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I samband med Förbifart Stockholm och Tvärförbindelse Södertörn förväntas en flaskhals skapas vid Vårbybron i södra Stockholm. För att förhindra överbelastning planeras en nybyggnation där pålgrundläggning med grävpålar föreslås. Markförhållanden är ovanliga i Stockholm, med över 100 meter ned till berg. Komplexa omständigheter i området gör det nödvändigt att analysera markrörelser som verkar på grundläggningen. Syftet med studien är att undersöka horisontella- och vertikala sättningar vid ett brolandfäste. Syftet är vidare att analysera vilken typ av numerisk konstitutiv modell som är lämplig med hänsyn till studiens specifika fall och område; Mohr-Coulomb (MC), Hardening Soil (HS) och Hardening Soil med small-strain stiffness (HSS). Slutligen ska jordparametrarnas väsentlighet avgöras i en parameterstudie. Sonderingsdata tillämpas i studien för att skapa en jordlagermodell i AutoCAD Civil 3D 2019 Metric och vidare simulering av sättningar i Plaxis 2D. Vid modellering av sättningar i förekommande geologi rekommenderas att en avancerad modell används, med fördel HSS. Däremot kräver mer avancerade modeller noggranna indata för tillförlitligt resultat och ytterligare tester för styvhetsparametrar bör utföras. I detta projekt kan dyrare tester tänkas sänka slutgiltig budget, eftersom underskattning av moduler i djupa och fast lagrade jordar baserade på konservativt valda moduler ger upphov till en dyrare konstruktion., In conjunction with the opening of the Stockholm Bypass and Tvärförbindelse Södertörn, a bottleneck is expected at the bridge Vårbybron in southern Stockholm. To prevent traffic congestion, a new construction is planned where pile foundation consisting of bored piles is proposed. The ground conditions are unusual and not typical for Stockholm involving over 100 meters distance to rock. Complex circumstances in the area makes it complicated as well as necessary to analyze ground movements. The aim of the study is to investigate horizontal- and vertical settlements at a bridge abutment. The aim is further to analyze which type of numerical constitutive model that is appropriate with respect to the specific case and area; Mohr-Coulomb (MC), Hardening Soil (HS) and Hardening Soil with small-strain stiffness (HSS). Finally, the significance of the soil parameters is to be determined in a parameter analysis. Results from soundings are used to create a geological model in AutoCAD Civil 3D 2019 Metric. Furthermore, simulation of settlements in Plaxis 2D is performed. It is recommended to apply advanced models for this type of geology, advantageously HSS. However, more advanced models require accurate input data to obtain reliable results, and additional tests for stiffness parameters must be performed for accuracy in the results. In this project, more expensive tests can be thought of as lowering the final budget, as underestimation of modules in deep and stiff soils based on conservatively selected modules leads to an unnecessarily expensive construction.

I samband med Förbifart Stockholm och Tvärförbindelse Södertörn förväntas en flaskhals skapas vid Vårbybron i södra Stockholm. För att förhindra överbelastning planeras en nybyggnation där pålgrundläggning med grävpålar föreslås. Markförhållanden är ovanliga i Stockholm, med över 100 meter ned till berg. Komplexa omständigheter i området gör det nödvändigt att analysera markrörelser som verkar på grundläggningen. Syftet med studien är att undersöka horisontella- och vertikala sättningar vid ett brolandfäste. Syftet är vidare att analysera vilken typ av numerisk konstitutiv modell som är lämplig med hänsyn till studiens specifika fall och område; Mohr-Coulomb (MC), Hardening Soil (HS) och Hardening Soil med small-strain stiffness (HSS). Slutligen ska jordparametrarnas väsentlighet avgöras i en parameterstudie. Sonderingsdata tillämpas i studien för att skapa en jordlagermodell i AutoCAD Civil 3D 2019 Metric och vidare simulering av sättningar i Plaxis 2D. Vid modellering av sättningar i förekommande geologi rekommenderas att en avancerad modell används, med fördel HSS. Däremot kräver mer avancerade modeller noggranna indata för tillförlitligt resultat och ytterligare tester för styvhetsparametrar bör utföras. I detta projekt kan dyrare tester tänkas sänka slutgiltig budget, eftersom underskattning av moduler i djupa och fast lagrade jordar baserade på konservativt valda moduler ger upphov till en dyrare konstruktion., In conjunction with the opening of the Stockholm Bypass and Tvärförbindelse Södertörn, a bottleneck is expected at the bridge Vårbybron in southern Stockholm. To prevent traffic congestion, a new construction is planned where pile foundation consisting of bored piles is proposed. The ground conditions are unusual and not typical for Stockholm involving over 100 meters distance to rock. Complex circumstances in the area makes it complicated as well as necessary to analyze ground movements. The aim of the study is to investigate horizontal- and vertical settlements at a bridge abutment. The aim is further to analyze which type of numerical constitutive model that is appropriate with respect to the specific case and area; Mohr-Coulomb (MC), Hardening Soil (HS) and Hardening Soil with small-strain stiffness (HSS). Finally, the significance of the soil parameters is to be determined in a parameter analysis. Results from soundings are used to create a geological model in AutoCAD Civil 3D 2019 Metric. Furthermore, simulation of settlements in Plaxis 2D is performed. It is recommended to apply advanced models for this type of geology, advantageously HSS. However, more advanced models require accurate input data to obtain reliable results, and additional tests for stiffness parameters must be performed for accuracy in the results. In this project, more expensive tests can be thought of as lowering the final budget, as underestimation of modules in deep and stiff soils based on conservatively selected modules leads to an unnecessarily expensive construction.

В статье представлена методика расчета несущей способности буронабивных свай из бетонов и растворов на напрягающем цементе при работе на вертикальную статическую нагрузку, сравнение результатов расчета по предлагаемой методике с экспериментальными данными и другими методами расчета буронабивных свай. Методика позволяет определить рекомендуемые границы расположения бетонов и растворов на напрягающем цементе в свае, напряжения и деформации грунта вдоль боковой поверхности и под нижним концом сваи, повышение несущей способности сваи.

This paper reports a field study on the downdrag and dragload of two pairs of bored piles installed in consolidating ground in the Zhejiang coastal area, China. During and after the construction of a 2.5-m-high embankment, the dragload and downdrag induced on the four piles, surface and subsurface soil settlement, pore water pressure, and lateral earth pressure were monitored. The field measurements show that the maximum dragloads in piles founded on relatively stiffer (end-bearing pile) and relatively softer layers (floating pile) ranged from 1,198 to 1,238 kN and from 798 to 870 kN, respectively. This suggests that the dragload in a floating pile can be one-third less than that in an end-bearing pile with similar geometries and embedded in the same consolidating ground. Deduced beta values above the neutral plane (NP) in the clay strata ranged from 0.28 to 0.3, respectively. A much smaller beta (0.04-0.06) was found below the NP. The existing analytical solutions overestimated the depth of the NP, leaving the structural design of the piles on the safe side. (C) 2015 American Society of Civil Engineers.

