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Testing the Test: Water Absorption with RILEM Tubes

The Construction Specifier

August 1, 2013

RILEM tubes can be used to assess a substrate’s resistance to water absorption, to compare the absorption before and after treatment with a water repellent, and to evaluate the durability of a repellent by periodically measuring absorption. Although widely used by the construction industry, there is currently no industry standard available describing exactly how to perform the test. Small changes in the testing procedure may lead to different results, including how to attach the tube, how to fill it, and at which intervals to perform the readings. Standardization would improve the uniform interpretation of results.

If you are interested in reading the full article written by Adrian Saldanha (UT Austin) and Doris Eichburg (Building Diagnostics, Inc)  please go to:  http://www.kenilworth.com/publications/cs/de/201308/index.html at ‘Rethinking the Rilem Test’

 

Off to the Real World!!!

Our lab at CMRG/CDC is getting considerably smaller this Summer.  Numerous students graduated this May, including Zeynep Basaran, Rachel Cano, Reid Markus, Sri Ramya Duddukuri Nair, Sarah Taylor Lange,  Trevor Williamson, and Jose Zuniga.  It is very sad to see them all go, however it is very exciting to know of the wonderful things they will accomplish in their very bright futures.

From left to right:  Sri Ramya Duddukuri Nair, Zeynep Basaran and Rachel Cano

 Sri Ramya Duddukuri Nair’s Plans After Graduation

After I defend my PhD this August, I’m going to work in the Petroleum and Geosystems Dept. at UT Austin as a Research Associate. I’ll be working under Prof. Eric van Oort in their zonal isolation lab. I’m really excited to learn about issues in oil/gas cementing and to work on ways to improve current cementing techniques.

Zeynep Basaran’s Plans After Graduation

Traveling back to Istanbul, Turkey, my original home. I am planning to work as a faculty in a research oriented University.

Rachel Cano’s Plans After Graduation

I’ll be working as an engineer for TxDOT in the concrete lab at their Cedar Park offices. I just passed the FE and I’ll be registered as an EIT soon.

Understanding Why Doors Leak!

Findings from a durability lab

by Adrian Gerard Saldanha and David H Nicastro, PE

Leaking exterior doors are a common problem affecting building owners and tenants, causing property damage, and requiring expensive repairs.  Designers and builders are aware of the issue.  Nevertheless, they continually struggle to prevent water infiltration through this fundamental building element.

It may seem obvious to recommend collaboration of all stakeholders to achieve project success, but for exterior doors it is essential.  Issues related to waterproofing, accessibility, and aesthetics compete with each other, requiring a comprehensive, balanced approach to achieve a leak-free, attractive, and code compliant envelope.  Ultimately, it is failure to collaborate that leads to fingerpointing when the doors leak.

Adrian Gerard Saldanha is completing his master’s degree in construction engineering and project management at the University of Texas at Austin (UT)  He is a graduate research assistant in The Durability Lab – a testing center at UT established by Building Diagnostics Inc., to study the durability of building components, identifying factors causing premature failure. David H. Nicastro, PE, is the founder of Engineering Diagnostics Inc. and Building Diagnostics Inc. – firms specializing in the investigation of problems with existing buildings, designing remedies for those problems, and resolving disputes which arise from them.  You can view the entire article at:  http://www.kenilworth.com/publications/cs/de/201305/files/52.html

The Construction Specifier

May 2013

 

Concrete Sustainability Requires Coordinated Research into Hydration, Believes Expert

While the metallurgical and semiconductor industries have benefited from a deeper understanding of chemical processes that underlie productivity improvements, the concrete industry is falling behind.

In large part, that can be attributed to a lack of thorough understanding of the chemical processes involved in the hydration of portland cement, says Maria Juenger, associate professor, University of Texas at Austin.

Juenger says that miracle metals, polymers, pharmaceuticals and semi-conductors were developed through an understanding of chemical kinetics — the study of rates and mechanisms of chemical reactions and of the factors on which they depend. By mastering kinetics, concrete producers can also maximize sustainability.

“Using kinetics, we can look at the life cycle performance of our concrete,” she says.

“With that understanding we can optimize the durability, optimize the cost and minimize the environmental impact.”

She notes that, while some research has promoted advances in concrete technology, the industry lacks any sort of coordinated research effort that would lead to a thorough understanding of the underlying chemistry behind hydration.

