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Wednesday, Feb. 19, 1997

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Team develops simple test for early detection of failing concrete
Peña confirmation vote delayed
Tri-Lab Day at the Legislature
Lab signs agreement with Microsoft
UC responds to EAC recommendations

'Crack' research team develops simple test for early detection of failing concrete

Researchers at the Laboratory have developed a simple, environmentally friendly test to detect concrete flaws and are one step closer to cracking a 50-year-old problem of how to stop a significant cause of concrete fractures.

The test identifies one of the most common causes of concrete degradation, even before cracks and other signs of failure become visible. It gives better results than currently used tests and does not involve hazardous materials.

George Guthrie and Bill Carey of Geology and Geochemistry (EES-1) are using their expertise in mineralogy to understand how concrete ages. Guthrie and Carey are studying chemical reactions that occur within concrete and cause the building material -- of which an estimated 260 million cubic yards were used in the United States last year -- to weather and decay.

Of particular interest to Guthrie and Carey is the so-called alkali-silica reaction. The reaction is responsible for premature degradation of concrete. Its effects can easily be seen on sidewalks as the spider-web network of cracks celebrated in childhood rhymes as things that might break a mother's back if stepped on.

Concrete is a mixture of cement and aggregate, typically rock and sand. The alkali-silica reaction can occur when cement is mixed with aggregate rich in certain types of silica materials. The silica reacts with alkalis in cement and forms a gel inside the concrete. The gel expands dramatically in the presence of moisture and creates a network of microscopic cracks. Freezing and thawing make the cracks worsen over time, and eventually the concrete becomes structurally unsound.

"People have been studying the alkali-silica reaction for about 50 years," said Carey, "but there are still a lot of unsolved mysteries. This work is giving us additional insight into ASR."

The test that Guthrie and Carey have developed not only shows when the reaction is occurring, but has given them insight into how it occurs.

Many areas in the United States -- including New Mexico with its abundance of volcanic rock -- have aggregates that promote alkali-silica reaction in concrete. Because so many highways and highway bridges are constructed with concrete, the alkali-silica reaction is of great concern to transportation officials.

Guthrie and Carey are working with personnel in the New Mexico State Highway and Transportation Department to identify structures that may fall prey to alkali-silica reaction -- long before the cracks formed by expanding gel are apparent.

"In some ways, a diagnostic test that allows you to determine whether ASR is occurring in concrete before there are any symptoms is a lot like catching a disease in the very early stages -- the chances of successful treatment are much better," said Guthrie. "Right now there are no proven methods for reversing ASR, but Bill [Carey] and I are learning a great deal and we hope to come up with a cure."

To aid in early detection of alkali-silica reaction, Guthrie and Carey have developed a simple, environmentally benign test that will identify ASR in concrete: a set of chemicals that can be poured on concrete core samples in the field. If the degrading gel is there, the chemicals stick to it and color it. Results can be obtained in minutes.

Right now, one of the more common tests to detect ASR -- and the primary test recommended to state highway departments by the Federal Highway Administration -- involves the use of uranyl acetate. Concrete core samples treated with the radioactive uranium compound must be viewed under a black light in total darkness; areas where gel may have formed fluoresce under the light.

"We believe our test is a much better diagnostic than the uranyl acetate test and is much easier to use in the field," said Guthrie. "Our test is environmentally friendly, doesn't require any special viewing apparatus and is much cheaper, especially in terms of costs associated with disposal of uranium-bearing materials. Not only that, but the uranyl acetate test can lead to false positives."

As a consequence of their research, Guthrie and Carey have identified two distinct types of gels that form during the alkali-silica reaction and have developed their set of chemicals to indicate the presence of the second gel type. The pair also believe there is a third type of gel and are developing a color test to detect its presence as well.

"These tests are chemically specific and we have greatly reduced the chance of false positives," Carey said.

To test the effectiveness of the chemicals, Guthrie and Carey squared off against four concrete core samples taken from a major urban street in Albuquerque, N.M. Other concrete testing labs looked at the samples as well. Guthrie and Carey were able to successfully determine which samples were inundated with ASR gels. The test also was able to find tiny amounts of ASR that weren't readily apparent.