This paper reports a field study on the downdrag and dragload of two pairs of bored piles installed in consolidating ground in the Zhejiang coastal area, China. During and after the construction of a 2.5-m-high embankment, the dragload and downdrag induced on the four piles, surface and subsurface soil settlement, pore water pressure, and lateral earth pressure were monitored. The field measurements show that the maximum dragloads in piles founded on relatively stiffer (end-bearing pile) and relatively softer layers (floating pile) ranged from 1,198 to 1,238 kN and from 798 to 870 kN, respectively. This suggests that the dragload in a floating pile can be one-third less than that in an end-bearing pile with similar geometries and embedded in the same consolidating ground. Deduced beta values above the neutral plane (NP) in the clay strata ranged from 0.28 to 0.3, respectively. A much smaller beta (0.04-0.06) was found below the NP. The existing analytical solutions overestimated the depth of the NP, leaving the structural design of the piles on the safe side. (C) 2015 American Society of Civil Engineers.

For piling works in sensitive soil, especially in inner city projects, it is essential to be aware of the available methods and to choose the most suitable method to minimize the risk of damaging existing buildings or endanger the workers at the construction site. Down-the-hole drilling of piles is a relatively safe method and can be separated into drilling with air powered hammers and water powered hammers. This study compares water powered drilling with air powered drilling and shows that the impact on the soil generated by air powered drilling is larger than that from water powered drilling. A field study was carried out where 4 piles were drilled, two with air powered DTH drilling and two with water powered DTH drilling. The drilling was carried out in clay resting on an approximately 4 m layer of silt and friction soil. The total soil depth was about 12- 15 m. To analyze the soil influence, settlements were measured at ground level and in depth and pore pressure was measured in the middle of the clay layer. This study distinguished two major problems when drilling through this type of soil. The first is the risk of over-drilling in the friction layer. The second problem is the risk of increasing the pore pressure in the clay. Both these problems were experienced when using air powered drilling but for the water powered case only a small pore pressure increase and no over-drilling was observed. In conclusion, drilling with water has less influence on the soil in the sense that it gives a smaller effect on the pore water pressure and causes smaller settlements., För pålningsarbeten i känsliga jordar och speciellt i innerstadsprojekt är det viktigt att vara medveten om befintliga metoder och välja den mest gynnsamma av dessa för att på så sätt minimera de risker som är sammankopplade med arbetet. Sänkhammarborrning är en relativt säker påldrivningsmetod och kan delas upp i luftdriven borrning och vattendriven borrning. Det här arbetet jämför dessa två metoder och visar att formationspåverkan vid luftdriven borrning är större än den vid vattendriven borrning. Arbetet baseras på en fältstudie där totalt 4 pålar borrades, två med luftdriven borrning och två med vattendriven borrning. Borrningen genomfördes i en formation med lera ovanpå silt och ren friktionsjord och jorddjupet på platsen varierade mellan 12-15 meter. För att undersöka formationspåverkan mättes sättningar på djupet och på markytan och portryck mättes mitt i lerlagret. Arbetet kunde urskilja två huvudsakliga problem vid borrning i den här typen av formation. Det första är risken för överborrning i friktionslager och det andra är risken för portrycksökning i tätare lerlager. Båda dessa fenomen observerades när luftborrning utfördes men inget av dem kunde urskiljas då vattenborrning utfördes. Sammanfattningsvis kan sägas att vattendriven borrning påverkar jorden mindre i den mening att den ger upphov till mindre portrycksökning och orsakar mindre korttidssättningar.

This study emphasizes the effects of viscosity modifying agents (VMAs) on fresh and hardened properties of concrete. The properties of concrete were examined in terms of initial slump, bleeding, air content, setting time, compressive strength of concrete, and dewatering of mortar under high pressures. Additionally, the effect of surfactant type VMA on blending between concrete and bentonite fluid was also examined. Two different types of VMA, which are a surfactant type and a starch ether type with various dosages were used with or without water reducing admixtures in the tested mortar and concrete mixtures. From the experiments, it was found that the tested surfactant type VMA was not compatible with type D admixtures. The surfactant type VMA with type F admixtures increased the initial slump and air content, significantly reduced the bleeding, slightly reduced the compressive strength and had a negligible effect on setting time of the concrete. However, surfactant type VMA slightly increased the setting time of fly ash concrete. Furthermore, it effectively reduced blending between bentonite fluid and concrete. On the other hand, the use of starch in concrete mixtures slightly increased the air content, moderately reduced the bleeding, and slightly reduced the compressive strength of concrete. The increase of air by starch is less significant when compared to the case of surfactant type VMA. In the case of mortar test, the addition of surfactant type VMA slightly increased the mortar flow and v-funnel flow time due to enhancement of the air content and viscosity, respectively, of the mixtures, whereas starch ether decreased the mortar flow and increased the v-funnel time due to viscosity increase. By using dosages of surfactant type VMA equal to or higher than 3%, the pressurized dewatering of the mortars was significantly reduced. Furthermore, the use of surfactant type VMA in mortar mixtures with polycarboxylate based superplasticizer effectively reduced the pres

This paper reports a field study on the downdrag and dragload of two pairs of bored piles installed in consolidating ground in the Zhejiang coastal area, China. During and after the construction of a 2.5-m-high embankment, the dragload and downdrag induced on the four piles, surface and subsurface soil settlement, pore water pressure, and lateral earth pressure were monitored. The field measurements show that the maximum dragloads in piles founded on relatively stiffer (end-bearing pile) and relatively softer layers (floating pile) ranged from 1,198 to 1,238 kN and from 798 to 870 kN, respectively. This suggests that the dragload in a floating pile can be one-third less than that in an end-bearing pile with similar geometries and embedded in the same consolidating ground. Deduced beta values above the neutral plane (NP) in the clay strata ranged from 0.28 to 0.3, respectively. A much smaller beta (0.04-0.06) was found below the NP. The existing analytical solutions overestimated the depth of the NP, leaving the structural design of the piles on the safe side. (C) 2015 American Society of Civil Engineers.

This study emphasizes the effects of viscosity modifying agents (VMAs) on fresh and hardened properties of concrete. The properties of concrete were examined in terms of initial slump, bleeding, air content, setting time, compressive strength of concrete, and dewatering of mortar under high pressures. Additionally, the effect of surfactant type VMA on blending between concrete and bentonite fluid was also examined. Two different types of VMA, which are a surfactant type and a starch ether type with various dosages were used with or without water reducing admixtures in the tested mortar and concrete mixtures. From the experiments, it was found that the tested surfactant type VMA was not compatible with type D admixtures. The surfactant type VMA with type F admixtures increased the initial slump and air content, significantly reduced the bleeding, slightly reduced the compressive strength and had a negligible effect on setting time of the concrete. However, surfactant type VMA slightly increased the setting time of fly ash concrete. Furthermore, it effectively reduced blending between bentonite fluid and concrete. On the other hand, the use of starch in concrete mixtures slightly increased the air content, moderately reduced the bleeding, and slightly reduced the compressive strength of concrete. The increase of air by starch is less significant when compared to the case of surfactant type VMA. In the case of mortar test, the addition of surfactant type VMA slightly increased the mortar flow and v-funnel flow time due to enhancement of the air content and viscosity, respectively, of the mixtures, whereas starch ether decreased the mortar flow and increased the v-funnel time due to viscosity increase. By using dosages of surfactant type VMA equal to or higher than 3%, the pressurized dewatering of the mortars was significantly reduced. Furthermore, the use of surfactant type VMA in mortar mixtures with polycarboxylate based superplasticizer effectively reduced the pres

