Inst. Bauingenieurwesen

169 Items

Recent Submissions
Study on the production of core-shell structured lightweight aggregate by cold-bonding agglomeration process and its utilization in concrete

Tajra, Feras (2020)

Lightweight aggregate concrete has been widely used in different construction applications due to its advantageous characteristics such as low density, low thermal conductivity and good durability properties. Compared to conventional concrete, lightweight aggregate concrete is made by replacing normal weight aggregate with lightweight aggregate, which is taken from natural resources or produced...

Electronic supplemental material

Simons, Franz (2020-01-31)

This is the electronic supplemental material to the doctoral thesis "A robust high-resolution hydrodynamic numerical model for surface water flow and transport processes within a flexible software framework". The full source code of the Hydroinformatics Modeling System (hms) is available at TU Berlin GitLab. Access to the GIT repository is granted by the Chair of Water Resources Management and ...

A robust high-resolution hydrodynamic numerical model for surface water flow and transport processes within a flexible software framework

Simons, Franz (2020)

In water resources management computer simulations and numerical methods have become a more and more important tool for supporting decisions. They enable the understanding of complex relationships in the hydrological cycle and predictions about future development. This thesis describes the development of a numerical modeling software which allows the integrated simulation of surface water flow...

A three-dimensional two-phase model for flow, transport and mass transfer processes in sewers

Teuber, Katharina (2020)

Sewer networks are one major pillar of modern cities’ infrastructure. Their functionality ensures the transport of wastewater to the sewage treatment plant and the transport of rainwater from residential areas. Damages to sewers cause infiltration and exfiltration and at the same time high costs for rehabilitation. The formation of hydrogen sulphide (H2S) represents a risk factor for the condit...

Investigation of the fluidised zone in deep vibrocompaction

Wotzlaw, Moritz (2019-09)

Deep vibrocompaction is an established method for the improvement of loose sandy soils using deep vibrators. In a basic modelling concept, the area of the ground influenced by the vibrator is subdivided into three concentric cylindrical zones. According to that model, the compaction occurs only in some distance to the vibrator, since the acceleration amplitudes in the vicinity, the so-called fl...

Numerical evaluation of the soil behavior during impact driving of pipe-piles

Daryaei, Reza ; Bakroon, Montaser ; Aubram, Daniel ; Rackwitz, Frank (2019-09)

During the impact driving of pipe-piles, the soil is influenced in different ways including the void ratio, stress distribution, and plugging formation. Such effects may play an important role in structural design criteria such as the pile’s lateral support provided by the soil. Hence, this work is focused on investigating the change in the mechanical characteristics of the soil during impact d...

Numerical evaluation of the pipe-pile buckling during vibratory driving in sand

Bakroon, Montaser ; Daryaei, Reza ; Aubram, Daniel ; Rackwitz, Frank (2019-09)

The buckling of steel pipe piles during vibratory driving is numerically studied using the Multi-Material Arbitrary Lagrangian-Eulerian (MMALE) method. This method handles the large soil deformations that occur during pile driving and other geotechnical installation processes. The Mohr-Coulomb and an elastic-perfectly plastic material model are used to model the soil and the pile mechanical beh...

Photocatalytic Activity and Mechanical Properties of Cements Modified with TiO2/N

Janus, Magdalena ; Mądraszewski, Szymon ; Zając, Kamila ; Kusiak-Nejman, Ewelina ; Morawski, Antoni W. ; Stephan, Dietmar (2019-11-14)

In this paper, studies of the mechanical properties and photocatalytic activity of new photoactive cement mortars are presented. The new building materials were obtained by the addition of 1, 3, and 5 wt % (based on the cement content) of nitrogen-modified titanium dioxide (TiO2/N) to the cement matrix. Photocatalytic active cement mortars were characterized by measuring the flexural and the co...

