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Aims. The purpose of this work is to justify the reliability of the developed models of pile foundations on the data of field observers and to demonstrate the feasibility of using pile foundations to increase the stability and bearing capacity of the NPP structures foundation using the example of reactor building (RB). Methods. The data of field observers for the settlement of the RB are presented. The expressions for calculation of the static stiffness of the contact surface of the slab bottom and soil medium, as well as for pile foundations taking into account the effects of interaction of grillage and pile field with the soil media with a general character of displacement of a circular cross section pile are submitted. A spatial three-dimensional finite element static model of RB was developed together with the soil base. Isolines of vertical movements of RB fundamental slabs for natural foundations, as well as for pile foundations for normal operation are shown. A comparative analysis of the data of field observers with the calculation results allows us to justify the reliability of the developed model of the pile foundation. Results. The calculations of the foundation yield correspond to all the period of operation including construction, and the results of observations relate only to the period of operation that explain the difference. A comparative analysis of the data of field observers with the calculation results allows us to justify of the strong effectiveness of realization of pile foundation for the massive structures on soft soil bases.

Piles provide a convenient solution for heavy structures, where the foundation soil bearing capacity, or the tolerable settlement may be exceeded due to the applied loads. In cohesionless soils, the two frequently used pile installation methods are driving and drilling (or boring). This paper reviews the results of a large database of pile load tests of driven and drilled piles in cohesionless soils at various locations worldwide. The load test results are compared with the static analysis design method for single piles recommended in the Canadian Foundation Engineering Manual (CFEM) and other codes and standards such as the American Association of State Highway and Transportation Officials, Federal Highway Administration, American Petroleum Institute, Eurocode, and the Naval Facilities Engineering Command. An improved pile design procedure is proposed linking the pile design coefficients (β) and (Nt) to the friction angle of the soil, rather than employing the generalized soil type grouping scheme previously used in the CFEM. This improvement included in the new version of the CFEM 2021 produces a more unified value of the pile capacity calculated by different designers, reducing the obtained design capacity discrepancies.

The foundation is an important part of the building structure because it functions as a support. The selection of this pile foundation has various considerations, namely the pile foundation can achieve the hardest soil bearing capacity, made with a manufacturing system, then the quality of the concrete can be guaranteed, the soil bearing capacity is not only obtained from the tip of the pile. Foundation planning needs to be well planned to support user safety and comfort. Pile foundation is one type of foundation chosen because it is more cost-effective and quality than other foundations. This study aims to plan the pile foundation for a new building at Baptist Hospital Kediri. The calculations carried out include calculating the load received by each column, the carrying capacity of a single pile permit, the dimensions and depth of the pile, as well as the required pile cap dimensions. Calculation of the pile foundation is carried out using the Mayerhoff method. The calculation results show that the load on the column area (K13) is 212.23.04 tons, the carrying capacity of the single pile permit (Qall) is 87509.33 kg and Quult is 218773.3 kg and the use of 4 piles on one pile with dimensions of 40 x 40 cm with a depth of 10.6 m, With these results can be used as a reference in the construction of a new building Baptist Hospital that is safe and able to withstand the load of the building.

International audience; The failure envelopes have been increasingly employed to evaluate the bearing capacity of foundation systems under both static and dynamic loads. Particularly, the aim of this study is to compute the ultimate bearing capacity of a rigid vertical pile group foundation systems subjected to a planar loading horizontal (H) and bending moment (M) in homogeneous purely cohesive soil. Accurate upper and lower bounds to the limit loads are calculated using finite element methods in combination with limit analyses theory via a novel numerical limit analysis code (OptumG3). The effects of key parameters such as pile length-to-diameter ratio (L/D), group spacing (S/D) and the group size as well. The resulting failure envelopes are presented in normalized form with an error ranging from ±1% to ±5%. The numerical results are compared and validated against several experimental results for rigid pile groups in cohesive soil. Finally, an empirical equation is proposed for the safe load domain and fitted to the numerical results. © 2019 Associazione Geotecnica Italiana, Rome, Italy.

Несмотря на развитие методов и технологий проектирования свайных фундаментов, этот процесс все еще заключает в себе определенные трудности. К ним относятся различные погрешности и неточности применяемых формул и используемого оборудования, возникающие из-за огромного разнообразия геологических условий. В данной статье рассмотрен процесс проектирования свайного фундамента в условиях Санкт-Петербурга и предложено дальнейшее проектное решение для анализируемого здания. Выводы, приведенный в этой работе, могут помочь проектировщикам, работающим в данном районе, более качественно и профессионально выполнить расчет здания с точки зрения фундамента., Despite the development of methods and technologies in design of pile foundations, this process still involves certain difficulties. They are the various errors and inaccuracies of the applied formulas and the used equipment arising because of a huge variety of geological conditions. In this article I have considered the design process of the pile foundation in the conditions of St.Petersburg and proposed a further design solution for the analyzed building. The conclusions made on the basis of this work can help the designers in this area to carry out the calculation of the building in terms of the foundation more efficiently and professionally.

