7.2 Ingenieurbau
Filtern
Dokumenttyp
- Beitrag zu einem Tagungsband (82) (entfernen)
Sprache
- Englisch (66)
- Deutsch (15)
- Mehrsprachig (1)
Schlagworte
- Ground vibration (6)
- Structural health monitoring (6)
- Fatigue (5)
- Structural Health Monitoring (5)
- Model interpolation (4)
- Vibration measurements (4)
- Building vibration (3)
- Damage localization (3)
- Hammer impact (3)
- Impact (3)
- Layered soil (3)
- Reliability (3)
- Temperature rejection (3)
- Bahnerschütterungen (2)
- Bayesian updating (2)
- Cable failure (2)
- Cable-stayed bridge (2)
- Container loading (2)
- Damage characterization (2)
- Drop test (2)
- Environmental effects (2)
- Erschütterungen (2)
- Fault detection (2)
- Foundation load (2)
- Grout (2)
- High-strength concrete (2)
- Inspection planning (2)
- Interface (2)
- Linear parameter varying systems (2)
- Load vector (2)
- Modalanalyse (2)
- Monitoring (2)
- Offshore (2)
- Planar tomography (2)
- Repair (2)
- Risk (2)
- SDDLV (2)
- Soil-structure interaction (2)
- Soil-wall-floor model (2)
- Statistical evaluation (2)
- Structural systems (2)
- Subspace-based method (2)
- Subspace-based residual (2)
- Train passage (2)
- Train-induced ground vibration (2)
- Ultrasonic testing (2)
- Vehicle-track interaction (2)
- Vibration (2)
- Wind (2)
- 2-span bridge (1)
- Achsfolgespektren (1)
- Acoustic emission testing (1)
- Amplitude-charge weight laws (1)
- Amplitude-distance laws (1)
- Analysis of variance (1)
- Analytical Design Methods (1)
- Ansys Autodyn (1)
- Apartment building (1)
- Artificial Intelligence (1)
- Artificial intelligence (1)
- Attenuation (1)
- Autonomous underwater vehicles (1)
- Axle impulses (1)
- Axle loads (1)
- Axle-sequence spectrum (1)
- BIM (1)
- Bauteile (1)
- Bauwerke (1)
- Bayesian System Identification (1)
- Bayesian methods (1)
- Bayesian system identification (1)
- Belastungsversuch (1)
- Big Data (1)
- Bodenvariabilität (1)
- Bodenübertragungsfunktion (1)
- Box-Behnken (1)
- Bridges (1)
- Brücke (1)
- Brücken (1)
- Changing process noise (1)
- Chemisoprtion (1)
- Climate chamber (1)
- Column/wall resonance (1)
- Compaction Grouting (1)
- Compaction grouting (1)
- Compressive Cyclic loading (1)
- Compressive cyclic loading (1)
- Compressive strength (1)
- Computer Vision (1)
- Conductor (1)
- Coupler systems (1)
- Crack Luminescence (1)
- Crack detection (1)
- Crack formation (1)
- Crack growth (1)
- Crack pattern (1)
- Cracks (1)
- Cyber security (1)
- Cyclic load (1)
- DEM (1)
- DUCON® (1)
- Damage detection (1)
- Damage identification (1)
- Datenmanagement (1)
- Deterioration (1)
- Digital Image Correlation (DIC) (1)
- Digital Models (1)
- Digital twin (1)
- Dispersionsmessung (1)
- Displacements (1)
- Drone (1)
- Drop Tests (1)
- Drop tower (1)
- Drucker-Prager (1)
- Ductility (1)
- Dynamische Bodensteifigkeit (1)
- E-modulus (1)
- Earth (1)
- Earth masonry (1)
- Elastische Gebäudelagerung (1)
- Elastische Gleiselemente (1)
- Emission (1)
- Energy (1)
- Environmental changes (1)
- Erschütterungsausbreitung (1)
- Erschütterungsminderung (1)
- Erschütterungsprognose (1)
- Evaluation (1)
- Excitation forces (1)
- Explosion-induced ground vibrations (1)
- Fallturm (1)
- Faseroptik (1)
- Fault detectionchanging (1)
- Feuchte (1)
- Filter effects (1)
- Finite Elemente Simulation (1)
- Finite element models (1)
- Floor resonance (1)
- Foundation Pile (1)
- Foundation reliability analysis (1)
- Freight train (1)
- Freileitung (1)
- Gleiströge (1)
- Granular Cohesive Materials (1)
- Ground vibration measurements (1)
- Grouted Connection (1)
- Grouted connection (1)
- Grouting (1)
- Großer Fallturm Horstwalde (1)
