1、Investigating Concrete: Selected Works of Bryant and Katharine Mather Together, Katharine and Bryant Mather have contriuted over I O0 years of scientific work for concrete research and development activity for the US. Army Corps of Engineers and have participated in many technical organizations, suc
2、h as the American Concrete Institute ACI), the American Society for Testing and Materials ASTM), the Transportation Research Board TRB), and others. Ed it0 rs: Celik Ozyildirim Shuaib Ahmad American Concrete Institute“ SP-223 Advancing concrete knowteje AC1 Special Publication INVESTIGATING CONCRETE
3、 Selected Works of Bryant and Katharine Mather Editors: Celik Ozyildirim Shuaib Ahmad American Concrete Institute“ Aduanring concrete knowle cementitious materials; aggregates; durability of concrete; petrographic examination of aggregates and concrete; specifications for use of concrete in transpor
4、tation structures; and research and emerging technologies. This publication also includes an appendix with a bibliography of selected works of Bryant and Katharine Mather. Bryant helped in developing a comprehensive list of their publications. Per Bryants request, Katharine was added to the title an
5、d several of her papers were added to this publication. The total number of publications was in excess of 800. The list was reduced to 400 by identiymg papers dealing with concrete materials only. Bryant, Celik Ozyddirim, and Shuaib Ahmad met at AC1 Headquarters to further reduce the list to a more
6、manageable 164 publications. This reduced list of 164 citations is included in the appendix of this publication. Together, Katharine and Bryant Mather have contributed over 1 O0 years of scientific work for concrete research and development activity for the U.S. Army Corps of Engineers and have part
7、icipated in many technical organizations, such as the American Society for Testing and Materials (ASTM), Transportation Research Board (TRB), American Concrete Institute (ACI), and others. Their work has significantly contributed to the advancement and better understanding of concrete. On September
8、25,2001, the U.S. Army Engineer Research and Development Center renamed its structures laboratory building the Katharine and Bryant Mather Building. Bryant started his career in August 1941, when he accepted a job as a junior geologist with the Central Concrete Laboratory at the U.S. Military Academ
9、y at West Point, N.Y. Not long thereafter, Bryant began to examine aggregate to associate rock types with “soundness.” Katharine started her career at the same laboratory in April 1942. She also had assignments performing microscopic petrography. She, like Bryant, had more semester hours of petrogra
10、phy during her graduate work at Johns Hopkins University than any other geological specialty. Both Bryant and Katharine were assigned to work on the preparation of the Handbookjv Concrete and Cement-a compilation of test methods, specifications, terminology, and standards in concrete technology deve
11、loped or modified and adopted for use by the Corps of Engineers. Throughout their careers, Bryant and Katharine made important contributions to concrete petrography. They Co-authored a paper on petrographic methods for concrete aggregates, which was the basis for ASTM C 295, adopted in 1954. As of 2
12、002, ASTM C 295 still cites this paper as its first reference. Katharine Mather compiled the contributions made by the use of light microscopy to concrete research, which was published as part of a symposium, sponsored by the ASTM committee on microscopy. The paper was selected by ASTM Committee C 0
13、9, Concrete and Concrete Aggregates, to receive the Sanford E. Thompson Award for 1961. 5 Katharine later collaborated with Tom Kennedy to produce petrographic data on concrete exposed to freezing and thawing at Treat Island, Maine. She compared the data with specimens of the same batches subjected
14、to freezing and thawing in the laboratory. This paper was published in the ACI Journaland was selected for the Wason Medal in 1955. When the Mathers joined the Corps of Engineers Concrete Laboratory in 1941, the principal research effort at the laboratory was the Cement Durability Program, in which
15、durability primarily referred to resistance to freezing and thawing. Bryant further discussed the subject of freezing and thawing in his paper “How to Make Concrete That Will be Immune to the Effects of Freezing and Thawing,” which was published in AC1 SP- 122, Paul Klieger Symposium on Pe fomance o
16、f Concrete. Over the last 50 years, the contributions of Bryant and Katharine have been recognized in many ways by various organizations, including ACI, ASTM, and TRB. The Proceedings of the Katharine and B7yant Matber International Conference Co-sponsored by the American Concrete Institute and publ
17、ished as AC1 SP-100, Concrete Durabikp: Katbarine and Bvant Matber International Conference, consists of two volumes totaling 2,179 pages. One of Bryants last contributions to the concrete industry was his tireless work on the revision of AC1 SP-1, Concrete Primer, which was published by the America