The Thies-Touba toll highway is one of the largest road projects in West Africa. It is 115 km long and is made of 2 × 2 lanes for a speed limit of 130 km / h. Indeed, the geotechnical studies carried out, in order to characterize the ground foundations of the route and the major civil engineering structure, revealed the presence of karsts (cavities of dissolution in the marno-calcareous formations) under certain overpasses of the highway. The modelling of piles in the presence of karsts has shown that these cavities influence the stability of projected crossing structures. Thus, a solution of cavity treatment by drilling, followed by an injection of cement grout was proposed and carried out up to 29 m of depth compared to the natural ground in order to fill all the voids (fractures and holes). To control the effectiveness of cavity filling at depth, 29 m test cores were taken at the axis of the pile location. They showed that the filling of cavities was well done and gives a good bearing capacity of the soil.

The impact of installation methods on pile axial capacity is studied using centrifuge model testing. Compression and tension tests are carried out on model piles jacked at 1g or at 100g in dense Fontainebleau NE34 sand. The pile total compression capacity and shaft and tip resistance are analysed and compared with the current design standards used in offshore engineering. These results show that the axial capacity of the tested piles is clearly underestimated. Pile total tension capacities are also studied. A significant increase in tension capacity is observed in cyclically jacked piles unlike piles monotonically jacked at 100g.

International audience; This paper focuses on the establishment of a model factor for the calculation of the ultimate limit state (ULS) bearing capacity of piles in compression from Ménard pressuremeter tests results. First, the requirements of Eurocode 7 are presented: calculation methods used for pile foundations must be validated against the results of static load tests and a model factor can be introduced to reach a target safety. This model factor is meant to take into account the scatter of the calculation model, whereas the spatial variability of the ground properties is dealt with by means of statistical methods. Then an analysis of a database of 174 full-scale static pile load tests carried out by the Laboratoire Central des Ponts et Chausées (LCPC, now called IFSTTAR), over the last 40 years, mainly in France, is performed and a new calculation model is established based on pressuremeter test results. Finally, the calibration procedure for deriving the model factor used in the recent French standard for pile design following Eurocode 7 is explained using two approaches: one compares the dispersions of the former and new calculation models and the other performs statistical analysis combining the scatter of the calculation model and the spatial variability of ground properties. This model factor is introduced into the recent French standard for pile design following Eurocode 7.

Analytical equations were derived to determine the undrained lateral bearing capacity of rigid piles in cohesive soil. Piles in level ground and piles placed at a distance from the crest of a slope were examined, taking account of the effect of the adhesion at the pile–soil interface. The derived analytical solutions were used to develop charts relating the lateral pile capacity to the pile length/diameter ratio, the pile–soil adhesion, the distance of the point of load application from the ground to the pile diameter ratio, the inclination of the slope and the distance of the pile from the crest of the slope to the pile diameter ratio. They were also used to derive a reduction factor which, when multiplied by the lateral bearing capacity for level ground, gives the bearing capacity of the same pile near a slope. In addition, a critical non-dimensional distance between the pile and the crest of the slope, at which the bearing capacity approaches that for a level ground, was determined. The bearing capacity charts obtained for level ground were compared to the classic Broms' charts and to others derived using several different lateral earth pressure distributions along the pile. Comparisons were also made between the results of the proposed method for piles near slopes and those obtained from charts based on upper bound calculations. Finally, the proposed new method was validated through a comparison with the results of a large number of pile load tests, in which a remarkable agreement was observed between the analytical results and the measurements.

Centrifiige experiments were carried out to gain insight into the factors that affect the mobilized resistance during rapid load testing on piles in sand. The influence of generated pore water pressure during rapid load tests is shidied, and its effect on the commonly used unloadmg point method to derive the staticpile capacity. This paper describes the testing program and the test set-up. Typical measurement results from 36 rapid- and 12 static load tests are presented. The effects of the loading rate and excess pore pressures on the pile resistance are shown. The tests confirm that a rapid load test can overestimate the static capacity due to pore water pressure, for piles in medium to fme sands. The results of the pore pressure measurements show a combination of positive and negative excess pore pressure in the zone around the pile base, which can be explained by compression, volumetric behavior durmg shearmg and pore fluid flow around the pile.