Accident Rate as a Measure of Safety Assessment in Polish Civil Engineering

Cieslewicz, Wieslawa ; Araszkiewicz, Krystyna ; Sikora, Pawel (2019-10-30)

Civil engineering is characterised by high volatility with respect to working conditions, which are the source of many threats to worker life and health and contribute to high accident rates. The purpose of this paper is to analyse and evaluate the phenomenon of accidents in Polish civil engineering and define the direction of changes that should occur in the safety area. The studies included i...

Is the Hyporheic Zone Relevant beyond the Scientific Community?

Lewandowski, Jörg ; Arnon, Shai ; Banks, Eddie ; Batelaan, Okke ; Betterle, Andrea ; Broecker, Tabea ; Coll, Claudia ; Drummond, Jennifer ; Gaona Garcia, Jaime ; Galloway, Jason ; Gomez-Velez, Jesus ; Grabowski, Robert ; Herzog, Skuyler ; Hinkelmann, Reinhard ; Höhne, Anja ; Hollender, Juliane ; Horn, Marcus ; Jaeger, Anna ; Krause, Stefan ; Löchner Prats, Adrian ; Magliozzi, Chiara ; Meinikmann, Karin ; Mojarrad, Brian ; Mueller, Birgit ; Peralta-Maraver, Ignacio ; Popp, Andrea ; Posselt, Malte ; Putschew, Anke ; Radke, Michael ; Raza, Muhammad ; Riml, Joakim ; Robertson, Anne ; Rutere, Cyrus ; Schaper, Jonas ; Schirmer, Mario ; Schulz, Hanna ; Shanafield, Margaret ; Singh, Tanu ; Ward, Adam ; Wolke, Philipp ; Wörman, Anders ; Wu, Liwen (2019-10-25)

Rivers are important ecosystems under continuous anthropogenic stresses. The hyporheic zone is a ubiquitous, reactive interface between the main channel and its surrounding sediments along the river network. We elaborate on the main physical, biological, and biogeochemical drivers and processes within the hyporheic zone that have been studied by multiple scientific disciplines for almost half a...

Literature review of optimization based decision model for disaster recovery planning of transportation network

Zamanifar, Milad ; Hartmann, Timo (2020-08-30)

The purpose of this study is to analysis optimization-based decision-making models for the problem of Disaster Recovery Planning of Transportation Networks (DRPTN). In the past three decades, seminal optimization problems have been structured and solved for the critical and sensitive problem of DRPTN. The extent of our knowledge on the practicality of the methods and performance of results is h...

Konzeption eines Organisations- und Kooperations-Leitsystems mit anreizbasierten Vergütungselementen zur Verbesserung der Kooperation, der Kommunikation und der Termineinhaltung in Bauprojekten

Giebelhausen, John-Albert (2019)

Störungen im Planungs- und Bauablauf sind bei der Abwicklung von Bauprojekten in Deutschland ein ungewolltes, jedoch regelmäßig anzutreffendes Phänomen. Die Folgen sind zumeist erhebliche Überschreitungen des ursprünglich geplanten und vereinbarten Terminrahmens und dadurch bedingte Mehrkosten. Bisher können die herrschenden Probleme weder durch individualvertragliche Regelungen auf Basis des...

Relating Ettringite formation and rheological changes during the Initial cement hydration

Jakob, Cordula ; Jansen, Daniel ; Ukrainczyk, Neven ; Koenders, Eddie ; Pott, Ursula ; Stephan, Dietmar ; Neubauer, Jürgen (2019-09-12)

In order to gain a deeper understanding of the rheological development of hydrating ordinary Portland cement (OPC) pastes at initial state, and to better understand their underlying processes, quantitative X-ray diffraction (XRD) analysis and rheological measurements were conducted and their results combined. The time-dependent relation between phase development and flow behavior of cement past...