The new test has the potential to save millions of dollars each year. With early detection of ASR, contractors can identify whether concrete is going to undergo quick degradation. If so, they can use a different source of cement or aggregate. In addition, the test may allow concrete-industry personnel to identify whether an aggregate quarry is going to produce, or is producing, material that leads to ASR.

"But more important," said Guthrie, "we believe that with a greater understanding of these gels as a result of our research, we can now possibly determine exactly why these gels are forming and how to stop them. If you could stop these destructive gels from forming, then we have the potential to save lots and lots of money for the construction industry. That's why this problem is important. Not to mention all the mothers' backs we'll save."

Guthrie and Carey have applied for a patent for the indicator chemicals.

Funding for the project comes from the Lab's Laboratory-Directed Research and Development program. The LDRD program uses about 6 percent of the Laboratory's total budget to support outstanding science and engineering efforts. The program in past years has accounted for nearly 40 percent of the Laboratory's patents and nearly 60 percent of its R&D 100 Awards, and helps Los Alamos retain its intellectual vitality.

In addition, the Laboratory has been working with the New Mexico Alliance for Transportation Research to develop a broader effort in improving the durability of concrete.

--James E. Rickman

PHOTO: Bill Carey, left, and George Guthrie of Geology and Geochemistry (EES-1) treat a concret core sample with a environmentally friendly material that will detect the presence alkali-silica reaction -- a chemical reaction that can destroy the structural integrity of concrete. The test material stains the concrete and shows up yellow in the presence of ASR. Unlike other testing techniques (uranyl acetate, a radioactive material, is now used to detect ASR in concrete), the Guthrie and Carey's test reduces chances of false positives, is easily used and disposed of in the field, is non-toxic and doesn't require any special viewing apparatus. Photo by James E. Rickman

Peña confirmation vote delayed

The Senate Energy Committee announced last Wednesday that it would delay its vote on Department of Energy Secretary designate Federico Peña. It appears the committee has concerns over some of Peña's previous contractor management while at the Department of Transportation and also is signaling its continued displeasure with the administration's inability to make decisions on the disposal of nuclear waste, including specifically addressing the provisions of a new bill introduced by committee chair Frank Murkowski (R-Alaska). This bill would require DOE to begin storing nuclear waste at the Nevada Test Site while a permanent repository is being completed at Yucca Mountain. Source: Feb. 14 Congressional Report

Tri-Lab Day at the Legislature

The Laboratory, Sandia National Laboratories and Phillips Laboratory are co-sponsoring Tri-Lab Day at the Legislature today to showcase lab programs and projects and how they benefit New Mexico.

Laboratory Director Sig Hecker will join his counterparts at Sandia and Phillips labs in giving short talks about the Labs, said Rick Ulibarri of the Government Relations (GRO) Office.

The state Capitol Building is at the intersection of Paseo de Peralta and Old Santa Fe Trail in downtown Santa Fe.

The daylong event begins with a breakfast from 7 to 9 a.m. in the Tesuque Room of the Inn at Loretto just north of the state Capitol. Hecker, Sandia director C. Paul Robinson and Phillips Laboratory director Col. Michael Heil will speak about their lab programs here.

Activities then move to the rotunda of the state Capitol where Lab employees from GRO; Community Involvement and Outreach (CIO); the Industrial Partnership (IPO) Office; Computing, Information and Communications (CIC) Division; and Science Education (STB/SE) are manning an exhibit in the rotunda of the state Capitol Building. The display will include exhibits and other information about the Lab focusing on Lab community and educational outreach and economic development, said Ulibarri. The display will be up until 5 p.m.

The three labs are sponsoring Tri-Lab Day at the Legislature Ulibarri said, to tell state government employees, legislators and other visitors to the state Capitol about programs and projects at the Lab. The event also will help the public better understand the economic benefits to the state from Lab operations, he said.

"We've had a couple of formal requests from interim committees at the state Legislature for greater interaction and more information sharing," said Ulibarri.

"Some of them are not aware of the impact the Lab has in terms of economic development or education programs and other specific outreach programs that help state government directly," he said.

Ulibarri said showcasing what the labs have to offer also is important for New Mexico residents. "We hope to reach out and show them what we're doing," said Ulibarri.