International audience; Pile design is not only based on the assessment of bearing capacity, but can involve settlement calculations when the structures supported by piles need high service requirements. In this context, the load transfer approach with t–z curve models is one of the calculation methods used. The main issue for this method is the choice and implementation of the t–z curve modelling the behaviour of the soil around the pile and accounting for the progressive shaft friction mobilisation. In this paper, three types of t–z curve models from pressuremeter test results are compared: one proposed previously by R. Frank and S. R. Zhao in 1982 and two others presented here. The stiffness of each model is studied and a comparison is performed by considering 90 full-scale static load tests extracted from the IFSTTAR pile database. Measured and calculated values of the pile head displacement are compared for several loading levels considering different soil and pile types. For the three t–z curve models, the ratio of the measured pile head settlement value to the calculated one is analysed and the scatter of each t–z curve model is studied. Some considerations regarding the safety of the pile settlement calculations are proposed.

Changes in temperature in clays of low permeability typically induce excess porewater pressures. In the context of geothermal piles this effect has typically been overlooked since most installations have occurred in soils with higher values of permeability. A parametric study is presented that solves the governing differential equations one dimensionally in a pile to study the influence of the various parameters: temperature of the fluid, permeability and soil compressibility. A new shaft resistance reduction ratio has been also defined to illustrate the loss of bearing capacity. The study shows that when the value of permeability is 1E-11 m/s or lower, combined with a soil compressibility in excess of 20,000 MPa, the developed excess porewater pressures can potentially reduce the effective stress locally to very low values. The solution applied to the case of the Lambeth College, London, also provides a plausible explanation to the observed loss of shaft friction of the tested pile.

Construction sites consisting of soft soils may require ground improvement to prevent excessive settlements or bearing capacity type failures and shear movements, which results in construction delays and premature failures. Among the various ground improvement techniques, the Geosynthetic Reinforced Piled Embankment Systems (GRPES) provide a practical and efficient solution due to the low cost and short construction times. Most of the piled embankments are constructed on end bearing piles. At large depths of foundation soil, floating piles are more economical and technically feasible than the end bearing piles. The design of floating piles involves complex soil-structure interaction and there are no clear uniform guidelines available for the design of embankments supported on floating piles. This paper presents the results of numerical investigation into the performance of geosynthetic reinforced embankments supported on end bearing as well as floating piles considering the pile-soil and geosynthetic-soil interaction. 3-D Column models are employed to carry out the parametric studies on factors such as the development of arching, skin friction distribution along the pile length and axial force distribution. Full three-dimensional analyses are carried out to study the overall behavior of the GRPES system and the results obtained from the analyses were compared with those from British Standard BS8006-2010. The results indicated that the use of floating piles could considerably reduce the settlements and the embankment load transferred through the piles to the foundation soil is found to depend very much on the length of the piles. This aspect needs to be accounted for while calculating the arching factor in the empirical equations. � 2015 Elsevier Ltd.

Tapered piles represent a more equitable distribution of the pile material in several respects. In order to study their efficiency over piles of uniform section with the same material input, a three-dimensional finite element analysis is developed. The numerical procedure accounts for the non-linear elastic behaviour of both the soil and the pile-soil interface. In order to include the latter, which involves relative slip and debonding, zero/non-zero thickness interface elements are used. Three shapes of cross-section, viz. circular, square and triangular, have been attempted for the piles. The load-settlement behaviour under axial load predicted by the analysis is compared with laboratory test results obtained on instrumented model piles, installed as 'replacement' piles, and the fit obtained is found to be reasonably good. Also examined are interface shear and axial force in the pile, displacement and stress fields in the medium and the progression of failure in the latter.

Centrifiige experiments were carried out to gain insight into the factors that affect the mobilized resistance during rapid load testing on piles in sand. The influence of generated pore water pressure during rapid load tests is shidied, and its effect on the commonly used unloadmg point method to derive the staticpile capacity. This paper describes the testing program and the test set-up. Typical measurement results from 36 rapid- and 12 static load tests are presented. The effects of the loading rate and excess pore pressures on the pile resistance are shown. The tests confirm that a rapid load test can overestimate the static capacity due to pore water pressure, for piles in medium to fme sands. The results of the pore pressure measurements show a combination of positive and negative excess pore pressure in the zone around the pile base, which can be explained by compression, volumetric behavior durmg shearmg and pore fluid flow around the pile.