Influence of Nanosilica on Mechanical Properties, Sorptivity, and Microstructure of Lightweight Concrete

Abd Elrahman, Mohamed ; Chung, Sang-Yeop ; Sikora, Pawel ; Rucinska, Teresa ; Stephan, Dietmar (2019-09-21)

This study presents the results of an experimental investigation of the effects of nanosilica (NS) on the strength development, transport properties, thermal conductivity, air-void, and pore characteristics of lightweight aggregate concrete (LWAC), with an oven-dry density <1000 kg/m3. Four types of concrete mixtures, containing 0 wt.%, 1 wt.%, 2 wt.%, and 4 wt.% of NS were prepared. The develo...

Über ein elastoplastisches Stoffgesetz für zyklisch beanspruchten Sand

Carow, Christian ; Rackwitz, Frank ; Savidis, Stavros (2017-07-21)

Die numerische Simulation aktueller Problemstellungen in der Geotechnik erfordert Stoffgesetze, die das Spannungs‐Dehnungsverhalten von Sand realitätsnah beschreiben. In Bezug auf monotone Lasten sind mit bestehenden Modellierungsansätzen bereits sehr gute Ergebnisse zu erzielen. Das Materialverhalten bei zyklischer Beanspruchung ist jedoch außerordentlich komplex. Selbst die derzeit leistungsf...

Characterization data of reference cement CEM I 42.5 R used for priority program DFG SPP 2005 “Opus Fluidum Futurum – Rheology of reactive, multiscale, multiphase construction materials”

Lu, Zichen ; Haist, Michael ; Ivanov, Dimitri ; Jakob, Cordula ; Jansen, Daniel ; Leinitz, Sarah ; Link, Julian ; Mechtcherine, Viktor ; Neubauer, Jürgen ; Plank, Johann ; Schmidt, Wolfram ; Schilde, Carsten ; Schröfl, Christof ; Sowoidnich, Thomas ; Stephan, Dietmar (2019-10-22)

A thorough characterization of starting materials is the precondition for further research, especially for cement, which contains various phases and presents quite a complex material for fundamental scientific investigation. In the paper at hand, the characterization data of the reference cement CEM I 42.5 R used within the priority program 2005 of the German Research Foundation (DFG SPP 2005) ...

Lagrange-Euler Formulierungen in der Bodenmechanik

Savidis, Stavros A. ; Aubram, Daniel (2015-04-17)

Bodenmechanische und geotechnische Problemstellungen werden häufig durch große Materialverformungen und andere damit einhergehende Phänomene gekennzeichnet. Bei deren Modellierung stoßen die klassische Bodenmechanik und die traditionelle Finite Elemente Methode basierend auf der Lagrange Formulierung an ihre Grenzen. In dem Beitrag werden die kontinuumsmechanischen Grundlagen einer verallgemein...

Vibro-Injection Pile Installation in Sand: Part II—Numerical and Experimental Investigation

Savidis, Stavros A. ; Aubram, Daniel ; Rackwitz, Frank (2015-06-12)

In Part 1 of this series of papers a macroscopic two-equation (two-field) reduced model for the mechanics of the multi-material flow associated with vibro-injection pile installation in saturated sand was derived. Here we employ this model to develop a so-called multi-material arbitrary Lagrangian-Eulerian (MMALE) method. MMALE avoids the disadvantages of the classical approaches in computation...

Vibro-Injection Pile Installation in Sand: Part I—Interpretation as Multi-material Flow

Aubram, Daniel ; Rackwitz, Frank ; Savidis, Stavros A. (2015-06-12)

The installation of vibro-injection piles into saturated sand has a significant impact on the surrounding soil and neighboring buildings. It is generally characterized by a multi-material flow with large material deformations, non-stationary and new material interfaces, and by the interaction of the grain skeleton and the pore water. Part 1 in this series of papers is concerned with the mathema...

Theory and Numerical Modeling of Geomechanical Multi-material Flow

Aubram, Daniel ; Savidis, Stavros A. ; Rackwitz, Frank (2015-10-29)

Multi-material flow describes a situation where several distinct materials separated by sharp material interfaces undergo large deformations. The research presented in this paper addresses a particular class of multi-material flow situations encountered in geomechanics and geotechnical engineering which is characterized by a complex coupled behavior of saturated granular material as well as by ...