1、COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-L3b 92 Obb2949 050b275 584 = r + 5-O C. TO C. .) Structural Lightweight Aggregate Concrete Performance Thomas A. Holm Alexander M. Vaysburd Editm SP-136 COPYRIGHT ACI International (American Conc
2、rete Institute)Licensed by Information Handling ServicesAC1 SP-136 92 = 0662949 0506276 410 DISCUSSION of individual papers in this symposium may be submitted in accordance with general requirements of the AC1 Publication Policy to ACI headquarters at the address given below. Closing date for submis
3、sion of discussion is July 1, 1993. All discussion approved by the Technicai Activities Committee along with closing remarks by the authors will be published in the January/February 1994 issue of either AC1 Structural Journal or Joumai depending on the subject emphasis of the individual paper. The I
4、nstitute is not responsible for the statements or opinions expressed in its publications. Institute publications are not able to, nor intended to, supplant individual training, responsibility, or judgment of the user, or the supplier, of the information presented. The papers in this volume have been
5、 reviewed under Institute publication procedures by individuais expert in the subject areas of the papers. Copyright 1992 AMERICAN CONCRETE INSTiTUTE P.O. Box 19150, Redford Station Detroit, Michigan 48219 Ail rights reserved including rights of reproduction and use in any form or by any means, incl
6、uding the making of copies by any photo process, or by any electronic or mechanical device, printed or written or oral, or recording for sound or visual reproduction or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors. PM
7、ed in the United States of America Editoriai production Victoria Wiecmrek J Library of Congress catalog card number 92-75275 COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-LIb 92 Ob62949 0506277 357 PREFACE This volume is a compilation of pap
8、ers addressing the “Performance of Structural Lightweight Concrete“ presented at the November 14, 1991 technical session of the American Concrete Institute fall convention in Dallas, Texas. Planning for this symposium, sponsored by AC1 Committee 213, “Structural Lightweight Aggregate,“ was in respon
9、se to construction industry and engineering community interest in using structural lightweight concrete in severe environment applications. The immediate need for disseminating state-of-the-art information motivated the development of this two session symposium. The speakers addressed topics ranging
10、 from fundamental laboratory studies to case histories of concrete performance. The papers include ap- plication of lightweight concrete for bridges, arctic structures, buildings and parking structures, aspects of structural design, production and durability of lightweight concrete structures. We th
11、ank the authors for sharing their knowledge, and Messrs. John P. Ries and Dr. Theodore W. Bremiier for serving as session Co-chairmen. A special note of appreciation is directed towards the many session paper reviewers and to the support and constructive suggestions offered by the 213 committee memb
12、ers and their chairman, David Akers. Thomas A. Holm Alexander M. Vaysburd Session Chairmen I iii COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-136 92 D Obb2949 0506278 293 D AC1 Coiiimittee 213 LIGHTWEIGHT AGGREGATES AND LIGHTWEIGHT AGGREGAT
13、E CONCRETE David J. Akers Chairman Olga L. Aionzo Stanley G. Barton Paul M. Bercheny Theodore W. Bremner Philip M. Carkner Russell A. Cook Gary D. Courts David A. Crocker Calvin L. Dodl Frank G. Erskine John H. Faber Per Fidjestol Samuel B. Helms Thomas A. Holm William W.J. Hotaling David D. Imrie D
14、onald W. Lewis Mark D. Luther W. Calvin McCall Avi A. Mor Vladimir Novokshcheiiov iv John Pauley H. Kent Preston John P. Ries George M. Robinson Hariy C. Robinson Peter G. Snow Parviz Soroushian Alfred E. Spamer Jeffrey F. Speck Paul R. Stodola William X. Sypher Kenneth L. Teel Robert E. Tobin Samue