This study emphasizes the effects of viscosity modifying agents (VMAs) on fresh and hardened properties of concrete. The properties of concrete were examined in terms of initial slump, bleeding, air content, setting time, compressive strength of concrete, and dewatering of mortar under high pressures. Additionally, the effect of surfactant type VMA on blending between concrete and bentonite fluid was also examined. Two different types of VMA, which are a surfactant type and a starch ether type with various dosages were used with or without water reducing admixtures in the tested mortar and concrete mixtures. From the experiments, it was found that the tested surfactant type VMA was not compatible with type D admixtures. The surfactant type VMA with type F admixtures increased the initial slump and air content, significantly reduced the bleeding, slightly reduced the compressive strength and had a negligible effect on setting time of the concrete. However, surfactant type VMA slightly increased the setting time of fly ash concrete. Furthermore, it effectively reduced blending between bentonite fluid and concrete. On the other hand, the use of starch in concrete mixtures slightly increased the air content, moderately reduced the bleeding, and slightly reduced the compressive strength of concrete. The increase of air by starch is less significant when compared to the case of surfactant type VMA. In the case of mortar test, the addition of surfactant type VMA slightly increased the mortar flow and v-funnel flow time due to enhancement of the air content and viscosity, respectively, of the mixtures, whereas starch ether decreased the mortar flow and increased the v-funnel time due to viscosity increase. By using dosages of surfactant type VMA equal to or higher than 3%, the pressurized dewatering of the mortars was significantly reduced. Furthermore, the use of surfactant type VMA in mortar mixtures with polycarboxylate based superplasticizer effectively reduced the pres

For piling works in sensitive soil, especially in inner city projects, it is essential to be aware of the available methods and to choose the most suitable method to minimize the risk of damaging existing buildings or endanger the workers at the construction site. Down-the-hole drilling of piles is a relatively safe method and can be separated into drilling with air powered hammers and water powered hammers. This study compares water powered drilling with air powered drilling and shows that the impact on the soil generated by air powered drilling is larger than that from water powered drilling. A field study was carried out where 4 piles were drilled, two with air powered DTH drilling and two with water powered DTH drilling. The drilling was carried out in clay resting on an approximately 4 m layer of silt and friction soil. The total soil depth was about 12- 15 m. To analyze the soil influence, settlements were measured at ground level and in depth and pore pressure was measured in the middle of the clay layer. This study distinguished two major problems when drilling through this type of soil. The first is the risk of over-drilling in the friction layer. The second problem is the risk of increasing the pore pressure in the clay. Both these problems were experienced when using air powered drilling but for the water powered case only a small pore pressure increase and no over-drilling was observed. In conclusion, drilling with water has less influence on the soil in the sense that it gives a smaller effect on the pore water pressure and causes smaller settlements., För pålningsarbeten i känsliga jordar och speciellt i innerstadsprojekt är det viktigt att vara medveten om befintliga metoder och välja den mest gynnsamma av dessa för att på så sätt minimera de risker som är sammankopplade med arbetet. Sänkhammarborrning är en relativt säker påldrivningsmetod och kan delas upp i luftdriven borrning och vattendriven borrning. Det här arbetet jämför dessa två metoder och visar att formationspåverkan vid luftdriven borrning är större än den vid vattendriven borrning. Arbetet baseras på en fältstudie där totalt 4 pålar borrades, två med luftdriven borrning och två med vattendriven borrning. Borrningen genomfördes i en formation med lera ovanpå silt och ren friktionsjord och jorddjupet på platsen varierade mellan 12-15 meter. För att undersöka formationspåverkan mättes sättningar på djupet och på markytan och portryck mättes mitt i lerlagret. Arbetet kunde urskilja två huvudsakliga problem vid borrning i den här typen av formation. Det första är risken för överborrning i friktionslager och det andra är risken för portrycksökning i tätare lerlager. Båda dessa fenomen observerades när luftborrning utfördes men inget av dem kunde urskiljas då vattenborrning utfördes. Sammanfattningsvis kan sägas att vattendriven borrning påverkar jorden mindre i den mening att den ger upphov till mindre portrycksökning och orsakar mindre korttidssättningar.

This study emphasizes the effects of viscosity modifying agents (VMAs) on fresh and hardened properties of concrete. The properties of concrete were examined in terms of initial slump, bleeding, air content, setting time, compressive strength of concrete, and dewatering of mortar under high pressures. Additionally, the effect of surfactant type VMA on blending between concrete and bentonite fluid was also examined. Two different types of VMA, which are a surfactant type and a starch ether type with various dosages were used with or without water reducing admixtures in the tested mortar and concrete mixtures. From the experiments, it was found that the tested surfactant type VMA was not compatible with type D admixtures. The surfactant type VMA with type F admixtures increased the initial slump and air content, significantly reduced the bleeding, slightly reduced the compressive strength and had a negligible effect on setting time of the concrete. However, surfactant type VMA slightly increased the setting time of fly ash concrete. Furthermore, it effectively reduced blending between bentonite fluid and concrete. On the other hand, the use of starch in concrete mixtures slightly increased the air content, moderately reduced the bleeding, and slightly reduced the compressive strength of concrete. The increase of air by starch is less significant when compared to the case of surfactant type VMA. In the case of mortar test, the addition of surfactant type VMA slightly increased the mortar flow and v-funnel flow time due to enhancement of the air content and viscosity, respectively, of the mixtures, whereas starch ether decreased the mortar flow and increased the v-funnel time due to viscosity increase. By using dosages of surfactant type VMA equal to or higher than 3%, the pressurized dewatering of the mortars was significantly reduced. Furthermore, the use of surfactant type VMA in mortar mixtures with polycarboxylate based superplasticizer effectively reduced the pres

This study emphasizes the effects of viscosity modifying agents (VMAs) on fresh and hardened properties of concrete. The properties of concrete were examined in terms of initial slump, bleeding, air content, setting time, compressive strength of concrete, and dewatering of mortar under high pressures. Additionally, the effect of surfactant type VMA on blending between concrete and bentonite fluid was also examined. Two different types of VMA, which are a surfactant type and a starch ether type with various dosages were used with or without water reducing admixtures in the tested mortar and concrete mixtures. From the experiments, it was found that the tested surfactant type VMA was not compatible with type D admixtures. The surfactant type VMA with type F admixtures increased the initial slump and air content, significantly reduced the bleeding, slightly reduced the compressive strength and had a negligible effect on setting time of the concrete. However, surfactant type VMA slightly increased the setting time of fly ash concrete. Furthermore, it effectively reduced blending between bentonite fluid and concrete. On the other hand, the use of starch in concrete mixtures slightly increased the air content, moderately reduced the bleeding, and slightly reduced the compressive strength of concrete. The increase of air by starch is less significant when compared to the case of surfactant type VMA. In the case of mortar test, the addition of surfactant type VMA slightly increased the mortar flow and v-funnel flow time due to enhancement of the air content and viscosity, respectively, of the mixtures, whereas starch ether decreased the mortar flow and increased the v-funnel time due to viscosity increase. By using dosages of surfactant type VMA equal to or higher than 3%, the pressurized dewatering of the mortars was significantly reduced. Furthermore, the use of surfactant type VMA in mortar mixtures with polycarboxylate based superplasticizer effectively reduced the pres

