to the subsoil. Since soil excavation, sampling, and laboratory testing as a part of site investigation are relatively difficult, in-situ tests such as cone penetration test (CPT) as a very informative test may be recommended. The CPT has been widely used in engineering as a part of site investigation, and its data has been used to determine the axial capacity of piles. In this paper, the prediction capability of three empirical widely famous old methods used to predict the axial pile capacity based on CPT data is evaluated by using field data obtained from direct field pile loading tests. In this evaluation, the direct pile load test results are used as measured data. Three popular famous statistical evaluation methods namely the best-fitted line, geometric mean, and geometric standard deviation have been used. The evaluation results indicate that generally although predicting methods based on CPT data have been widely used to determine the axial bearing capacity of piles, they need to be upgraded for the economic and relatively accurate design of piles. According to the statistical studies carried out in the current research, among three old empirical methods, although the Nottingham and Schmertmann Method (1975, 1978) (NSM) [7, 8] has the best agreement with test results, it is felt that the method needs to be upgraded. The modification of NSM has been done in the current paper using a comprehensive database.

CAPACITY ANALYSIS OF SINGLE PILE BEARING CAPACITY BASED ON STATIC METHOD AND N-SPT TEST ON PILE DRIVING ANALYZER TEST (CASE STUDY OF PT. ASAHI FORGE INDONESIA PHASE II PROJECT)

Soil investigation has an important role before building a building. The carrying capacity of the soil obtained from the results of soil investigations is very influential on the shape and dimensions of the foundation itself. In the PT.Asahi Forge Indonesia Project, the SPT test data is out of sync with the actual piling results related to embedded pile penetration. The design plan for piles with a length of 7 m based on the N-SPT test turned out that in the field, the piles achieved a bearing capacity at a depth of 9 meters. The final project aims to analyze and compare the carrying capacity of a single pile based on static methods and N-SPT test on the Pile Driving Analyzer. The method used in this research is the study method of laboratory test results and N-SPT. Work steps include; preparation, literature study, data collection, carrying capacity analysis, and comparison of analysis results. The results of the analysis of the carrying capacity of the piles based on the static method by the (Vijayvergiya & Focht, 1974) method amounted to 549,201 kN; The (McClelland, 1974) Method of 426,292 kN; The U.S Army Corps Method is 459,545 kN and the Tomlinson (1977) Method is 474,191 kN. While the results of N-SPT were bearing piles bearing capacity with the Mayerhof (1956) method of 738,645 kN and the Schmertmann (1967) Method of 451,327 kN. Based on these results, the N-SPT test based on the Mayerhof (1956) Method of 738,645 kN was the closest to the PDA test results of 755,116 kN. The comparison of the results of the analysis between the static test, N-SPT and PDA test is 19: 24: 30. This means that the carrying capacity of the static pile and PDA test has a difference of 37% while between the N-SPT and PDA test has a difference of 20%.

Perencanaan Jembatan Rangka Baja Pelengkung Sungai Liong

Bengkalis government do project to build Liong river bridge with construction type is concrete arch bridge. But at relatively new service time, there was a big deflection in one of bridge segments. In this research will be design the bridge with steel arch bridge type.
 Bridge design using RSNI T-02-2005 about bridge load standard. For steel frame design refers to RSNI T-03-2005, and concrete structure design refers to RSNI T-12-2004. In piles calculation, using the Schmertmann method.
 The results of top structure design is top chord using WF.305.305.22.35, bottom chord WF. 305.305.39.63, diagonal chord WF.305.305.22.35, vertical hanger WF 203.203.10.17, wind bracing WF.203.203.8.12, truss bracing WF.203.203.8.12, girder using WF.400.200.8.13, cross girder WF.500.200.10.16, and the main girder using WF.500.200.10.16 profile. The results of bottom structure design is abutment width of 9,3 m and abutment length of 11 m. Using concrete piles with diameter of 50 cm, length 20 m and 28 point of stake. The largest deflection of bridge is 118,72 mm. This deflection is still safe because the value smaller than tolerance deflection L/240, which is 458,33 mm. The most compatible construction method for liong II river bridge is temporary coloumn method.