- HAZID (1)
- HTLS (1)
- Halbraum (1)
- Hard impact (1)
- Harter Anprall an Stahlbetonstrukturen (1)
- High-Rise Building (1)
- High-speed (1)
- High-speed train (1)
- Horizontal stress (1)
- Immission (1)
- Impact damage on reinforced concrete (1)
- Impakt (1)
- Inertial Interaction (1)
- Injection Sequence (1)
- Inspection (1)
- Irregular ballast (1)
- Irregular soil (1)
- Irregularities (1)
- Kinematic Interaction (1)
- Knudsen effect (1)
- Laboratory beam structure (1)
- Layered soils (1)
- Lehm (1)
- Load-bearing (1)
- Long-span bridge (1)
- Macromechanical Sample Strength (1)
- Maschinenbetrieb (1)
- Material Point Method (MPM) (1)
- Material moisture (1)
- Material tests (1)
- Mauerwerk (1)
- Measurement (1)
- Measurements (1)
- Micro-reinforcement (1)
- Microfine Cement (1)
- Micromechanical Tensile Failure (1)
- Minderungsmaßnahmen (1)
- Mixed formulation (1)
- Mobile elements (1)
- Modal Analysis (1)
- Modal force spectrum (1)
- Modes (1)
- Moisture (1)
- Molecular diffusion (1)
- Monopile installation risks (1)
- Multiple impact (1)
- NDT (1)
- Nachgiebigkeiten (1)
- Non destructive testing (1)
- Non-Destructive Evaluation (1)
- Non-destructive testing (1)
- Numeric simulation (1)
- Numerical damage simulation (1)
- Numerical modeling (1)
- Numerical modelling (1)
- Office building (1)
- Office tower (1)
- Offshore Pile Foundation (1)
- Offshore Wind Energy (1)
- Offshore foundations (1)
- Offshore pile foundation (1)
- Offshore steel structures (1)
- Offshore wind energy (1)
- Offshore wind turbines (1)
- Optimal Sensor Placement (1)
- Passenger train (1)
- Physisorption (1)
- Pile Foundation (1)
- Post-impact evaluation (1)
- Prediction of explosion induced ground and building vibration (1)
- Probabilistic modelling (1)
- Probability of Detection (1)
- Process noise (1)
- Propagation from a tunnel (1)
- Prädiktive Instandhaltung (1)
- Quasi-static and dynamic tests (1)
- Radar (1)
- Railway (1)
- Railway bridge (1)
- Railway tunnel (1)
- Randomly heterogeneous soil (1)
- Rechenmodelle (1)
- Rehabilitation (1)
- Reinforced concrete structure (1)
- Reinforcement (1)
- Research data management (1)
- Residential building (1)
- Residual evaluation (1)
- Risk-based design (1)
- SHM (1)
- SHM environmental bridges (1)
- Safety (1)
- Scattering (1)
- Scherwellengeschwindigkeit (1)
- Schubmodul (1)
- Schwingungsdynamik (1)
- Shearing (1)
- Shell Buckling (1)
- Shrinkage Reducing Admixture (1)
- Simple prediction (1)
- Size effect (1)
- Slab track (1)
- Slenderness effect (1)
- Soft impact (1)
- Soil properties (1)
- Soil-Structure-Interaction (1)
- Soil-building interaction (1)
- Soil-building resonance (1)
- Soil-pile interaction (1)
- Spatially varying ground conditions (1)
- Static load (1)
- Statistical method (1)
- Statistical tests (1)
- Statistische Auswertung (1)
- Steel structures (1)
- Stereo photogrammetry (1)
- Strength (1)
- Subspace methods (1)
- Superplasticizer (1)
- Supplementary Cementitious Materials (1)
- Supplementary cementitious materials (1)
- Surface Foundation (1)
- Surface-tunnel reduction (1)
- System Identification (1)
- Temperature effects (1)
- Tensile Capacity (1)
- Time-variant reliability (1)
- Tomographic damage evaluation (1)
- Tragfähigkeit (1)
- Train speed (1)
- Transfer function (1)
- Transmission (1)
- Tunnel (1)
- Tunnel-pile transfer (1)
- UHPC (1)
- Umwelteinflüsse (1)
- Uncertainty (1)
- Uncertainty in reference (1)
- Value of Information (1)
- Varying stiffness (1)
- Vehicle-track-soil interaction (1)
- Vibration measurement (1)
- Vollraum (1)
- Waves (1)
- Welded (1)
- Wellenausbreitung (1)