Bored piles are a type of deep foundations which have been and are being widely used in construction engineering such as high-rise buildings, bridges, jetties, and so on. Although bored piles have remarkable advantages over driven piles, the quality of bored piles is frequently affected by many causes of imperfection, which mainly come from the inadequate ground investigation and construction procedures. It can be said that design and quality control of bored piles are two closely related stages. A quality control procedure has to be clearly addressed in the design stage; and decision making in the design, for many cases, has to be based on the testing results of a quality control procedure. Therefore, two major objectives need to be solved in this thesis as: (1) Propose models to calibrate resistance factors for the Load and Resistance Factor Design (LRFD) approach and find a suitable model aiming to directly determine reliability of a bored pile considering some types of defect that may occur in the bored pile. (2) Select a quality control method and evaluate its reliability when applied to bored piles. The thesis consists of chapters, in each of which a new model is proposed, and then is applied for a specific case study. The logicality and succession of the theoretical issues between chapters are systematically presented. In Chapter 2, a history of the development of design approaches is presented, including the Allowable Stress Design (ASD), the Limit State Design (LSD), and the Reliability-Based Design (RBD). Advantages and limitations of each design approach are discussed in detail. This chapter focuses on analyzing the LSD with the use of partial safety factors following the ultimate limit state. In which, the calibration of resistance factors under the framework of the LRFD is one of the main objectives of this thesis. The level II and level III reliability methods are used to calibrate these resistance factors. In Chapter 3, the quality control approaches, Hydraulic Engineering, Civil Engineering and Geosciences

Bored piles are a type of deep foundations which have been and are being widely used in construction engineering such as high-rise buildings, bridges, jetties, and so on. Although bored piles have remarkable advantages over driven piles, the quality of bored piles is frequently affected by many causes of imperfection, which mainly come from the inadequate ground investigation and construction procedures. It can be said that design and quality control of bored piles are two closely related stages. A quality control procedure has to be clearly addressed in the design stage; and decision making in the design, for many cases, has to be based on the testing results of a quality control procedure. Therefore, two major objectives need to be solved in this thesis as: (1) Propose models to calibrate resistance factors for the Load and Resistance Factor Design (LRFD) approach and find a suitable model aiming to directly determine reliability of a bored pile considering some types of defect that may occur in the bored pile. (2) Select a quality control method and evaluate its reliability when applied to bored piles. The thesis consists of chapters, in each of which a new model is proposed, and then is applied for a specific case study. The logicality and succession of the theoretical issues between chapters are systematically presented. In Chapter 2, a history of the development of design approaches is presented, including the Allowable Stress Design (ASD), the Limit State Design (LSD), and the Reliability-Based Design (RBD). Advantages and limitations of each design approach are discussed in detail. This chapter focuses on analyzing the LSD with the use of partial safety factors following the ultimate limit state. In which, the calibration of resistance factors under the framework of the LRFD is one of the main objectives of this thesis. The level II and level III reliability methods are used to calibrate these resistance factors. In Chapter 3, the quality control approaches, Hydraulic Engineering, Civil Engineering and Geosciences

The design of pile foundations requires good estimation of the pile load-carrying capacity and settlement. Design for bearing capacity and design for settlement have been traditionally carried out separately. However, soil resistance and settlement are influenced by each other, and the design of pile foundations should thus consider the bearing capacity and settlement inseparably. This requires the full load–settlement response of piles to be well predicted. However, it is well known that the actual load–settlement response of pile foundations can be obtained only by load tests carried out in situ, which are expensive and time-consuming. In this paper, recurrent neural networks (RNNs) were used to develop a prediction model that can resemble the full load–settlement response of drilled shafts (bored piles) subjected to axial loading. The developed RNN model was calibrated and validated using several in situ full-scale pile load tests, as well as cone penetration test (CPT) data. The results indicate that the developed RNN model has the ability to reliably predict the load–settlement response of axially loaded drilled shafts and can thus be used by geotechnical engineers for routine design practice.

A series of finite element analysis were carried out to study the response of piles under axial vertical load supported on ten types of sands in dry and saturated conditions. From these results, a simplified method was proposed to estimate the ultimate load in bored piles on sand in terms of diameter and length of pile, unit weight of soil, saturated conditions, and indirect measurements of the shear strength derived from the relative density and N-value from SPT. The proposed method, based on 180 cases analyzed, provides a precision of 92%, and constitutes a complementary simplified design tool to estimate the ultimate load of bored piles on sand, La respuesta de diferentes pilotes sometidos a carga vertical axial fue estudiada empleando una serie de análisis mediante elementos finitos, considerando como suelo de fundación diez tipos de arenas en condición seca y saturada. A partir de los resultados obtenidos, se propone un método simplificado para estimar la carga última en pilotes preexcavados sobre arenas, en términos del diámetro y enterramiento del pilote, peso unitario del suelo, condiciones de saturación, y mediciones indirectas de la resistencia al corte del suelo, obtenidas a partir de la densidad relativa y el índice de penetración SPT. El método propuesto, basado en 180 casos analizados, ofrece una precisión de 92%, y constituye una herramienta complementaría de diseño para estimar la carga última de pilotes preexcavados en arenas

A series of finite element analysis were carried out to study the response of piles under axial vertical load supported on ten types of sands in dry and saturated conditions. From these results, a simplified method was proposed to estimate the ultimate load in bored piles on sand in terms of diameter and length of pile, unit weight of soil, saturated conditions, and indirect measurements of the shear strength derived from the relative density and N-value from SPT. The proposed method, based on 180 cases analyzed, provides a precision of 92%, and constitutes a complementary simplified design tool to estimate the ultimate load of bored piles on sand, La respuesta de diferentes pilotes sometidos a carga vertical axial fue estudiada empleando una serie de análisis mediante elementos finitos, considerando como suelo de fundación diez tipos de arenas en condición seca y saturada. A partir de los resultados obtenidos, se propone un método simplificado para estimar la carga última en pilotes preexcavados sobre arenas, en términos del diámetro y enterramiento del pilote, peso unitario del suelo, condiciones de saturación, y mediciones indirectas de la resistencia al corte del suelo, obtenidas a partir de la densidad relativa y el índice de penetración SPT. El método propuesto, basado en 180 casos analizados, ofrece una precisión de 92%, y constituye una herramienta complementaría de diseño para estimar la carga última de pilotes preexcavados en arenas

A series of finite element analysis were carried out to study the response of piles under axial vertical load supported on ten types of sands in dry and saturated conditions. From these results, a simplified method was proposed to estimate the ultimate load in bored piles on sand in terms of diameter and length of pile, unit weight of soil, saturated conditions, and indirect measurements of the shear strength derived from the relative density and N-value from SPT. The proposed method, based on 180 cases analyzed, provides a precision of 92%, and constitutes a complementary simplified design tool to estimate the ultimate load of bored piles on sand, La respuesta de diferentes pilotes sometidos a carga vertical axial fue estudiada empleando una serie de análisis mediante elementos finitos, considerando como suelo de fundación diez tipos de arenas en condición seca y saturada. A partir de los resultados obtenidos, se propone un método simplificado para estimar la carga última en pilotes preexcavados sobre arenas, en términos del diámetro y enterramiento del pilote, peso unitario del suelo, condiciones de saturación, y mediciones indirectas de la resistencia al corte del suelo, obtenidas a partir de la densidad relativa y el índice de penetración SPT. El método propuesto, basado en 180 casos analizados, ofrece una precisión de 92%, y constituye una herramienta complementaría de diseño para estimar la carga última de pilotes preexcavados en arenas

As a part of the Dutch development program Geo-impulse, which aims to half the occurrence of geotechnical failures in civil engineering projects inside the Netherlands by 2015, this master thesis is investigating how to trace imperfections in bored piles at an early stage. The objective is to carry out literature study on suitable methods and then focus the research on one particular method. The basis of the research is the single-hole sonic logging method. Field and laboratory measurements are carried out with the aim to investigate the detection range of the method as well as try to apply more advanced post-processing techniques. Results from the measurements are discussed and also a comparison between single-hole sonic logging and the better standardized test cross-hole sonic logging is made. The results indicate that single-hole sonic logging has a small detection range inside a bored pile, especially compared to cross-hole sonic logging. Also more advanced post-processing techniques fails or make the test to advance to use on a daily basis. Finally the recommendation is to carry on research with other techniques which in scientific papers have showed some promising results.