Les changements intervenus depuis l’epoque de la prenorme ENV 1997-1 et la necessite actuelle d’etalonner les raccordements nationaux a l’Eurocode 7 (norme EN 1997-1), justifient la mise au point de methodes operationnelles de comparaison des niveaux de securite et de calage des coefficients partiels. Pour le dimensionnement des pieux sous charges axiales de compression vis-a-vis de l’etat limite de defaut de capacite portante, on met en evidence que les niveaux globaux de securite recommandes par la norme europeenne EN 1997-1 et par le reglement officiel francais « Fascicule n° 62 – Titre V » presentent des ordres de grandeur comparables. Un calage par ajustement est tout d’abord propose et permet de deboucher sur une evaluation du coefficient de modele de resistance γRd qui, utilise conjointement avec les valeurs des coefficients partiels recommandees pour l’approche 2 de l’EN 1997-1, permet de retrouver les niveaux de securite du Fascicule 62-V. Pour le calcul a partir des resultats des essais de sol, un calage probabiliste des coefficients partiels de resistance est egalement mis en œuvre a l’aide d’une serie d’essais de pieux ; on ouvre un debat sur les niveaux de securite a prendre en compte dans la combinaison fondamentale : la methode des « valeurs de calcul » de l’annexe C de l’Eurocode : Bases du calcul des structures (norme EN 1990) donnerait des resultats trop securitaires au regard de la pratique ; on met en œuvre une « methode inverse » qui remonte a une probabilite cible de ruine sous-jacente, en reference aux coefficients partiels proposes par les codes de calcul etudies. Les resultats des calages des coefficients partiels sont des intervalles du fait des diverses interpretations envisageables de la valeur caracteristique des proprietes des sols. Ces resultats pourront etre reexamines pour tenir compte de nouvelles comparaisons realisees entre le modele pressiometrique (ou un autre modele a partir d’essais de sol) et les essais de chargement statique de pieux.

m ÖZET Bir temel kazığının nihai taşıma kapasitesi bir çok yaklaşımla bulunabilmektedir. Standart Penetrasyon Deneyi, Wıir çevresinde ve dünyada yaygın olarak kullanılan bir zemin araştırma yöntemidir. Bu deney ile, kazığın taşıma gücü hesabında yararlanılan, zeminin direnç profili elde edilmektedir. Bu tez çalışmasında, tekil bir kazığın eksenel nihai taşıma gücü hesabım Standard Penetrasyon Direnci profiline dayanarak yapma imkanı sağlayan bir bilgisayar programı hazırlanmıştır. Programlama dili olarak Visual Basic 5.0 kullamlmıştır. Programda, zemin katmanları bir çok alt tabakaya ayrılarak detaylı analiz yapılabilmektedir. Program, sonuçlan ve grafikleri bir yazıcıdan verecek şekilde oluşturulmuştur. Programın sağlıklı çalıştığını gösterebilmek için îzmir Körfezi çevresinde yer alan 8 ayrı lokasyona ait 32 adet sondaj kuyusu verisi programa girilerek, sonuçları alınmış, yöresel, geçici bir kazık taşıma kapasitesi modeli yan ürün olarak elde edilmiştir. Program tekil bir temel kazığının nihai taşıma kapasitesinin ayrıntılı ve hızlı bir şekilde hesaplanmasını sağlamaktadır. Yeterli penetrasyon direnci verisi olması halinde, bir bölge için kazık taşıma kapasitesi modellemesi hızlı bir şekilde oluşturulabilmektedir. n ABSTRACT The ultimate bearing capacity of a foundation pile can be estimated by several different approaches. Standard Penetration Test being the most frequently used soil investigation technique in Izmir region and all over the World, provides a resistance profile for the estimation of single pile bearing capacity. In this thesis, a computer program for the analysis of the ultimate axial load bearing capacity of a single pile based on the Standard Penetration Resistance (SPT- N) profile has been prepared in Visual Basic 5.0 programming language. In the program, the soil layers has been divided into sub layers in order to obtain detailed results. The program has been written so that the results and resulting graphs can be sent to a printer. In order to test the program, runs with the data of thirty-two boring logs from eight different locations surrounding the Izmir Bay has been performed, and a tentative regional modeling of ultimate bearing capacity has been obtained. Computer Program provides the calculation of the ultimate axial bearing capacity of a single pile in a short time. Thus, a regional modeling can be formed very quickly, if there is enough penetration resistance data vcrtKfacacwrtMKumuui B0K0MANTASYON MEBKIZl 128

