1、 Concrete: Material Science to Application A Tribute to Surendra P. Shah Editors P. Balaguru A. Naaman W. Weiss international SP-206 DISCUSSION of individual papers in this symposium may be submitted in accordance with general requirements of the AC1 Publication Policy to AC1 headquarters at the add
2、ress given below. Closing date for submission of discussion is October 2002. All discussion approved by the Technical Activities Committee along with closing remarks by the authors will be published in the JanuaryFebruary 2003 issue of either AC1 Structural Journal or AC1 Materials Journal depending
3、 on the subject emphasis of the individual paper. The Institute 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 inf
4、ormation presented. The papers in this volume have been reviewed under Institute publication procedures by individuals expert in the subject areas of the papers. Copyright O 2002 AMERICAN CONCRETE INSTITUTE P.O. Box 9094 Farmington Hills, Michigan 48333-9094 All rights reserved, including rights of
5、reproduction and use in any form or by any means, including 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
6、writing is obtained from the copyright proprietors. Printed in the United States of America Editorial production: Bonnie L. Gold Library of Congress catalog card number: 2002103339 ISBN: 0-8703 1-075-5 Surendra (Suru) Poonamchand Shah, the son of a Gujarati businessman, grew UP in Mumbai (Bombay), I
7、ndia and attended Modem School and Elphinstone College where he became President of the Literary Society. While in Engineering College, he played the leading role in a drama that traveled to New Delhi and was performed in front of the then Prime Minister, Jawaharlal Nehru. For Suru, this tour of Ind
8、ia was a memorable introduction to the delights of travel, an aspect of his academic career that he genuinely enjoys. Among Surus other passions are exploring cuisine and wines in restaurants worldwide, investigating archaeological and architectural wonders of the world, analyzing theatre, opera, an
9、d film productions, and entertaining visitors to Chicago and Evanston, as well as working with students, post-docs, and colleagues. After earning a B.E. at Sardar Vallabhbhai Vidyaputh Gujarat University, SUN came to the United States for graduate study at Lehigh University where he completed a Mast
10、er of Science degree. For two years, he worked as a design engineer for Modjeski and Masters, a bridge design firm in Harrisburg, Pennsylvania, where he met Dorothie Crispell, whom he married before he enrolled in the Ph.D. program in civil engineering at Cornel1 University. There, Professor George
11、Winter, Professor Richard White, and Professor Floyd Slate were his research mentors. In 1965, Suru joined the faculty of the Materials Engineering Department at the University of Illinois in Chicago. In addition to teaching a variety of civil engineering classes, he developed a state-of-the-art res
12、earch laboratory and built a graduate program. He was rapidly promoted to associate, then full, professor. In 1981, he joined the faculty at Northwestern University where he holds the Walter P. Murphy Chair in Civil Engineering. SUN was key in establishing the pioneering National Science Foundation
13、Science and Technology Center for Advanced Cement Based Materials and has served as director since its inception in 1989. The ACBM Center is a multi- disciplinary consortium comprised of five institutions: Northwestem University, University of Illinois at Urbana-Champaign, University of Michigan at
14、Ann Arbor, Purdue University, and the National Institute of Science and Technology. The goal of the center is to improve knowledge of cement and concrete so that stronger, tougher, and more-durable materials are economically produced for infrastructure facilities and other structures. With ACBM Cent
15、er colleagues, post-docs, and graduate students, Suru continues his tireless pursuit of fundamental understanding of cement-based materials and related fiber- reinforced cement composites. Currently, a consortium of world-class industrial partners provide strong support for the ACBM Center and assis
16、t the center in promoting improved teaching of the materials science of concrete. Sums accomplishments are too numerous to list here; suffice it to say that anyone involved in the materials science of concrete, fracture mechanics, high- performance concrete, or fiber-reinforced concrete has encounte
17、red and utilized his contributions. He has Co-authored two textbooks, edited over a dozen books, and published more than 400 papers. Suru has received many major professional and technical awards, including the AC1 Arthur R. Anderson Award, the RILEM Gold Medal, the Swedish Concrete Award, the Alexa
18、nder von Humboldt Award, Engineering Newsletter Award, ASCE-CERF Charles Pankow Award, and ASTM Thompson Award. He has been the principal advisor of almost 100 graduate students and supervised the work of over 60 post-docs and visiting scholars. Contributors to this symposium in his honor include ma
19、ny of his former students. A list of former students and post-docs appear in the Appendix. Suru and Dorothie Shah have two married sons, Byron and Daniel, and a grandson, Kian, bom in 1999. It is with great respect, admiration, and affection that members of the organizing committee of this symposium
20、 dedicate this volume in tribute to their colleague, mentor, and friend, Surendra P. Shah. The Organizing Committee April 2002 P. Balaguru Rutgers University D. Lange University of Illinois at Urbana-Champaign N. Banthia A. Naaman University of British Columbia University of Michigan J. Biemacki W.