As a part of the Dutch development program Geo-impulse, which aims to half the occurrence of geotechnical failures in civil engineering projects inside the Netherlands by 2015, this master thesis is investigating how to trace imperfections in bored piles at an early stage. The objective is to carry out literature study on suitable methods and then focus the research on one particular method. The basis of the research is the single-hole sonic logging method. Field and laboratory measurements are carried out with the aim to investigate the detection range of the method as well as try to apply more advanced post-processing techniques. Results from the measurements are discussed and also a comparison between single-hole sonic logging and the better standardized test cross-hole sonic logging is made. The results indicate that single-hole sonic logging has a small detection range inside a bored pile, especially compared to cross-hole sonic logging. Also more advanced post-processing techniques fails or make the test to advance to use on a daily basis. Finally the recommendation is to carry on research with other techniques which in scientific papers have showed some promising results.

Foundations of buildings and structures are laid with various methods, both deep and shallow foundations. Piling is the most common method of deep foundations while spread footings are often used in shallow foundations, especially in buildings with column frame. An alternative is to use a composite pile foundation where piles and spread footings or piles and a base slab are used to carry the loads. Bored piles are in-situ concrete piles formed by excavating or boring a hole in the ground and filling it with concrete or reinforced concrete. The use of bored piles has so far been limited in Sweden; therefore there are no Swedish standards for the design of bored piles. However, there are Swedish guidelines from 1979 for the design of bored piles founded in frictional soils, published by the Swedish Commission on Pile Research. These guidelines are however not valid for bored piles in clay or boulder clay. The purpose of this study is to present and evaluate various design methods in order to make an appropriate choice of design methods and to present guidelines to assess when bored piles are appropriate based on technical and economical aspects. Owing to the method of construction, bored piles can be formed with various sizes, ranging from large piles which are a few meters in diameter with depths that reach one hundred meters to small and short piles. This huge variation in dimensions makes bored piles useful for deep foundations as well as shallow foundations. Bored piles have many advantages compared to driven piles; they are environmentally friendly because they generate low levels of noise and ground vibrations, are able to carry heavy transverse loads as well as vertical loads and they are economically advantageous compared to driven concrete piles at moderate depths. Bored piles, also known as drilled shafts, have many advantages compared to spread footings especially in boulder clay and other dense soils. Bored piles have a much shorter production time, requir

В работе проанализированы основные факторы, определяющие напряженно-деформированное состояние грунта вокруг ствола сваи, а соответственно и его сопротивление по боковой поверхности сваи и несущую способность сваи по грунту. Выявлены основные закономерности изменения коэффициента пористости грунта вокруг ствола сваи, а также предложены расчетные зависимости для определения параметров зоны уплотнения грунта.

Представлены результаты моделирования работы буронабивных свай, изготовленных из напрягающих бетонов. Испытания проведены в двух лотках с искусственно подготовленным основанием на вертикальную выдергивающую нагрузку. По результатам эксперимента построены графики зависимости осевого перемещения сваи от удерживающей способности основания и получено уравнение регрессии для двухфакторного эксперимента. Результаты эксперимента показали, что применение напрягающего бетона обеспечило наличие плотного контакта бетона с грунтом и, следовательно, увеличило силы трения грунта по боковой поверхности сваи, что свидетельствует о целесообразности использования данного эффекта в строительной практике.

В статье дан детальный анализ особенностей работы буровых и буронабивных свайных фундаментов, а также приведен сравнительный анализ технико-экономических показателей устройства свайных фундаментов заводского и площадочного изготовления. Показано, что наиболее эффективно устройство фундаментов из буронабивных свай из напрягающих бетонов, что позволяет при одной и той же несущей способности снизить расход бетона в 1,26 раза, а трудозатраты – 1,35 раза.

В работе разработана методика расчета несущей способности буровых свай из бетона на основе напрягающих цементов. Приведены данные компьютерного моделирования напряженно-деформированного состояния грунтового массива вокруг ствола буровой сваи, которые позволяют определить основные пути повышения их несущей способности.

To ensure performance of large-diameter bored piles, integrity tests are often conducted after pile construction. It is often impractical to inspect 100\% of piles due to high costs and possible delays. Accordingly, the presence of defects may not be fully detected as only a limited number of piles can be inspected. The defect sizes may also be insufficiently predicted based on limited tests. This paper proposes a procedure to predict the occurrence probability of defect and the defect size for piles at a site based on coring examinations supplemented with engineers' experiences. This procedure is formalized in the Bayesian framework. To update and estimate the occurrence probability and size of pile defects, the concepts of occurrence probability of defect and encounter probability are presented. Then, a method to evaluate the encounter probability is formulated. The occurrence probability of defect is updated based on results from on-site coring. After measurements on encountered defects are taken, the defect size distribution is updated using the proposed procedure. Results from numerical examples indicate that the occurrence probability of defect can be estimated using the proposed procedure in a more rational way. The inspection results from on-site coring have a significant influence on the estimated occurrence probability of defect. The uncertainty in defect size is substantially reduced after being updated with the information on defect sizes from on-site coring. Analysis results can assist the specification of pile inspection program to assure given level of quality assurance. (C) 2006 Elsevier Ltd. All rights reserved.

To ensure performance of large-diameter bored piles, integrity tests are often conducted after pile construction. It is often impractical to inspect 100\% of piles due to high costs and possible delays. Accordingly, the presence of defects may not be fully detected as only a limited number of piles can be inspected. The defect sizes may also be insufficiently predicted based on limited tests. This paper proposes a procedure to predict the occurrence probability of defect and the defect size for piles at a site based on coring examinations supplemented with engineers' experiences. This procedure is formalized in the Bayesian framework. To update and estimate the occurrence probability and size of pile defects, the concepts of occurrence probability of defect and encounter probability are presented. Then, a method to evaluate the encounter probability is formulated. The occurrence probability of defect is updated based on results from on-site coring. After measurements on encountered defects are taken, the defect size distribution is updated using the proposed procedure. Results from numerical examples indicate that the occurrence probability of defect can be estimated using the proposed procedure in a more rational way. The inspection results from on-site coring have a significant influence on the estimated occurrence probability of defect. The uncertainty in defect size is substantially reduced after being updated with the information on defect sizes from on-site coring. Analysis results can assist the specification of pile inspection program to assure given level of quality assurance. (C) 2006 Elsevier Ltd. All rights reserved.

