7.2 Ingenieurbau
Filtern
Dokumenttyp
- Beitrag zu einem Tagungsband (23) (entfernen)
Schlagworte
- Structural Health Monitoring (5)
- Structural health monitoring (4)
- Environmental effects (2)
- Grout (2)
- Interface (2)
- Offshore (2)
- Repair (2)
- Soil-structure interaction (2)
- Wind (2)
- Analysis of variance (1)
- Artificial Intelligence (1)
- Artificial intelligence (1)
- BIM (1)
- Bayesian System Identification (1)
- Bayesian methods (1)
- Bayesian system identification (1)
- Bayesian updating (1)
- Belastungsversuch (1)
- Box-Behnken (1)
- Compaction Grouting (1)
- Compaction grouting (1)
- Computer Vision (1)
- Crack Luminescence (1)
- Crack formation (1)
- Crack pattern (1)
- Cracks (1)
- Cyclic load (1)
- Damage identification (1)
- Digital Image Correlation (DIC) (1)
- Digital Models (1)
- Digital twin (1)
- Drop Tests (1)
- Energy (1)
- Environmental changes (1)
- Finite Elemente Simulation (1)
- Foundation reliability analysis (1)
- Grouted Connection (1)
- Grouted connection (1)
- Grouting (1)
- Großer Fallturm Horstwalde (1)
- Injection Sequence (1)
- Material Point Method (MPM) (1)
- Material tests (1)
- Microfine Cement (1)
- Mixed formulation (1)
- Modalanalyse (1)
- Monopile installation risks (1)
- Non-Destructive Evaluation (1)
- Numerical modelling (1)
- Offshore Pile Foundation (1)
- Offshore Wind Energy (1)
- Offshore foundations (1)
- Offshore pile foundation (1)
- Offshore wind energy (1)
- Optimal Sensor Placement (1)
- Probabilistic modelling (1)
- Probability of Detection (1)
- Prädiktive Instandhaltung (1)
- Rehabilitation (1)
- Reliability (1)
- Research data management (1)
- SHM (1)
- SHM environmental bridges (1)
- Schwingungsdynamik (1)
- Shearing (1)
- Shell Buckling (1)
- Shrinkage Reducing Admixture (1)
- Soil-Structure-Interaction (1)
- Soil-pile interaction (1)
- Spatially varying ground conditions (1)
- Static load (1)
- Structural systems (1)
- Superplasticizer (1)
- Supplementary Cementitious Materials (1)
- Supplementary cementitious materials (1)
- System Identification (1)
- Tensile Capacity (1)
- Umwelteinflüsse (1)
- Value of Information (1)
- Wind Energy (1)
- building information modelling (1)
- structural health monitoring (1)
- structural integrity management (1)
- support structures (1)
- temperature (1)
Organisationseinheit der BAM
- 7.2 Ingenieurbau (23) (entfernen)
The authors are currently investigating the possibility to apply compaction grouting for offshore pile foundations (Jacket piles as well as monopiles) as a possible retrofitting technique for an optimised foundation concept. In this research project, we are developing a design approach aiming to predict the ideal amount and properties of a grout for a specific soil situation and desired improvement of pile bearing capacity after Installation and during service time. Both numerical and experimental tests have been carried out to investigate the injection process during which a highly viscous grout is injected into the soil under high pressure to displace and compact the surrounding soil without fracturing it. The implicit Material Point Method (MPM) based on a mixed formulation is the numerical technique chosen to deal with the expected large deformations and the arbitrary shape of the developing grout bulb. The usage of MPM prevents both the need of remeshing and the numerical instability induced by extensive mesh distortion. For validation with experimental results, we have constructed a testing chamber with one transparent sidewall. This chamber enables us to observe the injection process directly at the transparent vertical window and to measure the in-plane soil displacements and strains by means of the Digital Image Correlation (DIC) technique.
The results already reveal the interrelation of soil and grout properties for a successful usage of this common ground improvement technique.
The response of many geotechnical systems, whose structural behavior depends on shearing effect, is closely related to soil structure interaction phenomenon. Experimentally it is found that the localisation of these effect happens at a narrow soil layer next to the structure. Numerically, this behavior can be modelled through inter-face elements and adequate constitutive models. In this work, a constitutive model in the framework of Gen-eralized Plasticity for sandy soils has been chosen to be adapted for the interface zone. From the direct shear experiments a sandy soil at loose and dense states under different normal pressures is considered. The adapted constitutive model is able to reproduce contraction and dilatation of the soil according to its relative density and it shows a good agreement with the experimental data.
Remediation of Cracks Formed in Grouted Connections of Offshore Energy Structures under Static Loads
(2018)
The future energy demand necessitates the exploration of all potential energy sources both onshore and offshore. Global trend has shifted towards offshore energy, which can be obtained from either carbon intensive or renewable options, hence requiring structures such as rigs, platforms, and monopiles. Most of these structures adopt easily installable construction techniques, where lower foundation need to be connected with the super structure by mean of grouted composite joints. Generally, these composite connections have exterior sleeve, interior pile and infill grout. Being located in remote offshore conditions, connections can experience considerable adverse loading during their lifetimes. Degradations were reported inside similar connections, which were installed in last three decades. Besides, grouting in the offshore sites may often be proven difficult, which eventually leads to reduced capacity of connections in the long run. Thus, repair and rehabilitation of such connections should be planned ahead to minimize operational delays and costs in the future. This study aims at characterizing the nature of crack generation in grouted connections and thereby identifying the potential of repair using suitable repair material. Scaled grouted joints were manufactured using a novel mold, and connections were loaded under static load to visualize the main failure pattern. The failure mechanism and loading capacity are found compatible to previous results from earlier literature. Grouted connection was then repaired using cementitious injectable grout. The effectiveness of the repair system is also discussed.