Reliability and construction control of vibro piles

Abstract The goal of this study was to determine the most reliable and efficient combination of design and construction methods required for vibro piles. For a wide range of static and dynamic formulas, the reliability-based resistance factors were calculated using EGYPT database, which houses load test results for 318 piles. The analysis was extended to introduce a construction control factor that determines the variation between the pile nominal capacities calculated using static versus dynamic formulae. From the major outcomes, the lowest coefficient of variation is associated with Davisson’s criterion, and the resistance factors calculated for the AASHTO method are relatively high compared with other methods. Additionally, the CPT-Nottingham and Schmertmann method provided the most economic design. Recommendations related to a pile construction control factor were also presented, and it was found that utilizing the factor can significantly reduce variations between calculated and actual capacities.

Determination of Ultimate Pile Bearing Capacity from a Seismic Method of Shear Wave Velocity in Comparison with Conventional Methods

The seismic method in the ultimate bearing capacity of piles based on shear wave velocity measurement is a new technique in geotechnical engineering design. In this study, the value of shear wave velocity, Vs is being successfully used to formulate a theory to determine the ultimate bearing capacity of piles. This theory is adapted from the ultimate bearing capacity of shallow foundation proposed by Keceli. Keceli’s formula is adapted by equating the pile tip vertical resistance of the seismic formula to the end bearing capacity of the pile tip for each layer. The sum of half the vertical resistance of each layer is then equated to the total shaft resistance of the pile. The end tip is then added to the total shaft resistance to give the total ultimate pile bearing capacity of the pile. This study was conducted at three sites, two sites of residual soil located in Malaysia and one site of alluvial soil situated at Collierville, Tennessee, USA. The results of the adapted seismic formula were compared with the static pile bearing capacities calculated using conventional methods proposed by Meyerhof for the SPT-N values and the Schmertmann, Bustamante and Gianeslli method for the SCPTu values. The percentage error in the ultimate bearing capacity of the piles between the adapted seismic and the conventional methods for all the sites were found to be -4.77%, -3.01% and -0.93% at Hulu Langat, Mutiara Damansara and Collierville sites respectively.

On the evaluation of pre-consolidation pressure of undisturbed saturated clays

The objective of this research was to show the effect of sample disturbance on the values of pre-consolidation pressure бc by using Schmertmann method. A prediction of бc form pocket penetrometer is also achieved. This was carried out by comparing the values of бc that were estimated from the results of consolidation tests, with the readings of pocket penetrometer for same samples. Pocket penetrometer is a simple tool that can be easily used in field and laboratory to initially predict unconfined compressive strength for clayey soils. Before carrying out the consolidation tests on undisturbed samples, pocket penetrometer readings were recorded. The correlation obtained between pocket reading and бc values that resulted from consolidation tests was found to be valid for a wide range of clay stiffness, ranging between medium stiff to very stiff clay. As for soft clay, this correlation was found not to be applicable where its behavior is believed to be greatly affected by the degree of disturbance occurring to samples during drilling.

Allowable bearing capacity based on Schmertmann method for sandy soils

In this study, since the city of Bartin in Northwest Turkey on the Black Sea is in the first-degree seismic zone and its residential area only occupies 7% of the total acreage that is expected to expand with newly flourishing urbanization, soil samples were obtained from a total of five different locations where there are open areas for the construction of dwellings. Engineering properties of the soils were assessed by laboratory experiments and the allowable bearing capacity and elastic settlement (Schmertmann method) values of the soils were calculated. The results showed that calculated settlement values are very high and can damage the foundation systems of any building constructed in future; therefore, allowable settlement value was fixed at 50 mm and allowable bearing capacities of the soils were obtained from back calculations by using the Schmertmann method. The aim of calculating allowable bearing capacity modified by settlement analysis is to propose a procedure about the foundation designs of the building laying on compressible sandy soils. Key words: Shallow foundations, allowable bearing capacity, silty sand, Schmertmann method, settlement.