“Ultimately, a more coordinated effort needs to be assembled that enables research teams to focus on specific tasks identified within a roadmap for developing a comprehensive description of cement hydration rather than individual efforts being spent on isolated tasks,” says Juenger.

A roadmap for coordinated research was developed at the International Summit on Cement Hydration Kinetics and Modeling held at Laval University in 2009 and championed by Joseph Biernacki, professor of Chemical Engineering at Tennessee Technological University, among others.

“As engineers the means we have at our disposal are primarily composition and processing,” she says.

“The vision Joe has is to optimize the materials going in on the composition end — the admixtures, the cement, the aggregate and water — and the processing of those materials to achieve the desired end and not look at the process in between as a black box. Let’s try to engineer these hydration processes in the middle that are affecting our setting time and durability in a way that isn’t simply trial and error but engineered.”

Juenger notes that concrete mixtures employing fibres, admixtures that control shrinkage and super plasticizers are no longer cutting edge technology.

“Those are not emerging technologies,” she says.

“Those are proven technologies. Right now we’re up against a wall. If scientists don’t understand the chemical process, we can’t manipulate them. Our key to make dramatic changes in the way concrete performs is to make dramatic changes in the way that we understand concrete.”

The industry is also failing to take advantage of the most sophisticated tools available for materials research, she says. That, however, is changing as concrete researchers begin to employ such tools as nano-x-ray tomography and vertical scanning interferometry, which examine chemical processes at a minute scale.

Juenger says that effective molecular modeling is also essential to achieve the type of understanding necessary to make breakthroughs.

“We don’t yet have universal software tools or a universally accepted platform for modeling,” she says.

“We have a lot of separate platforms that can’t easily be combined in a cohesive manner. We’re getting closer, but we’re not there yet.”

Juenger spoke at the Fall 2012 convention of the American Concrete Institute held in Toronto.

Written by Peter Kenter

Daily Commercial News

http://www.dcnonl.com/article/id52681/–concrete-sustainability-requires-coordinated-research-into-hydration-believes-expert

 

ACerS Cements Division Annual Meeting

The ACerS Cements Division held its annual meeting at the University of Texas at Austin on June 10-12, 2012.  The meeting was themed “3rd Advances in Cement-based Materials:  Charactarization, Processing, Modeling and Sensing,” and was organized by Zach Grasley, Dr. Maria Juenger and Jeff Chen in coordination with the Center for Advanced Cement-based Materials.  Many of Dr. Juenger’s students attended and participated in the meeting; sharing posters of their research and presenting research findings to the attendees.

From left to right:  Zeynep Basaran, Lisa Burris, Saamiya Seraj, Rachel Cano and SriRamya Duddukuri Nair

From left to right:  Zeynep Basaran, Saamiya Seraj, Dr. Maria Juenger, Sarah Taylor-Lange, and SriRamya Duddukuri Nair

Two of Dr. Juenger’s former students also attended and presented at this years meeting.

Mr. Craig Hargis

 

 Dr. Irvin Chen

 

Age-Old Recipe for Concrete is Water, Cement, Sand, and Rocks

Dr. Maria Juenger and Katherine ‘Katy’ Aughenbaugh were participants in a podcast which is part of the Sustainable Design Radio Program. This program is a collaboration between IEEE Spectrum and the National Science Foundation. You can hear the podcast at the following Sustainable Design for the Future

ACI Central Texas Chapter scholarship winners

The following students won ACI Central Texas Chapter Scholarships, YAY!!!! Congratulations!!

Aaron Woods

Karla Kruse

SriRamya Duddukuri Nair

Texas officials are preparing to spend as much as $20 million to redo a state-owned building that began showing signs of major structural problems only a decade after it was built.

The walls of the Robert D. Moreton Building in Central Austin, which cost $8 million to construct 22 years ago, are now crumbling, cracking and separating — and the massive concrete panels that cover the building’s exterior are at risk of eventual failure.

Engineers and architects, so concerned by its condition, considered demolishing the structure but deemed that too expensive, the American-Statesman has found.

“The engineers have been very clear that this is a serious problem,” said Peter Maass, director of project management for facilities design and construction for the Texas Facilities Commission, which manages the structure. “It is certainly a disturbing kind of thing. You don’t expect buildings to do this.”

State employees began noticing possible structural problems at least a decade ago. Architects have since traced the problems to the expansion and cracking of the concrete panels, weighing more than 50,000 pounds, that form the building’s shell.