To ensure performance of large-diameter bored piles, integrity tests are often conducted after pile construction. It is often impractical to inspect 100\% of piles due to high costs and possible delays. Accordingly, the presence of defects may not be fully detected as only a limited number of piles can be inspected. The defect sizes may also be insufficiently predicted based on limited tests. This paper proposes a procedure to predict the occurrence probability of defect and the defect size for piles at a site based on coring examinations supplemented with engineers' experiences. This procedure is formalized in the Bayesian framework. To update and estimate the occurrence probability and size of pile defects, the concepts of occurrence probability of defect and encounter probability are presented. Then, a method to evaluate the encounter probability is formulated. The occurrence probability of defect is updated based on results from on-site coring. After measurements on encountered defects are taken, the defect size distribution is updated using the proposed procedure. Results from numerical examples indicate that the occurrence probability of defect can be estimated using the proposed procedure in a more rational way. The inspection results from on-site coring have a significant influence on the estimated occurrence probability of defect. The uncertainty in defect size is substantially reduced after being updated with the information on defect sizes from on-site coring. Analysis results can assist the specification of pile inspection program to assure given level of quality assurance. (C) 2006 Elsevier Ltd. All rights reserved.

In this research, centrifuge model pile-load tests were carried out to failure to investigate the behavior of large-diameter bored pile groups with defects. The model piles represented cast-in-place concrete piles 2.0 m in diameter and 15 m in length. Two series of static loading tests were performed. The first series of tests simulated the performance of a pile founded on rock and a pile with a soft toe. The second series of tests simulated the performance of three 2 X 2 pile groups: One reference group without defects, one group containing, soft toes. and one group with two shorter piles not founded on rock. The presence of soft toes and shorter piles in the defective pile groups considerably reduced the pile group stiffness and capacity. As the defective piles were less stiff than the piles without defects, the settlements of the individual piles in the two defective pile groups were different. As a result, the applied load was largely shared by the piles without defects, and the defective pile groups tilted significantly. The rotation of the defective pile groups caused large bending moments to develop in the croup piles and the pile caps. When the applied load was large, bending failure mechanisms were induced even though the applied load was vertical and concentric. The test results confirm findings from numerical analyses in the literature.

In this research, centrifuge model pile-load tests were carried out to failure to investigate the behavior of large-diameter bored pile groups with defects. The model piles represented cast-in-place concrete piles 2.0 m in diameter and 15 m in length. Two series of static loading tests were performed. The first series of tests simulated the performance of a pile founded on rock and a pile with a soft toe. The second series of tests simulated the performance of three 2 X 2 pile groups: One reference group without defects, one group containing, soft toes. and one group with two shorter piles not founded on rock. The presence of soft toes and shorter piles in the defective pile groups considerably reduced the pile group stiffness and capacity. As the defective piles were less stiff than the piles without defects, the settlements of the individual piles in the two defective pile groups were different. As a result, the applied load was largely shared by the piles without defects, and the defective pile groups tilted significantly. The rotation of the defective pile groups caused large bending moments to develop in the croup piles and the pile caps. When the applied load was large, bending failure mechanisms were induced even though the applied load was vertical and concentric. The test results confirm findings from numerical analyses in the literature.

In this research, centrifuge model pile-load tests were carried out to failure to investigate the behavior of large-diameter bored pile groups with defects. The model piles represented cast-in-place concrete piles 2.0 m in diameter and 15 m in length. Two series of static loading tests were performed. The first series of tests simulated the performance of a pile founded on rock and a pile with a soft toe. The second series of tests simulated the performance of three 2 X 2 pile groups: One reference group without defects, one group containing, soft toes. and one group with two shorter piles not founded on rock. The presence of soft toes and shorter piles in the defective pile groups considerably reduced the pile group stiffness and capacity. As the defective piles were less stiff than the piles without defects, the settlements of the individual piles in the two defective pile groups were different. As a result, the applied load was largely shared by the piles without defects, and the defective pile groups tilted significantly. The rotation of the defective pile groups caused large bending moments to develop in the croup piles and the pile caps. When the applied load was large, bending failure mechanisms were induced even though the applied load was vertical and concentric. The test results confirm findings from numerical analyses in the literature.

Quality assurance (QA) tests, such as integrity tests, are routinely conducted to ensure the safety of pile foundations. QA tests provide additional information and result in changes in estimated reliability of pile foundations. This paper aims to formalize a procedure to quantitatively evaluate the impact of routine QA tests on the reliability of pile foundations. Three cases of reliability analyses based on interface coring of large-diameter bored piles are studied; namely, no toe debris detected, toe debris detected without repair, and toe debris detected and repaired. The prior information of the occurrence probability and thickness of toe debris is established based on a practice survey and accumulated QA data. The Bayesian approach is then applied to update the occurrence probability and the mean toe debris thickness based on outcomes of on-site QA tests and remedial actions taken after these QA tests. Subsequently, the reliability of the piles can be updated. The updated reliability can be significantly higher than that before the QA tests. The degree of reliability improvement depends on the pile specifics, the outcomes from the QA tests, and the remedial actions taken after the QA tests.

Quality assurance (QA) tests, such as integrity tests, are routinely conducted to ensure the safety of pile foundations. QA tests provide additional information and result in changes in estimated reliability of pile foundations. This paper aims to formalize a procedure to quantitatively evaluate the impact of routine QA tests on the reliability of pile foundations. Three cases of reliability analyses based on interface coring of large-diameter bored piles are studied; namely, no toe debris detected, toe debris detected without repair, and toe debris detected and repaired. The prior information of the occurrence probability and thickness of toe debris is established based on a practice survey and accumulated QA data. The Bayesian approach is then applied to update the occurrence probability and the mean toe debris thickness based on outcomes of on-site QA tests and remedial actions taken after these QA tests. Subsequently, the reliability of the piles can be updated. The updated reliability can be significantly higher than that before the QA tests. The degree of reliability improvement depends on the pile specifics, the outcomes from the QA tests, and the remedial actions taken after the QA tests.

Quality assurance (QA) tests, such as integrity tests, are routinely conducted to ensure the safety of pile foundations. QA tests provide additional information and result in changes in estimated reliability of pile foundations. This paper aims to formalize a procedure to quantitatively evaluate the impact of routine QA tests on the reliability of pile foundations. Three cases of reliability analyses based on interface coring of large-diameter bored piles are studied; namely, no toe debris detected, toe debris detected without repair, and toe debris detected and repaired. The prior information of the occurrence probability and thickness of toe debris is established based on a practice survey and accumulated QA data. The Bayesian approach is then applied to update the occurrence probability and the mean toe debris thickness based on outcomes of on-site QA tests and remedial actions taken after these QA tests. Subsequently, the reliability of the piles can be updated. The updated reliability can be significantly higher than that before the QA tests. The degree of reliability improvement depends on the pile specifics, the outcomes from the QA tests, and the remedial actions taken after the QA tests.

Defects present in a pile may not be encountered during a cross-hole sonic logging (CSL) test. Even when defects are indeed encountered, they may not always be detected. This paper proposes a probabilistic analysis procedure for evaluating the reliability of CSL, thereby providing a theoretical supplement to existing experimental evaluations of CSL. The reliability of this integrity testing method is represented by the inspection probability, which is expressed as the product of the encountered probability and the detection probability. Mathematical models to calculate the encountered probability are formulated and a detection probability model is suggested based on existing CSL test data. Several examples are presented to illustrate the proposed procedure. The results indicate that there exists a minimum detectable defect size below which the defect cannot be inspected. For a given number of access tubes, the minimum detectable defect size, as a percentage of the pile cross-sectional area, decreases with the pile diameter. The encountered probability can be taken as an index to determine the required number of access tubes. When the target encountered probability is specified as 0.95, three and four access tubes will be sufficient to encounter defects larger than 15 and 5\% of the pile cross-sectional area, respectively.