ÖZET Kazıklı temeller esas olarak, güvenli ve ekonomik bir yüzeysel temel teşkilinin olanaklı olmadığı hallerde tercih edilen bir derin temel çeşididir. Kazıldı temel sistemi düşünülürken, temel zemini özelliklerinin öncelikle bilinmesi ve diğer alternatiflerin de yeteri kadar incelenmiş olması gerekmektedir. Gelişen teknoloji ile artan kazık imal olanakları sonucu; kazıklar, uygulamada yaygın olarak kullanılmaktadırlar. Kazıklı temellerin projelerndirilmesinde ilk karşılaşılan sorun, belirlenen zemin profili için bir kazığın emniyetle taşıyabileceği yükün bulunmasıdır. Kazık servis yükünün belirlenmesinde, zemin mekaniği ilkeleri uygulamasının büyük önemi olmakla beraber tecrübeye dayalı pratik bilgilerden de faydalanılmahdır. Kazıkların taşıma gücünün bulunmasında en güvenilir yol olan yükleme deneyleri, statik ve dinamik formüllere göre daha gerçekçi sonuçlar verirler. Kazık yükleme deneyinin amacı, kazığın nihai taşıma yükünü belirlemenin yanında, kazığın statik ve dinamik formüllerle bulunan servis yükünü taşıyıp taşıyamayacağım kontrol etmektir. Gerekli olan bütün bilgiler, kazığın yük-oturma diyagramından elde edilir. Eksenel yüklü kazıkların düşey taşıma kapasitesini konu alan bu çalışmada öncelikle 1. ve 2. Bölümde kazıklar hakkında teorik bilgiler verilmeye çalışılmış ve kazık tipi seçimini etkileyen faktörler incelenmiştir. Daha sonra 3. Bölümde statik yöntemler ile kazık taşıma gücü hesabı hakkında bilgiler verilerek kullanılan yöntemler kohezyonhı ve kohezyonsuz zeminler için ayrı ayrı incelenmiştir. 4. Bölümde ise kazıkların taşıma kapasitelerinin hesaplanmasında önemli rol oynayan kazık yükleme deneylerinden bahsedilmiştir. 5. Bölümde ise deneysel çalışmalara yer verilmiş olup laboratuvarda eksenel yükleme altındaki model kazığın taşıma kapasitesi ve oturma değerleri hakkında bilgiler verilmiştir. Ayrıca bu bölümde model kazığa ait laboratuvar deneylerinden elde edilen sonuçların, ampirik formüllerden hesaplanan değerler ile teorik karşılaştınlmasına yer verilmiştir. Anahtar Kelimeler: Kazık, temel, eksenel yük, taşıma kapasitesi, oturma. vm ABSTRACT Pile foundations are the deep foundations to transfer superstructure through weak compressible soil strata to suffer or more compact soil or onto rocks. In the design of pile foundations, the main question is to evaluate the ultimate bearing capacity of a single pile for a given soil profile and pile type In slightly cohesive or non - cohesive soils it is difficult to recover undisturbed samples and to conduct laboratory tests on these samples for determining the strength and deformation properties of the soils. The recommended correlations between the bearing capacity of axially loaded piles and the field tests such as SPT, CPT and MPT. The accurate determination of pile bearing capacity is very important in the design of a piled foundation system in order to obtain a safe and economic structure. The estimation of a pile load capacity and settlement under a load is based on the results of field investigations, laboratory testing and empirical and semi empirical methods. These estimated values should then be confirmed by field pile load tests. It is possible to obtain information about the future behaviour of the project piles by performing load tests. Load test is a preferred system to determine the bearing capacity of various type of piles in all kinds of soil. When the penetration rate is kept constant during a load test (the CRP method) the corresponding force is measured. The constant-rate-of-penetration method (CRP) is the reverse to the (ML) method. In the (CPR) test, the pile head is forced to settle at a predetermined rate, normally 0.02 in. / min. (0.5 mm/min) and the force that is required to achieve the penetration is recorded. The test is carried out to a total penetration of 2 in. or in. 3 in (50 mm. or 73 mm.) or to the maximum capacity of the reaction arrangement, which means that the test is completed within about 2 hr. - 3 hr. The CRP method has the advantage that a load test can be carried out rapidly and that the ultimate load for friction piles in cohesive soils is in general well defined. But it is not possible to get some information of the magnitude of the creep with the CRP method. The CPR test will provide some important information, when carried to failure from the shape of the load-movement curve, the behavior of the pile as an end-bearing, a friction-pile in sand with more or less end-bearing resistance, or a friction-pile in clay can be evaluated. Keywords: Pile, foundation, bearing capacity, axial load, settlement. K 131