More than 500 people work in the seven-story building on the northeast corner of 49th Street and Grover Avenue and will have to relocate during the renovation, expected to take two years or more.

State officials said they hope repairs will begin next spring.

The state will pay for the work and associated expenses and has not yet sought any reimbursement from the building’s original contractor. A state-commissioned study blamed curing temperatures when the panels were made. The company that built the structure, E.E. Reed Construction, remains in business in Houston.

An E.E. Reed spokeswoman declined to comment.

Kay Molina, the facility commission’s general counsel, said any decision about whether to seek money from E.E. Reed would be “made in conjunction with the office of the attorney general” and that “is all I can state publicly at this time regarding our legal position.” Officials at the attorney general’s office referred calls to Molina.

Engineers found last year in a study — recently obtained through the Texas Public Information Act — that the problems create such a risk of falling chunks of concrete that officials have set up covered walkways to the building’s entrances and ringed its perimeter with chain-link fencing.

Carrie Williams, spokeswoman for the Texas Department of State Health Services, whose offices are in the building, said that “there are some safety concerns that we need to address. We aren’t wearing hard hats or anything like that, but there is work to be done.”

Among the 35 state-owned office buildings, the Moreton building falls near the middle in age.

The average state office building is 33 years old, and about 12 across the state are older than Moreton.

Records obtained by the American-Statesman show that the state spent about $8 million in 1989 to build the office tower, which is named for a vice president emeritus and special assistant to the president of the University of Texas M.D. Anderson Cancer Center who died in 1992.

Today, estimates show that the repair will cost from $12 million to $15 million — excluding items such as architectural designs and moving expenses for employees — while the state would spend up to $32 million for a new structure.

Engineers in 2001 first cited concerns about the building’s outside panels, according to a 37-page report last year by Tom Green & Company Engineers Inc. But officials said the earlier review did not fully identify the scope of the issues.

More recently, crews have closely studied the outside “skin” of the building and found that the panels are suffering from a chemical delayed reaction in the curing process, “causing movement from the panels from their installed position,” the report last year said. The shifts have caused problems both inside and outside.

“The reaction has been determined to be approximately 10 percent complete, resulting in an expected further reaction to a point of partial or complete failure of the panels, each of which weighs in excess of 50,000 pounds,” the report said.

That report did not place blame, but a separate study the state commissioned in 2008 cited concrete temperatures that were too hot during curing when the panels were made.

On a recent tour of the building for the American-Statesman, Maass pointed out multiple random cracks that extend several feet on the outside panels. In offices inside, he noted large cracks extending down walls and showed how some window walls have separated from adjacent interior walls, creating significant gaps.

State officials have spent about $250,000 for what they have said were short-term repairs, including covering the panels with a sealant to minimize the risk of cracking.

But the most recent study warned that “panel deterioration is on-going, and periodic maintenance is not a solution. Near term skin replacement, or abandonment of the building and nearby site is necessary.”

In a recent memo to employees, David Lakey, commissioner for the state health services department, said officials have begun exploring where staff will go and that he realizes the move will interrupt daily commutes and create possible child care concerns for working parents.

“We hope to make this transition as smooth as possible,” he said.

Article Written by: Tony Plohetski, Austin American-Statesman

Doctoral Student Receives Best Poster Award

Katherine Gustashaw, a doctoral student in the structural engineering, mechanics, and materials program, won the best poster award at the 13th International Congress on the Chemistry of Cement held in Madrid, Spain July 3-8, 2011. Katy, along with Ryan Chancey (UT PhD 2008), Paul Stutzman from NIST, and Maria Juenger were honored for their poster “Quantitative Characterization of Fly Ash Reactivity for Use in Geopolymer Cements”.

Theirs was one of 100 posters entered at the conference, which was attended by over 900 people. Only two other awards were handed out: best presentation, and best short presentation.

Katy received her MS degree from UT Austin in spring 2009, and is supervised by Dr. Maria Juenger.

[The ACerS] meeting organizers recognized six poster presenters [one of which is our very own, Sarah Taylor Lange] for the exceptional quality of their work. Her winning poster is “Concrete Constituent Contributions to Indoor Radon Emissions.”

Meeting co-chair Jeff Chen, left, with poster winners Brown, Jayapalan, Stynoski and Lange. Credit: P. Wray, ACerS.

Posted by The American Ceramics Society

http://ceramics.org/ceramictechtoday/2011/07/26/cements-division-announces-officers-fellows-brunauer-award-and-posters-winner/