The failure of a pile is always defined by a certain failure criterion. Several different failure criteria are commonly used, and the pile capacity values associated with each of these failure criteria can be considerably different. For the sake of international harmonization, it is necessary to calibrate the reliability levels associated with various failure criteria and factors for loads and resistances. This paper aims to evaluate the effects of failure criteria and factors for loads and resistances on the reliability of single bored piles. The bias arising from failure criteria is described by a bias factor, which can easily be accommodated in a reliability analysis. A comprehensive database of static load tests of bored piles is utilized to evaluate the bias associated with several failure criteria. Five limit-state design codes for piles are investigated to illustrate the effect of the bias from failure criteria, the effect of factors for loads and resistances, and their combined effect. The results indicate that the bias from failure criteria has a significant influence on the reliability of piles. Similarly, the use of different factors for loads and resistances in various design codes can also cause considerable differences in the calculated reliability. As a result of these effects, the actual reliability levels of any two design codes, assuming the same nominal target reliability index, can differ considerably.

The failure of a pile is always defined by a certain failure criterion. Several different failure criteria are commonly used, and the pile capacity values associated with each of these failure criteria can be considerably different. For the sake of international harmonization, it is necessary to calibrate the reliability levels associated with various failure criteria and factors for loads and resistances. This paper aims to evaluate the effects of failure criteria and factors for loads and resistances on the reliability of single bored piles. The bias arising from failure criteria is described by a bias factor, which can easily be accommodated in a reliability analysis. A comprehensive database of static load tests of bored piles is utilized to evaluate the bias associated with several failure criteria. Five limit-state design codes for piles are investigated to illustrate the effect of the bias from failure criteria, the effect of factors for loads and resistances, and their combined effect. The results indicate that the bias from failure criteria has a significant influence on the reliability of piles. Similarly, the use of different factors for loads and resistances in various design codes can also cause considerable differences in the calculated reliability. As a result of these effects, the actual reliability levels of any two design codes, assuming the same nominal target reliability index, can differ considerably.

Defects present in a pile may not be encountered during a cross-hole sonic logging (CSL) test. Even when defects are indeed encountered, they may not always be detected. This paper proposes a probabilistic analysis procedure for evaluating the reliability of CSL, thereby providing a theoretical supplement to existing experimental evaluations of CSL. The reliability of this integrity testing method is represented by the inspection probability, which is expressed as the product of the encountered probability and the detection probability. Mathematical models to calculate the encountered probability are formulated and a detection probability model is suggested based on existing CSL test data. Several examples are presented to illustrate the proposed procedure. The results indicate that there exists a minimum detectable defect size below which the defect cannot be inspected. For a given number of access tubes, the minimum detectable defect size, as a percentage of the pile cross-sectional area, decreases with the pile diameter. The encountered probability can be taken as an index to determine the required number of access tubes. When the target encountered probability is specified as 0.95, three and four access tubes will be sufficient to encounter defects larger than 15 and 5\% of the pile cross-sectional area, respectively.

The failure of a pile is always defined by a certain failure criterion. Several different failure criteria are commonly used, and the pile capacity values associated with each of these failure criteria can be considerably different. For the sake of international harmonization, it is necessary to calibrate the reliability levels associated with various failure criteria and factors for loads and resistances. This paper aims to evaluate the effects of failure criteria and factors for loads and resistances on the reliability of single bored piles. The bias arising from failure criteria is described by a bias factor, which can easily be accommodated in a reliability analysis. A comprehensive database of static load tests of bored piles is utilized to evaluate the bias associated with several failure criteria. Five limit-state design codes for piles are investigated to illustrate the effect of the bias from failure criteria, the effect of factors for loads and resistances, and their combined effect. The results indicate that the bias from failure criteria has a significant influence on the reliability of piles. Similarly, the use of different factors for loads and resistances in various design codes can also cause considerable differences in the calculated reliability. As a result of these effects, the actual reliability levels of any two design codes, assuming the same nominal target reliability index, can differ considerably.

Defects present in a pile may not be encountered during a cross-hole sonic logging (CSL) test. Even when defects are indeed encountered, they may not always be detected. This paper proposes a probabilistic analysis procedure for evaluating the reliability of CSL, thereby providing a theoretical supplement to existing experimental evaluations of CSL. The reliability of this integrity testing method is represented by the inspection probability, which is expressed as the product of the encountered probability and the detection probability. Mathematical models to calculate the encountered probability are formulated and a detection probability model is suggested based on existing CSL test data. Several examples are presented to illustrate the proposed procedure. The results indicate that there exists a minimum detectable defect size below which the defect cannot be inspected. For a given number of access tubes, the minimum detectable defect size, as a percentage of the pile cross-sectional area, decreases with the pile diameter. The encountered probability can be taken as an index to determine the required number of access tubes. When the target encountered probability is specified as 0.95, three and four access tubes will be sufficient to encounter defects larger than 15 and 5\% of the pile cross-sectional area, respectively.

In Hong Kong large diameter long bored piles and barrettes are often used to support tall buildings to resist both vertical and horizontal loads. These piles penetrate through and may be founded in saprolitic soils or rocks. Generally, the design for side shear resistance (often called skin friction) of large diameter bored piles (drilled caissons or shafts) in saprolites involves considerable uncertainty and design parameters must usually be verified by field tests. In this paper, 28 full-scale load tests on large diameter machine bored piles constructed in various saprolitic soils were reviewed in detail, in particular the degree of mobilization of side shear resistance using a mobilization rating factor. The diameter of these floating piles ranges from 1.0 m to 1.5 m and the depth from 22 m to 75 m. The authors were heavily involved in the recent construction and testing of 12 of these piles. For bored piles constructed under water, 90\% ultimate side shear resistance was mobilized at an average local pile displacement of 1.9\% of the pile diameter with a 95\% confidence range of 0.9\% to 3.0\%. For piles constructed under bentonite, ultimate side shear resistance was achieved at a local pile displacement of 1\% of the pile diameter. For non-grouted bored piles constructed under water, the mobilized side shear resistance lies between 0.5 (N) over bar and 2.0 (N) over bar (kPa) and (β) over bar values fall within 0.1 and 0.5, with average values of 1.2 (N) over bar (kPa) and 0.3 respectively. Post-grouting improves the capacity of side shear resistance by a factor of about 2 as compared with the non-grouted piles constructed under water. On the contrary, piles constructed under bentonite show a reduction of capacity of side shear resistance between 50\% and 70\% depending on the method of analysis.