- Wellenausbreitung in der Tiefe (1)
- Wellengeschwindigkeit (1)
- Wind Energy (1)
- Wind Turbines (1)
- Windenergie (1)
- Windenergieanlagen (1)
- Zerstreute Achsimpulse (1)
- Zuggeschwindigkeit (1)
- building information modelling (1)
- structural health monitoring (1)
- structural integrity management (1)
- support structures (1)
- temperature (1)
Organisationseinheit der BAM
- 7.2 Ingenieurbau (82) (entfernen)
The shaft bearing capacity often plays a dominant role for the overall structural behaviour of axially loaded piles in offshore deep foundations. Under cyclic loading, a narrow zone of soil at the pile-soil interface is subject to cyclic shearing solicitations. Thereby, the soil may densify and lead to a decrease of confining stress around the pile due to microphenomena such as particle crushing, migration and rearrangement. This reduction of radial stress has a direct impact on the shaft capacity, potentially leading in extreme cases to pile failure. An adequate interface model is needed in order to model this behaviour numerically. Different authors have proposed models that take typical Interface phenomena in account such as densification, grain breakage, normal pressure effect and roughness. However, as the models become more complex, a great number of material parameters need to be defined and calibrated. This paper proposes the adoption and transformation of an existing soil bulk model (Pastor- Zienkiewicz) into an interface model. To calibrate the new interface model, the results of an experimental campaign with the ring shear device under cyclic loading conditions are here presented. The constitutive model shows a good capability to reproduce typical features of sand behaviour such as cyclic compaction and dilatancy, which in saturated partially-drained conditions may lead to liquefaction and cyclic mobility phenomena.
Abstract. Three measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results.
The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and forces.
The subject of damage localization is an important issue for Structural Health Monitoring (SHM) particularly in mechanical or civil structures under ambient excitation. In this paper, the statistical subspacebased damage localization method has been applied on a benchmark application, namely a 1/200 scale model of the Saint-Nazaire Bridge, which is a cable-stayed bridge located on the Loire River near the river’s mouth. The employed damage localization method combines data-driven features with physical parameter information from a finite element model in statistical tests, avoiding typical ill-conditioning problems of FE model updating. Damage is introduced in the mockup for cable failures on some of the 72 cables. The purpose of the experiment is to assess the capability of damage assessment methods to find a cable failure.
The Stochastic Dynamic Damage Locating Vector (SDDLV) approach is a vibration-based damage localization method based on both a finite element model of a structure and modal parameters estimated from output-only measurements in the damage and reference states. A statistical version of the Approach takes into account the inherent uncertainty due to noisy measurement data. In this paper, the effect of temperature fluctuations on the performance of the method is analyzed in a model-based approach using a finite element model with temperature dependent parameters. Robust damage localization is carried out by rejecting the temperature influence on the identified modal parameters in the damaged state. The algorithm is illustrated on a simulated structure.