피조콘시험결과를 활용한 OCR결정법의 평가

The purpose of this study is to evaluate the capability of representative existing methods through which OCR of clayey soils can be predicted utilizing PCPT data. The existing methods include Schmertmann method, Chen and Mayne method using pore water pressures measured immediately behind the cone base , Lunne et al. method, and the latest Abu-Farsakh method. The lab. and in-situ test results, conducted in Incheon port area, were used for the study. The predicted OCR values from the methods were compared with the reference values estimated from laboratory oedometer test. Lunne et al.(k

Pullout capacity of small ground anchors by direct cone penetration test methods and neural networks

Marquees are temporary light structures that are connected to the ground by small anchors that act in tension and are designed to resist uplift forces. Due to the temporary nature of these structures, little, if any, attention is given to the pullout capacity of the anchors used to secure them. Failures of such structures are not rare and have resulted in deaths and tens of thousands of dollars of damage. This paper reports on a series of 119 in situ anchor pullout tests conducted on rough mild steel anchors of various lengths, cross-sectional shapes, and areas. Comparison tests are carried out to investigate the impact of the factors affecting the pullout capacity of small anchors. Six methods that determine the axial pile capacity directly from cone penetration test (CPT) data are presented and used to calculate the pullout capacity of small ground anchors. The capacities obtained from these CPT-based methods are compared with predictions from a recently developed artificial neural network (ANN) model. The actual pullout loads are compared with predictions from the CPT and ANN methods, and statistical analyses are carried out to evaluate and rank their performance. The results indicate that the ANN-based method provides superior predictions of the pullout capacity of small ground anchors, whereas the Schmertmann method provides the best performance of the CPT-based techniques examined.Key words: ground anchors, pullout capacity, cone penetration test, artificial neural networks.

Towards reliable and effective site investigations

It is widely appreciated that, in civil engineering and building projects, the largest element of financial and technical risk usually lies in the ground. Almost exclusively, the scope of geotechnical investigations is governed not by what is needed to characterise the subsurface conditions appropriately but, rather, by how much the client and project manager are willing to spend. There is often little correlation between the variability of the ground and the scope of the investigation. This paper presents the results of a Monte Carlo simulation incorporating many 3D single-layer soil profiles with different statistical characteristics. A three-storey building founded on nine pad footings is used to assess the reliability of various site investigation scopes and test methods. The pad footings are designed on the basis of settlement, and are examined using 3D finite element analysis and Schmertmann's method. It is observed, as expected, that the likelihood of underdesigning or overdesigning a footing decreases as the scope of the investigation increases. The relationship between these likelihoods and the variability of the ground is presented.

Towards reliable and effective site investigations

It is widely appreciated that, in civil engineering and building projects, the largest element of financial and technical risk usually lies in the ground. Almost exclusively, the scope of geotechnical investigations is governed not by what is needed to characterise the subsurface conditions appropriately but, rather, by how much the client and project manager are willing to spend. There is often little correlation between the variability of the ground and the scope of the investigation. This paper presents the results of a Monte Carlo simulation incorporating many 3D single-layer soil profiles with different statistical characteristics. A three-storey building founded on nine pad footings is used to assess the reliability of various site investigation scopes and test methods. The pad footings are designed on the basis of settlement, and are examined using 3D finite element analysis and Schmertmann's method. It is observed, as expected, that the likelihood of underdesigning or overdesigning a footing decreases as the scope of the investigation increases. The relationship between these likelihoods and the variability of the ground is presented.

DETERMINATION OF THE COEFFICIENT OF SECONDARY COMPRESSION ON RECONSTITUTED SAND BED/SMĖLINIO PAGRINDO ANTRINĖS DEFORMACIJOS KOEFICIENTO NUSTATYMAS

Experimental results on reconstituted sand bed are described to define the coefficient of secondary compression in sand. Two samples of Ticino sand were reconstituted at two different relative densities (DR ≅ 40 and 85%). The observed settlements have been compared to those inferred from a conventional computation Schmertmann method. This method provides an excellent provision of the primary settlement occurring in freshly deposited Ticino sand. The coefficient of secondary compression C αε was determined from the data of experimental results. Using the correlations regression analysis, dependences of C αε calculation are suggested. And equations (3) for low-density sand and (5) for high-density sand have been obtained. Equation (7) determines a common case. Equations (3), (5) and (7) were approbated by comparison of computed and observed [10] secondary settlements.