Impact of Temperature Cycling Conditions on Board Level Vibration for Automotive Applications

Board level vibration testing is a commonly used method to predict the solder joint reliability of surface-mounted components seated onto printed circuit boards (PCB). Current board level vibration test methods are mainly developed from a solely mechanical stress application standpoint. This makes such stress tests one dimensional in nature...

A strategy for material characterisation of multi-wythe masonry Infrastructure: Preliminary study

The present work aims at providing insights on the material characterization of multi-wythe masonry infrastructure, in particular exploring a through-thickness effect of mechanical properties and benchmarking the core testing as an efficient slightly-destructive testing method. An experimental campaign was carried out to characterize shear,...

Mechanical Characterisation of Multi-Wythe Masonry Bridge in the City of Amsterdam

This paper presents the results of an experimental campaign carried out to characterise the mechanical properties of multi-wythe masonry infrastructure in the city of Amsterdam. Samples were extracted from a 1.2 m thick bridge’s pillar constructed in 1882. For the characterisation of shear and compressive properties of masonry, tests on cores...

A review of printing strategies, sustainable cementitious materials and characterization methods in the context of extrusion-based 3D concrete printing

This paper aims to provide a systematical review of the available printing strategies, sustainable cementitious materials and characterization methods for extrusion-based 3D concrete printing (3DCP). The printing strategies, consisting of printing setup, process, and material requirements, were summarized initially. In the material aspect,...

Experimental and numerical study of bending-induced buckling of stiffened composite plate assemblies

Despite their importance in benchmarking numerical simulations, buckling tests still feature compromises between component-level and high-fidelity large-scale tests. For example, compression-induced buckling tests cannot capture the through-thickness or span-wise stress gradients in wing skins. Consequently, the results obtained often require...

Material characterisation of existing masonry: A strategy to determine strength, stiffness and toughness properties for structural analysis

Understanding the behaviour of unreinforced masonry (URM) structures requires in-depth insight into the mechanical properties of its constituents and their interaction under compression, tension, and shear loading. As a result, a complete picture of masonry characteristics, accounting for its full nonlinear response and its statistical...

Core testing method to assess nonlinear behavior of brick masonry under compression: A comparative experimental study

This study investigates the applicability of the core testing method to assess the complete nonlinear behavior of masonry in compression. A comparative experimental approach was adopted performing compressive tests on cores and companion wallets. Via a correlation study on seven objects, including literature data, a one-to-one correlation for...

An analysis of compressive strength development in CSEB and optimizing testing methods

After the earthquake in 2015 that struck Nepal, students of the Delft University of Technology commenced the multidisciplinary project program “Shock Safe Nepal”. This report describes the effort of the sixth group of students who travelled to Nepal. Following conclusions and specific recommendations of Team 5, the present research has one main...

New test methods to verify the performance of chemical injections to deal with rising damp

The injection of chemical products, meant to penetrate in the capillaries of the materials composing an affected wall, is perhaps the most diffused method to deal with rising damp. The majority of these chemical products are hydrophobic treatments; they can be either solvent-based or (increasingly) water-based. Traditionally, these products...

Setup for EMI Shielding Effectiveness Tests of Electrically Conductive Polymer Composites at Frequencies up to 3.0 GHz

Conductive polymer composites have been receiving increased interest both from the scientific community and industry with a special focus on electromagnetic interference (EMI) shielding applications. In this paper, we present the design, EM wave simulation, and validation through S-parameters measurements of an EMI shielding effectiveness (SE...

Evaluating the Infiltration Performance of Eight Dutch Permeable Pavements Using a New Full-Scale Infiltration Testing Method

Permeable pavements are a type of sustainable urban drainage system (SUDS) technique that are used around the world to infiltrate and treat urban stormwater runoff and to minimize runoff volumes. Urban stormwater runoff contains significant concentrations of suspended sediments that can cause clogging and reduce the infiltration capacity and...

Optimization of flowable concrete for structural design: Progress report of fib task group 8.8

With the tendency to apply concrete with a higher workability and the use of new concrete components more options are available to design concrete. New concrete types like self-compacting concrete (SCC), ultra-high performance fibre reinforced concrete (UHPFRC) and high performance fibre reinforced cementitious composite (HPFRCC) also require...

Self-healing coatings for textile

Self-healing materials have the capabillity to repair (in an early stage) damage, that would finally lead to material failure. This repair or self-healing occurs with the help of a minor external stimulus or autonomously. Depending on the type of application one or the other is more interesting. Nature is the major source of inspiration for his...

Evaluation of Spreading and Effectiveness of Injection Products against Rising Damp in Mortar/Brick Combinations

Rising damp is one of the most recurrent and well-known hazards to existing buildings and monuments. Several types of intervention exist to tackle the problem. Among these, the creation of a damp-proof course against capillary rise by means of injection of chemical products is one of the most diffused methods, thanks to the relatively easy and...

Aero- and Hydrodynamic Performance Analysis of a Speed Kiteboarder: Breaking the World Speed Sailing Record

Motivation: Speed sailing can be seen as the ultimate challenge for a sailing craft. Kiteboarders have recently shown to be capable of extremely high sailing speeds using a relatively cheap and simple combination of a kite and a board. They proved to be the world’s fastest sailing crafts during a record attempt in October 2008, in September 2009...

Experimental demonstration of wind turbine noise reduction through optimized airfoil shape and trailing-edge serrations

The objective of the European project DATA (Design and Testing of Acoustically Optimized Airfoils for Wind Turbines) is a reduction of trailing-edge (TE) noise by modifying the airfoil shape and/or the application of trailing-edge serrations. This paper describes validation measurements that were performed in the DNW-LLF wind tunnel, on a model...

Garteur compression behaviour of advanced CFRP

The susceptibility of currently used CFRP to impact damage has stimulated the development of improved composites. This new generation of composites usually shows increased toughness and damage tolerance as well as improved tensile performance. This is generally not matched, however, by a similar improvement in compressive properties which then...

Fatigue Failure of Concrete in Tension

Concentric tensile and flexural tensile fatigue tests were carried out on plain concrete specimens. The effects of pulsating tensile loadings as well as of alternating tensilecompressive loadings were studiep. The results of the constant-amplitude tests have been presented in S-N diagrams and a Goodman diagram. From these results it emerged that...