In Hong Kong large diameter long bored piles and barrettes are often used to support tall buildings to resist both vertical and horizontal loads. These piles penetrate through and may be founded in saprolitic soils or rocks. Generally, the design for side shear resistance (often called skin friction) of large diameter bored piles (drilled caissons or shafts) in saprolites involves considerable uncertainty and design parameters must usually be verified by field tests. In this paper, 28 full-scale load tests on large diameter machine bored piles constructed in various saprolitic soils were reviewed in detail, in particular the degree of mobilization of side shear resistance using a mobilization rating factor. The diameter of these floating piles ranges from 1.0 m to 1.5 m and the depth from 22 m to 75 m. The authors were heavily involved in the recent construction and testing of 12 of these piles. For bored piles constructed under water, 90\% ultimate side shear resistance was mobilized at an average local pile displacement of 1.9\% of the pile diameter with a 95\% confidence range of 0.9\% to 3.0\%. For piles constructed under bentonite, ultimate side shear resistance was achieved at a local pile displacement of 1\% of the pile diameter. For non-grouted bored piles constructed under water, the mobilized side shear resistance lies between 0.5 (N) over bar and 2.0 (N) over bar (kPa) and (β) over bar values fall within 0.1 and 0.5, with average values of 1.2 (N) over bar (kPa) and 0.3 respectively. Post-grouting improves the capacity of side shear resistance by a factor of about 2 as compared with the non-grouted piles constructed under water. On the contrary, piles constructed under bentonite show a reduction of capacity of side shear resistance between 50\% and 70\% depending on the method of analysis.

In Hong Kong large diameter long bored piles and barrettes are often used to support tall buildings to resist both vertical and horizontal loads. These piles penetrate through and may be founded in saprolitic soils or rocks. Generally, the design for side shear resistance (often called skin friction) of large diameter bored piles (drilled caissons or shafts) in saprolites involves considerable uncertainty and design parameters must usually be verified by field tests. In this paper, 28 full-scale load tests on large diameter machine bored piles constructed in various saprolitic soils were reviewed in detail, in particular the degree of mobilization of side shear resistance using a mobilization rating factor. The diameter of these floating piles ranges from 1.0 m to 1.5 m and the depth from 22 m to 75 m. The authors were heavily involved in the recent construction and testing of 12 of these piles. For bored piles constructed under water, 90\% ultimate side shear resistance was mobilized at an average local pile displacement of 1.9\% of the pile diameter with a 95\% confidence range of 0.9\% to 3.0\%. For piles constructed under bentonite, ultimate side shear resistance was achieved at a local pile displacement of 1\% of the pile diameter. For non-grouted bored piles constructed under water, the mobilized side shear resistance lies between 0.5 (N) over bar and 2.0 (N) over bar (kPa) and (β) over bar values fall within 0.1 and 0.5, with average values of 1.2 (N) over bar (kPa) and 0.3 respectively. Post-grouting improves the capacity of side shear resistance by a factor of about 2 as compared with the non-grouted piles constructed under water. On the contrary, piles constructed under bentonite show a reduction of capacity of side shear resistance between 50\% and 70\% depending on the method of analysis.

Firma zabývající se modernizací kolejových vozidel postupně modernizuje svůj výrobní areál. Velkou investicí je stavba nové haly lakovny, souběžně s rekonstrukcí sousední výrobní haly a nové napojení areálu na vodovodní řád, plynovod a novou trafostanici. Práce obsahuje technologické předpisy pro vrtané piloty a pro montáž horní konstrukce prefabrikované železobetonové haly lakovny. Technologické předpisy jsou doplněny návrhem strojní sestavy, zařízením staveniště, kontrolními a zkušebními plány, rozpočtem stavby, bezpečnost práce, časový plán a srovnání použití dvou variant jeřábů z finančního a časového hlediska., Company engaged in modernization of locomotive vehicles progressively modernizing their industrial estate. A big investment become realization of new industrial hall for vehicle coating, simultaneously with a reconstruction of neighbouring production hall and a new connection to the water main, gas main and a new transformer station. The bachelor thesis includes technological regulations of bored piles and for assembly upper prefabricated reinforced concrete construction of coating hall. Technological regulations are supplemented by draft of the suitable machinery, equipment of construction site and inspectional and trial plans, work safety, time schedule and comparison of two variants of the cranes and all will be feasible in terms of construction rate and financing.

Náplní této bakalářské práce je návrh pilotového založení stavby v daných geologických podmínkách. Výchozími podklady přitom jsou zpráva inženýrsko-geologického průzkumu lokality a schéma zatížení základů. Návrh a výpočet je proveden s pomocí tabulkového procesoru Excel a geotechnického software GEO5 – modul Pilota. Oba výpočty jsou nakonec srovnány s výstupem z programu Plaxis 2D., The objective of this bachelor’s thesis is design of pile foundation of a building in specific geological conditions. The design is based on engineering geology report of the area and a scheme of loads on foundations. Calculations are executed in spreadsheet software Excel and in geotechnical software GEO5 – Pile module. Finally, these calculations are compared with Plaxis 2D output.

Obsahem práce je stavebně technologický projekt novostavby souboru tří bytových domů Kampus rezidenční areál II nacházející se v Brně - Bohunicích. Práce obsahuje technologické předpisy pro vrtané piloty a železobetonový monolitický strop. Technologické předpisy jsou doplněny návrhem strojní sestavy, zařízením staveniště a kontrolními a zkušebními plány na tyto procesy. Řešena je i bezpečnost práce, časový a finanční plán, rozpočet stavby a plán zajištění materiálových zdrojů. V diplomové práci je řešena i smlouva o dílo a detaily střešní konstrukce., The subjekt of my bachelor thesis is the construction technological project of the new complex of three buildings Campus residential area II located in Brno - Bohunice. The diploma thesis includes technological regulations of piles and cast-in-place reinforced concrete floor. Technological regulations are supplemented by draft of the suitable machinery, equipment of construction site and inspectional and trial plans for these processes. The author also deals with work safety, time and financial plan, budget of substructure and plan for securing material resources. The thesis also addressed work contract and detailsof the roof structure.

Diplomová práce se zabývá návrhem a statickým posouzením pažení stavební jámy realizované za účelem výstavby polyfunkčního domu v Brně Husovicích. Úvodní část práce shrnuje základní vstupní informace o zájmové lokalitě včetně výstupů inženýrsko-geologického průzkumu a podává přehled o možnostech zajištění stavebních jam. Stěžejní část práce popisuje navržení a posouzení vybrané varianty pažení, následné zhodnocení výsledků a technologický postup výstavby. Navržená konstrukce je doplněna o statické výpočty a výkresovou dokumentaci, které jsou součástí přílohy., This diploma thesis describes the design and static assessment carried shoring excavation pit for the construction of a multifunctional building in Brno Husovice. Introductory part summarizes the basic input information on the area of interest, including outputs of engineering-geological survey and gives an overview of the options pits. The main part describes the design and assessment of selected variant of shoring, the subsequent evaluation of the results and the technological progress of construction. The proposed design is complemented by structural calculations and construction plans.

Bakalářská práce obsahuje řešení pro postup výstavby spodní hrubé stavby jedné budovy v komplexu Nemocnice Znojmo. Práce se zabývá technologickými předpisy pro základové konstrukce, zejména technologickým postupem pro opěrnou zeď. Dále se zabývá návrhem strojní sestavy, časového plánu a položkového rozpočtu. Podkladem pro vypracování byla souhrnná technická zpráva ke stavebnímu řízení včetně výkresové dokumentace., Thesis comprises solutions for the process of construction of the substructure of a building in the complex Znojmo Hospital. The work deals with technological requirements for foundation construction, especially technique for retaining wall. It also deals with the design mechanical assemblies, schedule and itemized budget. The basis for the preparation of the summary technical report for building management including drawings.