15、l S. Tyson Rudolph C. Valore, Jr. Alexander Vaysburd Linda F. Whitehead William J. Wilhelm John C. Wycoff Min-Hong Zhang COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-13b 92 Obb2949 050b279 L2T CONTENTS I . Preface . 111 HIGH STRENGTH LIGHTW
16、EIGHT AGGREGATE CONCRETE FOR ARCTIC APPLICATIONS-PART 1 byG.C.Hoff . 1 HIGH STRENGTH LIGHTWEIGHT AGGREGATE CONCRETE byG.C.Hoff 67 FOR ARCTIC APPLICATIONS-PART 2 HIGH STRENGTH LIGHTWEIGHT AGGREGATE CONCRETE by G.C. Hoff . 175 FOR ARCTIC APPLICATIONS-PART 3 THE ADVANTAGES OF USING LIGHTWEIGHT CONCRETE
17、 IN A MEDIUM RISE BUILDING AND by R. Trumble and L. Santigo . 247 ADJOINING POST-TENSIONED PARKING GARAGE LIGHTWEIGHT CONCRETE BRIDGES FOR CALIFORNIA HIGHWAY SYSTEM by J.E. Roberts 255 LIGHTWEIGHT MICROSILICA (SILICA FUME) CONCRETE IN THE USA by M.D. Luther . 273 DURABILITY OF LIGHTWEIGHT CONCRETE A
18、ND ITS CONNECTIONS WITH THE COMPOSITION OF CONCRETE, by A.M. Vaysburd 295 HIGH DUCTILITY, HIGH STRENGTH LIGHTWEIGHT AGGREGATE CONCRETE by D.E. Berner 319 I DESIGN AND CONSTRUCTION METHODS I V COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-13b
19、 92 m Ob62949 050b280 941 m INFLUENCE OF COMPRESSIVE STRESS ON THE PERMEABILITY OF CONCRETE by T.W. Bremner, T.A. Holm, and J.M. McInerney . 345 FLEXURAL BEHAVIOR INCLUDING DUCTILITY OF HIGH STRENGTH LIGHTWEIGHT CONCRETE MEMBERS UNDER REVERSED CYCLIC LOADING by S.K. Ghosh, D.P. Narielwala, S.W. Shin
20、, and J. Moreno 357 PORE STRUCTURE AND CARBONATION OF LIGHTWEIGHT CONCRETE AFTER 10 YEARS EXPOSURE by R.N. Swamy and E.D. Jiang 377 FATIGUE STRENGTH AND ENDURANCE LIMIT OF LIGHTWEIGHT CONCRETE by V. Ramakrishnan, T.W. Bremiier, and V.M. Malhotra . 397 SI (metric) TABLES 421 INDEX . 423 COPYRIGHT ACI
21、 International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-136 92 W Obb2949 050b28L 888 W SP 136-1 High Strength Lightweight Aggregate Concrete for Arctic Applications-Part 1 by G.C. Hoff SmoDsis: This paper is Part 1 of a three part paper which presents the results
22、of a Joint Industry Project to develop high strength lightweight aggregate concretes for use in the Arctic. Described in Part 1 are the lightweight aggregate selection tests, high strength mixture development with the selected aggregates, batching procedures, unhardened properties of the 110 batches
23、 made during the program, and the temperature development of the mixtures in large sections of concrete. Both crushed and pelletized lightweight aggregates were used with supplementary cementing materials and high-range water reducers to produce concretes with compressive strengths from 8,000 psi (5
24、5 MPa) to 11,000 psi (76 MPa) . Also evaluated was the influence of pumping on the aggregate moisture content, slump, unit weight, air content, and concrete strength. The effects of the air void system in the hardened pumped concrete with respect to freezing and thawing durability and the drying beh
25、avior of a large section of concrete were also evaluated. Kevwords: Air entrainment; arctic concrete; blast furnace slag; cold weather construction; compressive strength; diying; fly ash; freeze thaw durability; harbor structures; high strength concretes; lightweight mreeates; marine atmospheres; of
26、fshore structures; pumped concrete; silica fume; slump; temperature; tensile strength; unit weight 1 COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling Services2 Hoff I INTRODUCTION George C. Hoff, FACI, received his Doctorate in Civil Engineering from Texas A&
27、M University. He has worked in the field of concrete and construction materials for 30 years and joined the Engineering Department of Mobil Research and Development Corporation 1982. He is the current Chairman of the American Concrete Institute Committee 357, Offshore and Marine Concrete Structures.