21、Weiss Tennessee Technical University Purdue University V. Gopalaratanam University of Missouri TABLE OF CONTENTS . Preface 111 ADVANCES IN FATIGUE AND FRACTURE Failure Mechanism of Reinforced Concrete by T. C. Hsu and M. Y. Mansour Elements Under Cyclic Loading . 1 Fatigue Fracture and Crack Propaga
22、tion in Concrete Subjected to Tensile Biaxial Stresses 25 by K. V. Subramaniam, J. S. Popovics, and S. P. Shah Analysis of Reinforced Concrete Beams Strengthened with by C. G. Papakonstantinou, P. N. Balagum, and M. F. Petrou Composites Subjected to Fatigue Loading . 41 Fatigue Investigation of the
23、Steel-Free Bridge Deck Slabs 61 by A. A. Mufti, A. H. Memon, B. Bakht, and N. Banthia Mechanical Behavior of the Interface Between Substrate by P. Paramasivam, K. C. G. Ong, and W. Xu and Repair Material 7 1 Fatigue Characteristics of Fiber Reinforced Concrete for by V. S. Gopalaratnam and T. Cheria
24、n Pavement Applications . 91 Assessment of Stresses in Reinforcement of by J. Halvonik and M. W. Wang Kishwaukee River Bridge . 109 Some Australian Code Developments in the Design of Concrete Structures 123 by B. V. Rangan CREEP, SHRINKAGE, AND EARLY-AGE CRACKING Holistic Approach to Corrosion of St
25、eel in Concrete . 137 by N. S. Berke, M. C. Hicks, J. J. Malone, and K.-A. Rieder Study of the Behavior of Concrete with Shrinkage Reducing by R. Gettu, J. Roncero, and M. A. Martin Admixtures Subjected to Long-Term Drying . 157 V Influence of Superplasticizer on the Volume Stability of by B. Bisson
26、nette, J. Marchand, C. Martel, and M. Pigeon Hydrating Cement Pastes at an Early Age . 167 Grip-Specimen Interaction in Uniaxial Restrained Test 189 Restrained from Volumetric Changes . 205 by S. A. Altoubat and D. A. Lange Using Acoustic Emission to Monitor Damage Development in Mortars by T. Chari
27、ton and W. J. Weiss Modeling of Restrained Shrinkage Cracking in Concrete Materials 219 by S. A. Mane, T. K. Desai, D. Kingsbury, and B. Mobasher Field Study of the Early-Age Behavior of Jointed by H-L. Chen, T. H. Schell, and J. G. Sweet Premature Transverse Slab Cracking of Jointed Plain Concrete
28、by W. Hansen, D. L. Smiley, Y. Peng, and E. A. Jensen Plain Concrete Pavements 243 Pavement-Environmental and Traffic Effects . 259 Evaluation of Bond-Slip Behavior of Twisted Wire Strand Steel Fibers Embedded in Cement Matrix 271 by C. Sujivorakul and A. E. Naaman Early Age Stress-Hydration Kinetic
29、s and Thermomechanics . 293 by I. Pane and W. Hansen Thermal and Chemical Activation of High Flyash Content Cement Based Materials . 303 by S. Mane and E. Mobasher LAMINATED AND FIBER REINFORCED CEMENT COMPOSITES Ferrocement: International Revival 323 by A. E. Naaman Textile Fabrics for Cement Compo
30、sites . 341 by A. Peled and A. Bentur Thin Plates Prestressed with Textile Reinforcement 355 by H. W. Reinhardt, M. Krger, and C. U. Grosse VI Advances in ECC Research 373 by V. C. Li PVA Polymer Modified Glass Fiber Reinforced by Z. Li, A. C. P. Liu, and C. K. Y. bung Cementitious Composites . 401
31、Fiber Reinforced Cement Based Composites Under Drop Weight by N. Banthia and V. Bindiganavile Impact Loading: Test Equipment can explain the mechanism behind the ?pinching effect?; and can elucidate the failure mechanism that causes the deterioration of reinforced concrete structures under I , I cyc
32、lic loading. Kevwords: cyclic loading; mechanism; pinching; reinforced concrete; shear; strain; steel; stress; softened truss models I 1 2 Hsu and Mansour AC1 Fellow Thomas T. C. Hsu is Moores Professor in the Dept. of Civil and Envir. Engineering at the University of Houston. He was the recipient o
33、f ACIs Anderson Award for research in 1990, and Wason Medal for material research in 1965. He is a member of AC1 committee 215, Fatigue of Concrete; and joint ACI-ASCE committee 343, concrete bridge design; and 445, shear and torsion. M. Y. Mansour is Assistant Professor in the Dept. of Civil Belarb
34、i and Hsu, 1994, 1995; Pang and Hsu, 1995), (3,4,5,6), the fixed-angle softened truss model (FA-STM) (Pang and Hsu, 1996; Hsu and Zhang, 1997, Zhang and Hsu, 1998), (7,8,9), and the softened membrane model (SMM) (Zhu, 2000; Hsu Zhu and Hsu, 2002; Hsu and Zhu, 2002), (10,11,12,13). The SMM is an exte
35、nsion of the FA- STM with two improvements: First, SMM can predict the entire load- deformation history of panel behavior, including the post-peak descending branches, because the HsdZhu ratios (or Poisson effect) are taken into account. Second, the complicated and empirical shear modulus of concret