18、n Concrete Institute in 2002. The editors hope that this commemorative publication to honor Katharine and Bryant Mather is well received and provides a good comprehensive overview of their distinguished contribution to the concrete industry. 6 TABLE OF CONTENTS Part I . Potential of Concrete . 7 Rea
19、heng the Potential of Concrete as a Constmction Materia l. Part II . Cementitious Materials 21 Efectiveness ofMineral Admxtures in Preventing Excessive Expansion $Concrete Due to Alkali- Agregate Reaction . 23 Concrete Agregate: Shqe. Su face. Textun. and Coatings 57 Reflections on Concrete Durabihg
20、 and on International Conferences on Concrete Durabihg . 81 How to Make Concrete that Wll Be Immune to the Efects ofFreeeng and Tbawng 89 Cystal Growth in Entrained-Air Voids 105 How to Make Concrete That Will Not Sufer Deleterious Alkali-Slca Reaction . 127 Suyate Soundness, Suyate Attack, and Expa
21、nsive Cement in Concrete 135 Suyate Attack on Hydrauhc-Cement Concrete . 143 Method of Petrogrqhc Examination $Aggregates for Concrete . 155 Applications of Lght Mmscqy in Concrete Research 185 Part VI - Specifications for use of Concrete in Transportation Structures 207 Part III . Aggregates . 55 P
22、art IV - Durability of Concrete . 79 Resistance to Freezing and Thawing Resistance to Alkali-Aggregate and Alkali-Silica Reactions Cracking of Concrete in the Tuscaloosa Lock . 107 Resistance to Sulfate Attack Part V - Petrographic Examination of Aggregates and Concrete . 153 Concrete in Tranqortati
23、on: Desired Pe fomance and Spea3cations . 207 Part VI1 - Research and Emerging Technologies 217 Research on Concrete 221 Robert E . Le and Concrete . 239 Se has infinite variability, but can be made very uniform; and can be made to last as long as you want it to. Therefore, what is needed to more fl
24、ly realize its potential as a construction material is to understand what we want it to do, learn how to make it so it will do so, use available methods to restrict undesired variability, consider the ethical and environmental aspects of its use, and help the people who are making it to do it better
25、. Keywords Concrete; Durability; Environment; Ethics; Service life; Specification overkill; Statistical methods; Uniformity; Variability Dr. Bryant Mather is Director of the Structures Laboratory, U.S. Army Engineer Waterways Experiment Station, 3909 Halls Ferry Road, Vicksburg, MS 39180-6199, USA.
26、He is a Past-President of AC1 and ASTM and has served on numerous AC1 and ASTM committees. He is a prolific author and editor and has received numerous awards and honors from ACI, ASTM, and other institutions. INTRODUCTION When the question of ?realizing the potential of concrete as a construction m
27、aterial? was suggested to me as the subject of these remarks, my first reaction was, what is there that has been built using construction materials that hasn?t been built using concrete? What unrealized potential does concrete have as a construction material? Or perhaps one first needs to define ?co
28、nstruction? - and then ?construction material.?, Stein (1993) includes in ?Construction Categories? a list of building types and uses ranging from ?Animal Clinic,? ?Bank,? ?Dog Iennel,? ?Factory,? ?Garage,? ?Jail,? ?Museum,? ?Roundhouse,? ?Stable,? and ccTheater,y? to ?Warehouse.? I believe that exa
29、mples of all of these have been built using concrete. I therefore concluded that perhaps the opportunity presented by this title is not so much to talk about how to construct some category of construction that has never before been produced using concrete, but rather describing how to do concrete wo
30、rk of the kind that the human race has been engaged in to some degree or other for the past eight dennia (Malinowski and Friefelt 1993) but doing it better so as to serve better, at lower social cost. We need, inter alia, to learn how to better realize the potential of concrete as a construction mat
31、erial by producing it with the use of less energy and smaller emissions of greenhouse gases. 1 U.S. Army Engineer Waterways Experiment Station, United States of America 11 Even as was the case with these remarks, in 1987 the organizers of the First International Conference on Concrete Durability inv
32、ited Katharine Mather and me to speak at the opening session. On that occasion, the version that was published had the title “Reflections on Concrete Durability and on Intemational Conferences on Concrete Durability” (Mather and Mather 1987). In it, we reiterated a number of well-known relevant fact
33、s about concrete. I restate them in slightly revised form as an introduction. Concrete is international and as we have air to breathe. water to drink. earth to mow dants in: it provides for all that which the 1976 National Readv Mixed Concrete Associations U.S. Bicentennial bumDer sticker said: - “C