The bearing capacity of piles consists of both base resistance and side resistance. The side resistance of piles is in most cases fully mobilized well before the maximum base resistance is reached. As the side resistance is mobilized early in the loading process, the determination of pile base resistance is a key element of pile design. Static cone penetration is well related to the pile loading process, since it is performed quasi-statically and resembles a scaled-down pile load test. In order to take advantage of the CPT for pile design, load-settlement curves of axially loaded piles bearing in sand were developed in terms of normalized base resistance (qb/qc) versus relative settlement (s/B). Although the limit state design concept for pile design has been used mostly with respect to either s/B = 5% or s/B = 10%, the normalized load-settlement curves obtained in this study allow determination of pile base resistance at any relative settlement level within the 0 – 20% range. The normalized base resistance for both non-displacement and displacement piles were addressed. In order to obtain the pile base load-settlement relationship, a 3-D non-linear elastic-plastic constitutive model was used in finite element analyses. The 3-D non-linear elastic-plastic constitutive model takes advantage of the intrinsic and state soil variables that can be uniquely determined for a given soil type and condition. A series of calibration chamber tests were modeled and analyzed using the finite element approach with the 3-D non-linear elastic-plastic stress-strain model. The predicted load-settlement curves showed good agreement with measured load-settlement curves. Calibration chamber size effects were also investigated for different relative densities and boundary conditions using the finite element analysis. The value of the normalized base resistance qb/qc was not a constant, varying as a function of the relative density, the confining stress, and the coefficient of lateral earth pressure at rest. The effect of relative density on the normalized base resistance qb/qc was most significant, while that of the confining stress at the pile base level was small. At higher relative densities, the value of qb/qc was smaller (qb/qc = 0.12 -0.13 for DR = 90%) than at lower relative densities (qb/qc = 0.19 - 0.2 for DR = 30%). The values of the normalized base resistance qb/qc for displacement piles are higher than those for nondisplacement piles, being typically in the 0.15 - 0.25 range for s/B = 5% and in the 0.22 - 0.35 range for s/B = 10%. The values of the normalized base resistance qb/qc for silty sands are in the 0.12 – 0.17 range, depending on the relative density and the confining stress at the pile base level. The confining stress is another important factor that influences the value of qb/qc for silty sands. For lower relative density, the value of qb/qc decreases as the pile length increases while that for higher relative density increases. For effective use of CPT-based pile design methods in practice, the method proposed in this study and some other existing methods reviewed in this study were coded in a FORTRAN DLL with a window-based interface. This program can be used in practice to estimate pile load capacity for a variety of...

Kazıklar, temel yüklerini düşük taşıma kapasiteli toprak katmanlarından daha derinlerdeki yüksek taşıma kapasiteli toprak yada kaya katmanlarına nakletmek için kullanılan uzun ve narin elemanlardır. Normal zemin koşullarında şiddetli kaldırma kuvvetlerine ve zayıf zemin koşullarında yatay yüklere karşı direnç gösterir. Bu çalışmada, düşey yük altındaki bir kazığın taşıma kapasitesi yükleme deneyleri ile incelenmiştir. Özellikle amaç, UNTTEST adı ile anılan hazır paket programın kazığın taşıma kapasitesini tahmin etmedeki geçerliliğini araştırmaktır. PILEAX programı, düşey yüklü kazıklarda yük-oturma eğrilerini bu kazıkların yük transferi-hareket eğrileri yardımı ile hesaplamak için geliştirilmiştir. Geliştirilen bu programdan elde edilen sonuçların sınırlı bir bölümü, hazır paket programda veri olarak kullanılarak paket programda tarif edilen metodların düşey yüklü kazıkların taşıma kapasitesini tahminindeki başarısı incelenmiştir. Piles are relatively long and slender members used to transmit foundation loads through soil strata of low bearing capacity to deeper soil or rock strata having a high bearing capacity. They are also used in normal ground conditions to resist heavy uplift forces or in poor soil conditions to resist horizontal loads. The ultimate bearing capacity of an axially loaded pile under load tests is investigated in this study. Specifically, the aim is to investigate the effectiveness of a software named UNITEST, of predicting the ultimate bearing capacity of a pile. A program is developed named as PILEAX to compute load-settlement curves of axially loaded piles by using load transfer-movement (t-z) curves of the piles. The limited portion of the obtained data from the developed computer program is used as input data for the software to determine the success of the methods described in the software of predicting the ultimate bearing capacity of the axially loaded pile. 191

