Recommendations on Piling (EA Pfähle)

This handbook provides a complete and detailed overview of piling systems and their application. The design and construction of pile foundations is based on Eurocode 7 as well as the European Execution Standards EN 1536 (Bored Piles), EN 12699 (Displacement Piles) and EN 14199 (Micropiles) and respective German application documents. These Recommendations also deal with • categorisation of piling systems; • actions on piles from structural loading, negative skin friction and lateral pressure; • pile resistances from static and dynamic load pile tests as well as extensive tables with the pile load–bearing capacity of nearly all piling systems based on values from empirical data; • pile groups; • execution of static and dynamic load tests and integrity tests; • load–bearing behaviour and verifi cations for piles under cyclical, dynamic and impact actions, e.g. for onshore and offshore wind energy structures; • quality assurance and guidelines for the execution. Appendices with numerous calculation examples and the analysis and interpretation of dynamic load tests complete the work. The Piling Recommendations, EA–Piling, elaborated by the Piling Working Group of the German Geotechnical Society (DGGT), which is identical with the German Pile Standards’ Committee, are intended to provide assistance for engineers active in the design, calculation, construction, supervision and control of pile foundations. The Recommendations can thus be considered as widely accepted technical rules and as a supplement to the available codes and standards.

Members of the AK 2.1 Piling Committee of the German Geotechnical Society V Preface of the English Version of the Recommendations of the Piling Committee of the German Geotechnical Society VII Preface of the 2nd German edition IX 1 Introduction to the Recommendations and their Application Principles 1 1.1 National and International Regulations for Piling Works 1 1.2 Types of Analysis and Limit States using the Partial Safety Factor Approach 2 1.3 Planning and Testing Pile Foundations 7 2 Pile Systems 9 2.1 Overview and Classification into Pile Systems 9 2.2 Pile Construction 12 2.3 Foundation elements similar to piles 25 3 Pile Foundation Design and Analysis Principles 27 3.1 Pile Foundation Systems 27 3.2 Geotechnical Investigations for Pile Foundations 32 3.3 Classification of Soils for Pile Foundations 39 3.4 Pile Systems for the Execution of Excavations and for Retaining Structures 40 3.5 Piles for the Stabilisation of Slopes 43 3.6 Use of sacrificial Linings 44 4 Actions and Effects 47 4.1 Introduction 47 4.2 Pile Foundation Loads Imposed by the Structure 48 4.3 Installation Effects on Piles 48 4.4 Negative Skin Friction 49 4.5 Lateral Pressure 54 4.6 Additional Effects on Raking Piles Resulting from Ground Deformations 62 4.7 Foundation Piles in Slopes and at Retaining Structures 65 5 Bearing Capacity and Resistances of Single Piles 69 5.1 General 69 5.2 Determining Pile Resistances from Static Pile Load Tests 70 5.3 Determining Pile Resistances from Dynamic Pile Load Tests 72 5.4 Axial Pile Resistances Based on Empirical Data 75 5.5 Bored Piles with Enlarged Bases 113 5.6 Additional Methods Using the EC 7–1 and EC 7–2 Handbooks 114 5.7 Pile Resistances for Grouted Shafts and Bases. 114 5.8 Resistances of Piles Under Lateral Loads 115 5.9 Pile Resistances Under Dynamic Actions 116 5.10 Internal Pile Capacity 116 5.11 Numerical Analyses of the Capacity of Single Piles 119 6 Stability Analyses 121 6.1 Introduction 121 6.2 Limit State Equations 121 6.3 Bearing Capacity Analysis 122 6.4 Serviceability Analysies 125 6.5 Pile Groups and Grillages 127 6.6 Piled Raft Foundations 127 7 Grillage Analysis 129 7.1 AnalysisModels and Procedures 129 7.2 Non–linear Pile Bearing Behaviour in Grillage Analysis 130 8 Analysis and Verification of Pile Groups 131 8.1 Actions and Effects 131 8.2 Bearing Capacity and Resistances of Pile Groups 133 8.3 Bearing Capacity Analyses 152 8.4 Serviceability Analyses 156 8.5 Higher Accuracy Pile Group Analyses 157 9 Static Pile Load Tests 159 9.1 Introduction 159 9.2 Static Axial Pile Load Tests 159 9.3 Static Lateral Load Test 182 9.4 Static Axial Load Tests on Micropiles (Composite Piles) 194 10 Dynamic pile load tests 209 10.1 Introduction. 209 10.2 Range of Application and General Conditions 209 10.3 Theoretical Principles 210 10.4 Description of Testing Methods, Test Planning and Execution 213 10.5 Evaluation and Interpretation of Dynamic Load Tests 225 10.6 Calibrating Dynamic Pile Load Tests 231 10.7 Qualifications of Testing Institutes and Personnel 234 10.8 Documentation and Reporting 234 10.9 Testing Driving Rig Suitability 236 11 Quality Assurance during Pile Execution 239 11.1 Introduction. 239 11.2 Bored Piles 239 11.3 Displacement Piles 253 11.4 Grouted Micropiles (Composite Piles). 255 12 Pile Integrity Testing 259 12.1 Purpose and Procedures 259 12.2 Low Strain Integrity Tests 260 12.3 Ultrasonic Integrity Testing 270 12.4 Testing Piles by Core Drilling. 279 12.5 Other Specific TestingMethods 282 13 Bearing Capacity and Analyses of Piles under Cyclic, Dynamic and Impact Actions 285 13.1 Introduction 285 13.2 Cyclic, Dynamic and Impact Actions 286 13.3 Supplementary Geotechnical Investigations 292 13.4 Bearing Behaviour and Resistances under Cyclic Loads 294 13.5 Bearing Behaviour and Resistances under Dynamic Loads 299 13.6 Bearing Behaviour and Resistances under Impact Loads 300 13.7 Stability Analyses of Cyclic, Axially Loaded Piles 301 13.8 Stability Analyses of Cyclical, Laterally Loaded Piles 304 13.9 Stability Analyses of Dynamic or Impact–loaded Piles 306 Annex A Terms, Partial Safety Factors and Principles for Analysis 307 Annex B Example Calculations for Pile Resistance Analysis and Verifications 331 Annex C Examples of Dynamic Pile Load Testing and Integrity Testing 395 Annex D Analysis Methods and Examples for Cyclically Loaded Piles (Informative) 417 Literatur 459 List of Advertisers 469

The "Piling" working group AK 2.1 of the German Society for Geotechnics (DGGT) consists of about 20 experts from science, industry, construction administration and client organisations and has the same members as the standards committee "Piling" of the NABau.