Temperature variation can be a nuisance that perturbs vibration based structural health monitoring (SHM) approaches for civil engineering structures. In this paper, temperature affected vibration data is evaluated within a stochastic damage detection framework, which relies on a null space based residual. Besides two existing temperature rejection approaches – building a reference state from an averaging method or a piecewise method – a new approach is proposed, using model interpolation. In this approach, a general reference model is obtained from data in the reference state at several known reference temperatures. Then, for a particular tested temperature, a local reference model is derived from the general reference model. Thus, a well fitting reference null space for the formulation of a residual is available when new data is tested for damage detection at an arbitrary temperature. Particular attention is paid to the computation of the residual covariance, taking into account the uncertainty related to the null space matrix estimate. This improves the test performance, contrary to prior methods, for local and global damages, resulting in a higher probability of detection (PoD) for the new interpolation approach compared to previous approaches.
The subject of damage localization is an important issue for Structural Health Monitoring (SHM) particularly in mechanical or civil structures under ambient excitation. In this paper, the statistical subspacebased damage localization method has been applied on a benchmark application, namely a 1/200 scale model of the Saint-Nazaire Bridge, which is a cable-stayed bridge located on the Loire River near the river’s mouth. The employed damage localization method combines data-driven features with physical parameter information from a finite element model in statistical tests, avoiding typical ill-conditioning problems of FE model updating. Damage is introduced in the mockup for cable failures on some of the 72 cables. The purpose of the experiment is to assess the capability of damage assessment methods to find a cable failure.
The Stochastic Dynamic Damage Locating Vector (SDDLV) approach is a vibration-based damage localization method based on both a finite element model of a structure and modal parameters estimated
from output-only measurements in the damage and reference states. A statistical version of the Approach takes into account the inherent uncertainty due to noisy measurement data. In this paper, the effect of temperature fluctuations on the performance of the method is analyzed in a model-based approach using a finite element model with temperature dependent parameters. Robust damage localization is carried out by rejecting the temperature influence on the identified modal parameters in the damaged state. The algorithm is illustrated on a simulated structure.
Three measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and forces.
Superplasticizer and Shrinkage Reducing Admixture Dosages for Microfine Cement in Grout Systems
(2019)
Grouts have numerous applications including crack repair as maintenance in construction industries. Microfine cements are intensively used for high strength mortar and grout products. They are ideal for injection grouting in structural repair. Such grouts should have suitable rheological properties to be injectable, especially those used in repair and rehabilitation. The use of superplasticizers (SP) in these products is thus becoming increasingly crucial to achieve favorable workability and viscosity properties. A difficulty in such grouts is the plastic shrinkage due to finer particles used. It is thus necessary to determine optimum SP and shrinkage reducing admixture (SRA) dosages for a microfine cement based grout. In this study, a saturation dosage was decided from two Polycarboxylate ether (PCE) based SPs in relation to neat cement using slump flow and rheological parameters. A range of grout mixtures was formulated containing micro silica (MS) and fly ash (FA), and tested for suitable rheological and mechanical parameters. Based on the results, a grout mixture with MS and FA was selected to determine optimum SRA content. According to the results, a SP dosage of 3% by weight of neat cement is sufficient to achieve saturation. The grout material including MS and FA can produce comparable properties to neat cement grout. MS is found to improve compressive strength within the range considered, whereas a higher FA content provides favourable rheological properties. Finally, a SRA dosage of 4%, which could reduce the shrinkage by about 43% after 28d days, is determined for the grout system.
Within the presented research project, experimental and numerical investigations were performed to develop a thin-shelled, modular, mobile element system made of a micro-reinforced ultra-high-performance ductile concrete (DUCON®). Material parameters were experimentally determined to adapt the material model within the numerical analysis applying the Drucker-Prager relationship. Afterwards, for validation of the numerical models, quasi-static and high-velocity impact tests were performed on plate-like structures. Finally, a suitable geometry of transportable barrier elements will be designed, which provides a maximum of resistance against impact by a minimum of weight and a maximum of mobility.