36、e in FA-STM is replaced by a simple and rational shear modulus in SMM. As a result, the solution algorithm of SMM is considerably simpler and the prediction more accurate than those of FA-STM. In order to predict the behavior of membrane elements under cyclic loading, SMM for monotonic loading was e
37、xtended for application to cyclic loading by adding the constitutive models of materials (concrete and embedded steel bars) in the unloading and reloading regions (Mansour, 2001; Mansour, Lee and Hsu, 2001; Mansour, Hsu and Lee, 2001), (14,15,16). This paper presents a new model, called the “Cyclic
38、Softened Membrane Model (CSMM),” that is capable of predicting the entire cyclic history of load-deformation relationship, including the post-yield hysteretic loops and the pinching effect. Applying the CSMM to predict the behavior of two panels CA3 (a2 = 45) and CE3 (a2 = 90”), this paper discusses
39、 rationally the presence and absence of the pinching effect in the hysteretic loops. The comparison of the behavior of these two panels not only reveals the mechanism inherent in the pinching phenomenon, it also elucidates the failure mechanism of reinforced concrete composites under cyclic loading.
40、 TESTS OF R/C SHEAR PANELS CA3 AND CE3 The two test panels, CA3 and CE3, have a size of 1398 mm x 1398 mm x 178 mm, and the steel bars are placed at angles 1x2 of 45 and 90 degrees, respectively, as shown in Fig. 1, to form orthogonal steel grids. The reinforcing ratios of panels CA3 and CE3 are 1.7
41、% and 1.2%, respectively, in each direction. The material properties for these two panels are summarized in Table 1. The panels were subjected to reversed cyclic stresses in the horizontal and vertical directions using the Universal Panel Tester. When these two principal applied stresses were equal
42、in magnitude and opposite in direction, a state of 4 Hsu and Mansour pure shear stress rd5- was created at the 45direction to the applied principal stresses. The testing facility was equipped with a servo-control system capable of switching fi-om load-control mode to strain-control mode as the yield
43、ing load was approached. In the strain-control mode, the shear strain (i.e. the algebraic sum of the horizontal and vertical strains), which followed a specified strain history, was used as an input signal to control the horizontal principal stress. The horizontal principal stress was, in turn, used
44、 to control the vertical principal stress such that they were always equal in magnitude and opposite in direction. The hysteretic loops of the two panels, CA3 and CE3, are shown in Fig. 2 (a) and (b), respectively. In these figures, the vertical and horizontal axes represent the shear stress T and t
45、he shear strain y45. at 45 degrees to the principal coordinate of applied stresses. In Fig. 2 (a), the hysteretic loops of panel CA3 displayed a highly pinched shape that are generally associated with shear dominated behavior. The envelope curve of this panel also exhibited a distinct descending bra
46、nch indicating a severe strength degradation of the panel with increasing shear strain magnitude. In contrast, no pinching effect was observed in Fig. 2 (b) for the hysteretic loops of panel CE3, with its steel grid parallel to the applied principal stresses. The envelope curve of panel CE3 did not
47、have a descending branch and the strength deterioration was not noticeable. CYCLIC SOFTENED MEMBRANE MODEL (CSMM) In the basic concept of CSMM, the cracks are smeared throughout the reinforced concrete elements, and the reinforcing bars are uniformly distributed in two orthogonal directions (P and t
48、). The behavior of the panels is, therefore, formulated in terms of smeared (average) stresses and smeared (average) strains, and the continuum mechanics can be applied. The equilibrium equations, compatibility equations, and the material constitutive models are summarized in this paper: Equilibrium
49、 Equations: up = u; cos2 a2 +u; sin2 a2 + riH 2sina, cosa2 + p,f, u, = a; sin2 az + afr cos a, - r + afr )sin a2 cos a2 + r;H (cos2 a2 - sin2 az ) (1) (2) (3) Compatibility Equations: (4) (5) E, =cosa+sina, +-2sina,cosa, Y VH 2 2 E, =,sina,+coa, -2sina,cosa, YVH Concrete: Material Science to Application 5 (6) Ycr = (-EY + EH )sin a2 cos a2 + - YW (cos2 a2 - sin2 a2) 2 2 where the symbols are given in the list of Notations. The constitutive laws of steel bars and concrete are summarized in the following sections. I Constitutive R