Ulibarri noted that in the 1995 fiscal year, the Lab's total estimated economic impact to the state was pegged at $4.1 billion, or 4.8 percent of the state's total economy.

Direct Lab spending was $1.2 billion, with another $2.9 billion of estimated indirect economic benefits when the economic impact multiplier is factored in, he said.

And of the $4.1 billion, $3.4 billion of that was in Santa Fe, Los Alamos and Rio Arriba counties. Ulibarri said 30 percent of the tri-area economy was dependent on the Lab.

--Steve Sandoval

Lab signs agreement with Microsoft

The Laboratory recently signed an agreement with software company giant Microsoft that allows employees to volume purchase business-related Microsoft products at discounts of 10 to 30 percent. The program, called Microsoft Select, lasts though Dec. 31, 1998.

The agreement is coordinated by the Remote Electronic Desktop Integration Project run by Desktop (CIC-2). REDI is a two-year project that was created last October to address several related computing issues, such as securing software and hardware bulk procurement agreements with local vendors, keeping up with new hardware and software products and upgrades constantly arriving in the marketplace, and providing immediate troubleshooting assistance.

Initially, the program will offer the Windows '95 and NT operating systems and the following Microsoft applications for Windows and Macintosh users: Office Pro, Office Standard, Excel, PowerPoint and Word. Additional software will be added to the list during the program's run. Frank Bobrowicz of CIC-2 said starting soon, the software can be downloaded online through the Electronic Distribution System, obtained physically through Lab vendor CJ Enterprises Inc., or both, depending on the software package involved. In addition, the Research Library (CIC-14) will have CD versions available for loan. The software costs less if obtained online, he noted.

One major feature of Microsoft Select is that for a one-time fee, employees can purchase a maintenance agreement with the software, entitling them to free upgrades and migrations throughout the run of the program, Bobrowicz said.

The fee for these maintenance agreements varies with the software package, ranging from about $250 for Office Pro to about $91 for Word. The fee is prorated based on when you purchased the software and agreement. However, the deadline by which employees can get the maintenance agreement for software they already own is June 30. After that, maintenance agreements only will be available for products purchase under the program, Bobrowicz pointed out.

"This program should save the Lab millions of dollars in costs," said Bobrowicz, adding that if at the end of the program's run Microsoft Select is that successful, the Lab will attempt to renew its agreement with Microsoft.

A fact sheet with frequently asked questions and answers regarding Microsoft Select is available. Employees also should periodically look under "What's New" on the Laboratory's home page for updates on new selections under Microsoft Select. For more information, call Bobrowicz at 5-5531.

--Ternel Martinez

UC responds to EAC recommendations

The University of California's Benefits Office has responded to the Employee Advisory Council's recommendations for health care for Laboratory employees in 1998.

The responses can be found on the Employee Advisory Council home page on the World Wide Web. Go to "Information by Subject" on the Lab's home page then click on Employee Advisory Council. The recommendations and responses are under EAC's "meeting minutes."

The EAC last month submitted its recommendations on employee health care to UC's Benefits Office, said EAC chairperson Tonya Suazo. Among other recommendations, the employee group suggested that the university consider a two-tier approach for 1998; that physicians be allowed to openly communicate with employees about health-care options with no "gag rules" prohibiting open discussion; that most of the basic health-care services, such as regular visits for maintaining good health, emergency and urgent care services, children's and women's health care, and health promotion programs, be covered under tier one of the plan much as a Health Maintenance Organization (HMO) plan does; and that a written grievance procedure be available for employees to file a grievance regarding any aspect of the health plan's services, including the quality of health care and the choice of health-care providers.

EAC also recommended that a UC/Lab health-care-review panel be created; a continuous quality improvement program to monitor the quality of the health-care plan be incorporated; the health-plan administrator be prohibitedfrom offering financial incentives to health-care providers that result in reducing necessary treatments; and that the administrator provide information on how much the health plan is being used and its financial condition.

Suazo said EAC has been able to get UC to understand the importance of employee involvement in the health care issue. "Now we are challenged with working the details of that involvement," she said.

She said some EAC members are meeting today with Michele French, UC's director of health and welfare, to further discuss employee involvement in health care.

--Steve Sandoval

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