28、 The study of the use of high-strength lightweight aggregate concrete for Arctic applications was a 3-112 year, 3 Phase effort conducted as a joint-industry project involving 11 companies (See ACKNOWLEDGMENTS). The complete results of the study can be found in (1, 2, and 3). A summary of results are
29、 presented in 3 parts in the Proceedings of this Symposium. Part 1, described herein, presents the study rationale, materials selection, mixture development, and unhard- ened concrete properties including temperature develop- ment and pumping considerations. Part 2 (4) presents the test results from
30、 the mechanical testing of the hardened concretes described in Part 1. These include strength and modulus, creep and shrinkage, permeability and absorption, thermal characteristics, ice bond development strength, and durability observations. Part 3 (5) presents the results from more complex structur
31、al parameter determinations to include stress versus strain behavior, multiaxial stress behavior, beam shear strength, bearing strength, shear-friction capacity, and reinforcement development length. The study also evaluated the effectiveness of coatings in reducing both the friction coefficient at
32、the ice/structure interface of an offshore Arctic structure. As the coating study was not directly evaluating the high-strength lightweight aggregate concrete but only the coatings, it is not included in this 3 Part summary. The complete results of the coating study can be found in (3). This Part of
33、 the 3 Part summary presents the target concrete properties used throughout the program, the selection process for the lightweight aggregates, mixture development to meet the target properties, and the unhardened properties of the 110 batches of the concrete made over the duration of the program. Th
34、e hardened properties from those batches are described in Parts 2 and 3 (4,5) of this paper. Once the final mixtures were selected for the program, the heat COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-136 92 0662949 0506283 650 Lightweight
35、 Concrete 3 development that each would produce in large sections of concrete was evaluated along with the effects of that heat on the compressive strength of the in-situ concrete. One mixture was selected for use in a field pumping tests using actual field pumping equipment. This test was used to e
36、valuate the effects of pumping on the moisture content of the lightweight aggregate, the effects on slump, unit weight, and air content in the unhardened concrete, and the effects on both the compressive strength and air void system in the pumped concrete after it had hardened. A large section of co
37、ncrete was also produced and evaluated with respect to rates of drying of the concrete. CONSIDERATIONS IN THE USE OF CONCRETE IN OFFSHORE ARCTIC S!l!RUCTRJZS Concrete has been proven as a durable, efficient, cost- effective construction material for offshore and marine structures in temperate and su
38、b-arctic locations. It has also been seriously considered for developments in the Arctic because of its well-established record of providing adequate structural performance at extremely low temperatures. Two offshore exploration structures (6 and 7) for Arctic use have been built with light- weight
39、aggregate concrete and successfully used in the arctic environment. The exploration and production structures being considered for Arctic applications are usually bottomed-founded gravity base structures which function as a floating vessel until they are permanent- ly installed. For more information
40、 on these types of structures, the reader is referred to a detailed report (8) prepared by AC1 Committee 357, Offshore and Marine Concretes. Many unique considerations enter into the design, construction, installation, .and operation of a concrete structure for use in the Arctic that normally would
41、not influence the structure if it were used in a more moderate climate. The first of these is that it cannot be economically built close to where it will be used because of the extremely low temperatures that exist in the Region for most of the year. For structures that might be used in the United S
42、tates and Canadian Arctic or the eastern Arctic of the Soviet Union, they would most likely be built in the Pacific Basin south of the Aleutian Islands and towed to their final location. Anticipated construction locations for those structures have access to lightweight aggregate sources. The second
43、consideration is that the structure must have as much as possible of its operating equipment and COPYRIGHT ACI International (American Concrete Institute)Licensed by Information Handling ServicesAC1 SP-13b 92 = 0662949 0506284 597 4 Hoff consumables on it when it is towed to the Arctic. The ice-free
44、 season, when crane barges and supply boats can access the structure at its installed location, is very limited. If possible, the structure should have all of its equipment and at least nine months consumablec on it when it is towed. The total weight of these items can easily be between 70,000 to 12
45、0,000 tons (64,000 to 109 , O00 tonnes) depending on the operational requirements of the structure. The third consideration is the draft at which the fully loaded structure will be towed and installed. Draft limitations exist in the Bering Strait through which the structure must pass on its way to t
46、he Arctic. The water depth where the structure will be installed is extremely critical as the structure must be able to float over the final location before it is ballasted down to the sea floor. The large equipment and consumable weight , together with the weight of the structure, displaces very la
47、rge amounts of water. To accommodate this displacement, the structure must be quite large in base area in order to have an acceptable draft. By using lightweight aggregate concrete in the structure rather than normal weight concrete, for a desired draft, the weight of the structure can be reduced be
48、tween 20 to 30 percent thus allowing more equipment and consumables weight to be carried for a given size of structure, or the size of the structure can be reduced for a given weight. The focus of this research program was to examine many of the aspects of arctic environment that might adversely aff
49、ect the selection of the lightweight aggregate concrete for these structures. Not all lightweight aggregates are suitable for use in that environment so a proper selection process is necessary. The lightweight aggregate concrete will be subjected to unusually severe freezing and thawing exposures, continual saturation in sea water with the potential for chloride ion infiltration, impact and abrasion from floating ice, and the formation of sea ice on surface of the structure. To provide satisfactory performance against most of these demands, the lightweight aggregate concrete needs to ha
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