Prediction of Deterioration of Concrete Bridges

In the early 20th century, the general idea was that concrete structures would never show deterioration. However, in the 1990s concrete structures showed an increase in number of cracks and area of spalling. Especially spalling of the concrete cover could create a harmful situation to the users. Spalling of the cover is caused by corrosion of...

Influence of admixtures and mixing efficiency on the properties of self compacting concrete: The birth of self compacting concrete in the Netherlands

Shear and Anchorage Behaviour of Fire Exposed Hollow Core Slabs

Hollow core (HC) slabs are made of precast concrete with pretensioned strands. These slabs are popular as floor structures in offices and housing. At ambient conditions, the load bearing capacity can be dominated by four different failure modes, i.e. flexure, anchorage, shear compression and shear tension. As the economic production process does...

Computational modelling of chloride ingress in concrete

Size effect of concrete and sandstone

A series of uniaxial tension experiments has been conducted to investigate the size effect on strength and fracture energy of concrete and sandstone. The experiments were carried on specimens of six different sizes in a scale range of 1:32. Depending on the material and the curing conditions a stronger or weaker size effect on the nominal...

Time-dependent fracture of cementitious materials

The response of cementitious materials is highly time dependent. On the one hand, it can lead to delayed collapse of structures fabricated of such materials. On the other hand, the time dependence is associated with the relaxation of peak stresses, which avoids, or postpones damage. A finite element formulation is presented for the analysis of...

Simulation of hydration and formation of structure in hardening cement-based materials

Second edition.

Experimental investigations on macro cell corrosion in chloride-contaminated concrete

Chloride-induced reinforcement corrosion in concrete is characterised by the action of so-called macrocells. The associated localised form of corrosion results from the strong electrochemical interaction between the relatively small pitting sites acting as anodes and the large passive steel areas acting as cathodes. The existence of macrocell...

Analysis of hygral induced crack growth in multiphase materials

In this paper a numerical model for simulating crack growth processes caused by moisture movement in a porous multiphase material like concrete is proposed. In the model, the material is schematized as a regular triangular network of beam elements. The meso-material structure of the material is projected on top of the lattice and different...

Fracture mechanics of concrete: Will applications start to emerge?

Fracture mechanics of concrete has developed into an active field of research in the past decades. It promises a rational solution technique to structural problems in reinforced concrete in the limit state. Numerical tools have been developed on the basis of fracture mechanics theories. The question to be addressed is how much of the early...

An Experimental Study of Shear Fracture and Aggregate Interlock in Cementbased Composites

In the present paper the results of an exploratory study with the recently developed biaxial tension/shear apparatus of the Stevin Laboratory of Delft University of Technology are presented. The apparatus is unique in the sense that square double-edgenotched concrete plates up to a size of 200 x 200 mm can be loaded in any combination of tension...

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...

Concrete under Impact Loading, Tensile Strength and Bond

Uniaxial impact tensile tests on plain concrete were carried out with the aid of Split Hopkinson Bar equipment with stress rates of up to 60000 N/mm2. s. Various concrete mixes were investigated under. dry and wet conditions. All the concretes showed an increase in strength with increasing stress rate. At very high stress rates the strength may...