34、oncrete - the Foundation of America.” and that can now be exDanded to Concrete - the Foundation of Civilization.” Concrete is made locally-The mixing water, with negligible exceptions (perhaps when concrete is made on the moon); the aggregates usually; the cement often, are or are made from one or m
35、ore locally available natural raw materials, after various degrees of processing. Concrete has infinite variability-The varieties of concrete that are intentionally produced are more numerous than the known varieties of natural sedimentary rocks. Concretes have been - and will be - required to be pr
36、oduced having densities from as low as 160 kg/m3 (10 lb mass/ft3) to as high as 4800 kg/m3 (300 lb mass/ft3); that have unconfined compressive strengths from as low as 0.35 MPa (50 psi) to as high as 275 MPa (40,000 psi); that are of any color white, black, pink, turquoise, chartreuse, or as one Cor
37、ps of Engineers officer demanded, “sand tan;” we await the demand for “olive drab.” Concrete can be made to be very uniform-AC1 Committee 214 was organized in 1946. It told concrete makers and users how to use strength tests to measure uniformity of concrete as produced and still does. In 1979, ASTM
38、 Standard Method C 917 for Evaluation of Cement Strength Uniformity was adopted. For many years ASTM Specification C 33 has put rather restrictive limits on uniformity of grading of fine aggregate in terms of fineness modulus. There are uniformity requirements on pozzolans given in ASTM Specificatio
39、n C 618. Concrete can be made to last as lono as you want it to-Even as some relatively fragile sedimentary rocks exist that have survived some hundreds of millions of years, so there are concretes that, if they remain in relatively mild environments, could last forever or at least as close to forev
40、er as we can measure. The duration of the life of a concrete with its relevant properties not sufficiently degraded so as to impair or jeopardize its ability to serve its intended purpose, is not usually a function of the absolute level of any universally relevant property of the concrete such as sl
41、ump, density, strength, modulus of elasticity, or color but is almost always a function of the interaction of some property or properties, the required levels of which depend on the severity of the environment to which the concrete will be exposed in service. One need not worry much about resistance
42、 to freezing and thawing in the tropics, except in facilities using refrigeration; or at the poles, except in facilities using intermittent heating. One need not worry about acid attack, abrasion attack, sulfate attack, attack by boring or burrowing molluscs, or any of the myriad hazards described b
43、y IUeinlogel(1950), Biczok (1976), or others except where they exist and impact the concrete of interest. And where these potentially destructive influences can be and are brought to bear on the concrete, if their action and its intensity and duration are property anticipated, the concrete can be re
44、ndered adequately resistant so as to ment the designation durable, even when as demanded of us by authorities dealing with the storage of nuclear waste, means not significantly degraded for many centuries or in some cases hundreds of centuries. 12 With these considerations in mind, what is there to
45、say about the unrealized potential of concrete as a construction material? In my view, several things: First, what do we need to do that we are not doing that, if we did it, would greatly reduce the number of cases of premature degradation of concrete in service. Too much concrete that should last a
46、t least 50 or 100 years with minimal damage is showing serious damage in a tenth or less of that time. And, next, what do we need to do that we are not doing that if we did it, would greatly reduce the cost of concrete by not paying extra to provide resistance to aggressive influences that have negl
47、igible likehhood of being encountered by the concrete in its intended service life. We now, often, pay a lot to provide frost-resistant concrete for use in regions where natural freezing has not taken place for millions of years. If we only ordered what we need and can benefit from, wed have fewer t
48、hings to look out for through quality control and quality assurance, and that, too, would contribute to lowering the cost. One important matter, therefore, is to know how properly to assess the nature and severity of the environment of service; to get a reasonable estimate of intended service life;
49、to get a reasonable assessment of how much degradation is tolerable structurally and, when relevant, aesthetically. One must then, from these and known relationships of environmental influences and concrete composition and constitution, have and use procedures and criteria by which to select materials, proportions, and construction practices that will, with reasonable probability of success and compliance with the owners budget for the work, give concrete that will not prematurely deteriorate. Most of the knowledge to do this exists, some in relatively quite refined sta
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