ÖZET Kazıklı temeller, yüzeysel temel sistemlerinin güvenli ve ekonomik olmadığı durumlarda tercih edilirler. Yüklerin sağlam zemin tabakalarına aktarılması bakımından en uygun temellerdir. Kazıkları çeşitli malzemeden, değişik biçimlerde imal etmek mümkündür. Gelişen teknoloji ile artan kazık imal yöntemleri, zemin sarflarına bağlı olarak düşünülmelidir. Bu çalışmada, kazıklı temeller sınıflandırılarak her tür kazığın özellikleri ve davranışları kısaca incelenip, özellikle yerinde dökme kazıklar üzerinde durulmuştur. Altı bölümden oluşan bu tez çalışmasında, yerinde dökme kazıklı temeller hakkında yeterli bilgilerin verildiği sanılmaktadır. Birinci bölümde, temeller hakkında kısa ve genel açıklamalarda bulunulmuş, yüzeysel ve derin temellerin tanımlan yapılmıştır. ikinci bölümde, kazıklı temeller anlatılmıştır. Kazıklı temel çeşitleri açıklanarak, her bir kazık türünün avantaj ve dezavantajları verilmiştir. Ayrıca kazık tipi seçimini etkileyen faktörler hakkında kısa bilgiler sunulmuştur. Öçüncü bölümde, yerinde dökme kazıklı temeller incelenmiştir. Yerinde dökme kazıklı temel türleri detaylı olarak anlatılmış, her birinin avantaj ve dezavantajları verilmiştir. Dördüncü bölümde, yerinde dökme kazıklı temellerin taşıma güçlerine ait yöntemler incelenmiştir. Taşıma güçlerine ait çeşitli yöntemler değerlendirilip, kazık yükleme deneyleri detaylı olarak açıklanmıştır. Kazık yükleme deney sonuçlanndaki farklı yorumlama metotları da belirtilerek, yerinde dökme kazıklar için en uygun olanları belirlenmeye çalışılmıştır. Ayrıca bu bölümde, yükleme deneyleri ile ilgili çeşitli ülke ve kuruluşların, kural ve standartları verilmiştir. Beşinci bölümde ise alt değişik yükleme deneyi sonuçlan incelenmiş ve değerlendirilmiştir. Altıncı ve son bölümde, bu çalışmadan elde edilen sonuçlar açıklanarak, verilen öneriler sunulmuştur. SUMMARY EVALUATIONS ON BEARING CAPACITY OF CAST- IN - PLACE PILES BY LOADING TESTS Pile foundations are preferred in such cases when the shallow foundation systems are not safe and economical. These foundations proper for transferring the surface loads to lower levels in the soil mass. Piles can be prepared from different materials and in different methods. Preparing methods that are increasing in number by developing technology, must be considered according to soil conditions. In this study, pile foundations are classified with respect to their properties, and than responses of the each piles are reviewed, briefly. Of the foundations, cast in - place piles are investigated in details. Six different loading test related with the cast in - place piles are applied, then the ultimate bearing and service bearing capacities of the each piles are determined. In the first chapter, short and general information about pile foundations are presented. Shallow and deep foundations are defined and classified. Shallow foundations are consist of single, continuous and radial foundations while deep foundations are consist of pile foundations and piers. Most commonly used type of deep foundations are pile foundations. In the second chapter, pile foundations are discussed. Pile foundations can be classified in to the following their materials; 1. Timber piles 2. Steel piles 3. Concrete piles 4. Composite piles. All piles are discussed, briefly and some information about their responses are given. Advantages and disadvantages of these piles are given here. According to type of transferring the loads, pile foundations are also classified as follows; 1. End bearing piles 2. Friction or floating piles 3. Tensile piles 4. Anchor piles 5. Compaction piles 6. Slant piles The factors affecting the selection of pile type are also given.In the third chapter, cast in - place piles are studied. These piles, which are the main topics of this thesis are investigated in detail and classified as shown below; a. Cast in - place driven piles 1. Cased cast in - place driven piles 2. Uncased cast in - place driven piles b. Cast in - Place bored piles 1. Cased cast in -place bored piles 2. Uncased cast in - place bored piles Above mentioned pile types are explained and their preparing methods together with the advantages and disadvantages are given. In the fourth chapter, methods concerned with bearing capacities of cast in - place piles are studied and can be given as; 1. Static formulas 2. Penetration of in - situ tests a. SPT (Standard Penetration Test) b. CPT (Cone Penetration Test) c. MPT ( Menard Penetration Test) 3. Pile loading test. In the calculation of bearing capacity by using Static formulas, Ultimate load bearing capacity of pile (Qd) is consist of two main components. One of the components is end - bearing capacity (Qp), the other one is surface resistance (Qs). Ultimate bearing capacity of piles can be written as; Qd = QP +Qs =qp*Ap +qs*As(1) Where; Ap: Area of pile end As : Area of surface of pile qp : Unit bearing capacity of soil that is on the end of pile qs : Average unit surface friction (resistance) In the computation of qp and qs, there are same difference according to soil type and scientist's methods. In pile bearing capacity calculation by using SPT test unit end - bearing capacity for driven piles are given approximately, below; In the sandy soils; xuqp = 0.4 * N (mpa) =4 * N (kg/cm2)(2) In gravel soils; qp = 0.6 * N (mpa) = 6 * N (kg/cm2)(3) for the