In 2011, it seems that the one question that was on everybody's mind was: is self-healing of concrete possible? Even though it is not directly related to our project, we've been asking ourselves the same thing. Here is our suggestion:

And with that, the M3C4 team would like to wish everyone Marry Christmas and a happy New Year! Till next year!

Chloride ingress in cracked concrete

First simulation of chloride penetration in cracked concrete has been performed. A specimen (top) has been subjected to tension (below it-cracked elements after 15000 steps). Subsequently, it has been subjected to chlorides from the left side. Below are the chloride profiles at 30, 90, 180, 365, and 730 days, respectively. Till next time!

RCM test

Rapid chloride migration testing is increasingly used in practice to assess the chloride resistance characteristics of a concrete mix. It is fast and simple, and can be performed with no fancy equipment whatsoever. Standardized as NT BUILD 492 in Scandinavia, it is also increasingly popular in the Netherlands. But, is there a faster way of testing? Well, of course there is: a numerical simulation! If we could simulate the test, different concrete mixes could be tried and the best one chosen. The first simulation of the test is here. Enjoy!

Here is the comparison of our simulations with some experimental data from the literature:

Wedge splitting test

Wedge splitting test is a simple test often used in fracture mechanics. Some trial tests were perfomed in the Microlab last week. Here is the result:

Courtesy of our very own (official Microlab) photography maestro CA:

Fracture simulation Brazilian splitting

Here is a video of (tensile) stresses which develop in a homogeneous specimen during the Brazilin splitting, predicted by the lattice model. Enjoy!

CTC

The specimens made for the RILEM CTC experiment are now running. The figure shows the open circuit potential of the specimens after 2 weeks. Results seem promising. We'll keep in touch...

Meso-scale model

Concrete is a composite material containing several phases. These phases do not contribute equally to the chloride penetration, since some are more permeable than the others. Since this could be quite challenging to test in the lab, numerical simulation can give us some insight. In the video you can see, first, the concrete meso-structure (mortar, aggregate, ITZ), followed by the penetration of chlorides in time. Enjoy!

Chloride, AZ

Chloride, AZ from Secret Ingredient Co. on Vimeo.

Chlorides are so relevant to our daily life, that a town in Arizona, US is named after them.

Enjoy!

New modelling results

Our simulation results look better and better. You can see the progress here:

Concrete Solutions 2011

The M3C4 project contributed to the proceedings of the 4th International Conference on Concrete Repair - Concrete Solutions 2011. The conference was held on September 26 to 28th 2011 in the city of Dresden, Germany. New contacts, interesting feedback and a lot of fun are the result of such conference.

Until next time,

In time, chloride ions penetrate the concrete cover. When a sufficient amount reaches the reinforcing steel, corrosion commences. In order to control the process, we should be able to model it. First results can be seen in the video.

Users Committee Meeting M3C4

On Tuesday, 20th of September, the first users committee meeting of the M3C4 project was held in Delft. Progress has been presented to representatives of the industry and the STW. A discussion was sparked and ideas have been exchanged. A lot of questions were left unanswered for the next time... Till then!

Youtube as a knowledge base

Did you know that youtube has a lot of videos dedicated to research and science? Next time you need something, try searching for it there instead using google! Some examples of videos about thin section making:

http://www.youtube.com/watch?v=VB_QLUP6Ft0

http://www.youtube.com/watch?v=ZftQDf04E2M

Looks familiar? This is the very machine available in our lab! Enjoy!

Final batch CTC

On Friday August 26th the final batch of CTC specimens was carried out. So far, the team is ready to cure and then expose the specimens. The cutting of the specimens is programmed for the beginning of September and results seem promising. We'll keep it updated...

Our efforts are finally starting to pay off... First simulations have been performed for the steady-state diffusion, and the figure shows the result. More coming soon!

Cutting of specimens CTC

The first trials of the specimen cutting for the CTC project were carried out with success. These trial specimens were meant to try the cutting procedure before using the real CTC specimens.

Here are also some images of the final results!

CTC specimens

On July 4th, the first series of specimens cast according to the recommendation of RILEM TC-CTC "Chloride threshold concentration" were cast by the PhD members of the team. The overall result did not showed any problems regarding to the mix design or the casting procedure. Any researcher or research lab interested in this Rilem committee is welcome to contact any of the team members for discussion about the mix design or the future work. Until next time,

Life's so hard...

Life as a PhD student is not easy... A lot of hard work is involved!

Concrack 2 Workshop

A second workshop dedicated to control of cracking in reinforced concrete structures, titled Concrack 2, was held in Paris, from 20-22 of June. The M3C4 team presented the results of their simulation, and discussed it with the other participants. Further work is expected to make the simulation results more "realistic", and thus closer to measurements. Fruitful discussions with other participants on the topic of concrete modelling are apreciated. Till next time!

Members of the M3C4 team participated in the Concrete Microscopy Course 2011 (16-20 May), organized by Microlab, TU Delft. Lecturers from the Microlab, as well as guest lecturers from abroad (Mr. Per Hagelia of the Norwegian Public Roads Administration and Dr. Karl Peterson of University of Toronto) made sure that participants learned as much as possible about microscopy and its use in concrete research and practice. We will surely use the knowledge extensively in our research!

Next course is already in planning, and all info can be found at: www.cmc.tudelft.nl.

IS2C kick-off Woerden

On Thursday, 19th of May 2011, participants of the IS2C program have met in Woerden for the official kick-off of the program. All of the projects were represented by posters, so was of course the M3C4 project! An introduction by the program committee was followed by a workshop and discussions amongst the participants. Industry representatives were present and actively involved in the discussion. Cooperation between related projects is now envisioned and in the works!

Rob Polder gave his Professor speech

Prof. Rob B Polder did his Professor inaugural speech on May 13th 2011. He was joined by family, friends and colleagues in TU Delft's AULA. Pictures will come soon...

- J

Cracking of specimens

The M3C4 team has carried out the first set of trials for cracking concrete. The results are satisfactory and the overall outcome of the experiment is promising. The next step will include casting more cubes with different concrete compositions and start the curing.
Let the cracking begin!

- J

Concrete cores from the sea

The team has just had two concrete cores delivered by one of our industrial partners, BAM Infraconsult. The cores have been taken out of massive concrete blocks, which had been laid at sea for a number of years. Being exposed to these harsh environmental conditions for so long, their investigation promises to be very interesting!

CTC project about to start!

The instrumentation of the tank for CTC project is done. The team is about to start working on concrete specimens according to the recommendation of RILEM CTC committee. More details regarding the process of the project will follow.

- J

Rob Polder on your screen!

Check out the recorded presentation of Prof. Rob B. Polder on Cathodic Protection

http://videolectures.net/asfs09_polder_cpelcb/

Wanting more?

Check out the discussion:

http://videolectures.net/asfs09_jacob_dmp/

Madrid - RILEM PhD Workshop

A PhD meeting was organized by RILEM members, C. Andrade and J. Gulikers, taking place in Madrid, Spain on the 19th -November. Thanks for the opportunity, the exciting discussion and until next time!

New year - new blog!

Hi all,

With the beginning of year 2011 the team of STW's project M3C4 "Chloride ingress in cracked concrete" has started a new blog. In this site, you'll find the now-and-then experience of the research. Feel free to give any feedback to the team members.

The team,