Offshore Dynamic Pile Load Testing & Pile Driving Monitoring Services

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1 Offshore Dynamic Pile Load Testing & Pile Driving Monitoring Services Specialist Real-time Monitoring of: Soil Resistance & Pile Capacity / Driving Stresses / Hammer Performance Pile Driving is Pile Testing

2 PILE DRIVING MONITORING SERVICES AIMS OF PILE DRIVING MONITORING To establish pile ultimate bearing capacity and confirm pile design assumptions To assess and manage risk of pile tip buckling To allow development of pile driving prediction numerical models To evaluate pile fatigue resulting from driving process To permit the development of a calibrated model for the back analysis of non-instrumented piles WHAT DOES PILE DRIVING MONITORING ENTAIL? Attaching strain gauges and accelerometers to the top of the pile The striking of the pile with the hammer imparts stress and velocity waves (and their reflection from the pile:soil interface) which are recorded and analysed to determine: 1. Actual hammer energy that is tranferred to the pile 2. The pile s ultimate bearing capacity and the soil resistance under continuous driving conditions 3. Axial stress distribution along the pile BENEFITS OF PILE DRIVING MONITORING Real time Quality Control for installation operations - Pile driving monitoring is the only way to evaluate the stresses induced anywhere in the pile. Design Verification - Results can be used to confirm axial pile capacity - especially important where there is a risk of premature driving refusal or of encountering challenging geological conditions. Design and Installation Cost Optimisation - Results can be used to validate the assumptions made during the pile design and installation assessment. In recent projects, this has resulted in significant cost savings in terms of pile dimensions and associated installation timescales.

3 CA Instrumentation capabilities include both above water and under water pile driving monitoring

4 ADVANCED INTERPRETATION AND ANALYSIS CA Instrumentation are a leading provider of advanced interpretation of the pile driving monitoring data. Utilising years of experience, CA Instrumentation are able to provide the following services: Signal matching analysis utilising CAPWAP - a software program that calculates total bearing capacity of a pile as well as resistance distribution along the shaft and at the toe Assessment of in-situ pile capacity in case of premature pile refusal Pile fatigue assessment Calibration of the hammer/pile/soil numerical model for site specific driving predictions Construction of a numerical based soil model calibrated through analysis of instrumented pile tests which permits the calculation of pile capacity for none instrumented piles. This method is considered as a pile test by Eurocode 7 and allows for a substantial decrease of the applicable safety factors Definition of pile driving criteria for pile tip integrity while driving in soft rock for instrumented piles and non-instrumented piles OFFSHORE OPERATIONS The offshore team typically comprises of two to four personnel, headed by an experienced geotechnical engineer certified by the Deep Foundation Institute. The team can provide round the clock assistance on all piling issues, whilst the on-site analysis of data enables a preliminary assessment of the hammer/pile/soil system to be given virtually in real time. CA Instrumentation engineers are familiar with the offshore environment and trained to liaise with barge masters and deck foreman to minimise interference with the installation schedule. The equipment is thoroughly checked before the operations, and mobilised with 100% redundancy. A well planned pile driving monitoring operation should normally not incur any barge standing time. EQUIPMENT CA Instrumentation operate the Pile Driving Analyser (PDA) PAX acquisition unit manufactured by PDI, which is widely regarded as the most reliable system on the market. The PDA acquisition units are deployed in conjunction with PDI manufactured strain gauges and accelerometers, and the data captured is analysed using the latest versions of GRL WEAP, PDA-W and CAPWAP. EQUIPMENT HIRE AND PROVISION OF TRAINING COURSES Equipment hire and provision of specialist training is undertaken by G-Octopus, a sister company of CA Instrumentation. G-Octopus are also an accredited training company, providing theoretical courses and practical training on pile driving monitoring and dynamic pile load testing. These can be provided at any location. G-Octopus is an approved distributor of PDI equipment. PILE DRIVING ENGINEERING

5 RECENT PROJECT EXPERIENCE Extensive experience of offshore pile driving monitoring within the oil and gas sector and more recently, in offshore wind power, has provided CA Instrumentation with an enviable breadth of worldwide project experience. Borkum West II, North Sea, * Under water pile driving monitoring (30m depth) of offshore wind turbine tripod foundations using subsea cable technology Assessment of the pile bearing capacity by signal matching using CAPWAP software Assessment of soil set-up behaviour based on restrike tests including tests conducted >1 year after installation Gwynt Y Môr, Irish sea, 2012* Above water pile driving monitoring (30m) of offshore substation Platform jacket foundations using standard PDA cable technology Assessment of the pile bearing capacity by signal matching using CAPWAP software Restrike tests AGM-N Platform, Anguille Redevelopment, 2010* Above water pile driving monitoring (100m) using standard PDA cable technology and wireless technology Assessment of soil resistance to driving (SRD) by the global method using OPILE and GRL WEAP software, and by the signal matching method using CAPWAP software. OTHER PROJECTS INCLUDE:* IKALOU & OLOWI, Offshore Gabon 2009: underwater Pile Driving Monitoring of skirt piles jackets for Saipem ENI & CNR ARZEW AMMONIA, Algeria; PORTO NUEVO, Colombia: procurement of pile testing equipment, training of personnel, data analysis and processing, pile capacity assessment, adjusted pile acceptance criteria. PECIKO, TUNU, Yemen; BONGKOT, Thailand; SISI NUMBI, Indonesia: pile testing supervision, pile capacity assessment and pile acceptance of numerous offshore jackets and jetties in South East Asia on behalf of TOTAL. SIRRI, SOUTH PARS, AL KHALIJ, ZULUF, Persian Gulf: extensive experience in the perso-arabic Gulf, in complex carbonate partially cemented soils and weak rocks. *Projects previously undertaken under G-Octopus

6 CA Instrumentation/G-Octopus Immeuble les Fontenelles 1 rue de Craïova 92000, Nanterre, France t: e: [email protected] / [email protected] / CA Instrumentation Collingwood Buildings, 38 Collingwood Street, Newcastle upon Tyne NE1 1JF United Kingdom t: e: [email protected] CA Instrumentation and G-Octopus are trading names of CATHIE Associates.