silt soils; qp = 0.25 * N (mpa) = 2.5 * N (kg/cm2)(4) Where, N : The value of SPT strike of the soil, in the level of pile end. Average unit surface bearing capacity in sandy soils can be calculated by using below equations; for driven piles, qs = 0.002 * N- (mpa) =0.02 * N- (kg/cm2)(5) for bored piles, qs = 0.006 * N- (mpa) = 0.06 * N- (kg/cm2)(6) Where, N- : The average value of SPT strike of the soil, in the levels of pile surfaces. It is advised to use unit surface bearing capacity not grater than 1 kg/cm2 for driven piles and 0.4 for bored piles. In pile bearing capacity calculation by using CPT test, for unit end - bearing capacity; Qp = qo:(7) for average unit surface bearing capacity; xiiiqs = a * fo(8) q8 = 0.0009 * qc (mpa) = 0.009 * cjc (kg/crtf)(9) equations are given. Where, qc : Cone end resistance fc : Cone friction resistance a : coefficient In pile bearing capacity calculation by using MPT test for unit end - bearing capacity; qp = qo + k * (P1-P0)(10) qp* = k * Pi*(1 1) for average unit bearing capacity; qs = Pi*/30+30 (kpa) = P,V 3000 +0.3 (kg/cm2)(12) relation is given. Pile loading test method are explained as the last method. Pile loading test systems and purposes are discussed. There are four different method for test procedure, as shown below, a. Slow maintained load test (SM), b. Quick maintained load test (QM), c. Constant rate of penetration test (CRP), d. Sweden cyclic load test (SC). At the end of pile loading test, load - movement curve, load - plastic movement curve and load - elastic and plastic movement curve are drawn, then evaluations are done for ultimate loading capacity. There are different methods for determining ultimate and service load in load - movement curves. These methods are; 1. Davisson method 2. Chin method 3. De Beer method 4. Brinch Hansen 90% criteria X1V5. Brinch Hansen 80% criteria 6. Mazurkiewicz method 7. Fuller and Hoy method 8. Butler and Hoy method 9. Van der Veen method 10. German standard 11. U.SA standard Each method are investigated and, the type of determining ultimate and service loads are explained. Also, standards of some country's and some corporations 's about determination of pile bearing capacity. In the fifth chapter, the result of six different pile loading test are discussed. Load - movement load - elastic and plastic movement and movement - time curves of each loading test are drawn. These curves are interpreted according to the methods which are mentioned in chapter 4 and, ultimate and service load are calculated for each pile proper methods for cast in - place piles are determined. In the sixth chapter, the results, which are obtained by this study, and recommendations are presented. The points which to be care of while making the loading test are explained. The problems that may come out and counter measures for these problems are presented. The main purpose of the pile loading test is to the determine the maximum load that pile can carry. But in our country, generally, it is used for controlling the service load. So, this shown us, the purpose of pile loading test is miss understand in Turkey. As a result, the safest method as to determine pile loading capacity, is pile loading tests. For the cast in - place piles, the best suitable procedure is slow maintained loading method. In the interpretation of the test result, for these type of piles, methods are summarized as shown table below. Table 1 XVDIN, ASTM, De Beer, Fuller and Hoy, meüıods are suitable for cast in - place piles. Butler and Hoy method is conservative in the ratio 5% - 18%. Chin method give larger values about 1 25% - 300%. Other methods are not used for cast in - place piles. XVI 140

Mooring dolphins are generally supported on group of piles and these piles are subjected to significant lateral loads due to mooring pull of the berthing vessel and wind and wave action. In this investigation, the behaviour of pile groups under lateral load has been studied by conducting static load tests on instrumented model pile groups embedded in clayey soil, changing the spacing between piles, number of piles and the arrangement of piles in the group. The results indicated that the capacity of a pile group depends not only on the spacing of piles in the group but also on the arrangement of piles with reference to the direction of loading. For cyclic load application, the deflections are observed to stabilize after some cycles depending on the cyclic load level. The post cyclic behaviour of the piles has been explained in terms of the changes in the soil strength behaviour during cyclic loading.

The effect of a small alternating load superimposed on a static load on the displacement rate of piles in a frozen sand and a frozen natural soil has been studied at -2.2 degrees C. An alternating stress as small as 3 per cent of the static stress caused an increase in rate of displacement in the region where the displacement rate was decreasing with time, and doubled the steady-state displacement rate of both wood and concrete piles. Under dynamic loads the design life of pile foundations calculated on the basis of allowable settlement will be reduced or, alternatively, the bearing capacity of piles for dynamic loads will be smaller than the bearing capacity for static loads., Fourth Canadian Permafrost Conference, March 2, 1981