Effect of drying conditions on autogenous shrinkage in ultra-high performance concrete at early-age

This experimental study investigated the effects of drying conditions on the autogenous shrinkage of ultra-high performance concrete (UHPC) at early-ages. UHPC specimens were exposed to different temperatures, namely, 10, 20 and 40°C under a relative humidity (RH) ranging from 40 to 80%. The effects of using a shrinkage-reducing admixture (SRA) and a superabsorbent polymer (SAP) as shrinkage mitigation methods were also investigated. The results show that autogenous and drying shrinkage are dependent phenomena. Assuming the validity of the conventional superposition principle between drying and autogenous shrinkage led to overestimating the actual autogenous shrinkage under drying conditions; the level of overestimation increased with decreasing RH. Both SRA and SAP were very effective in reducing autogenous shrinkage under sealed conditions. However, SRA was efficient in reducing drying shrinkage under drying conditions, while SAP was found to increase drying shrinkage. Generally, results indicate that adequate curing is essential for reducing shrinkage in UHPC even when different shrinkage mitigation methods are applied.

[1]  Jeffrey J. Thomas,et al.  Effect of hydration temperature on the solubility behavior of Ca-, S-, Al-, and Si-bearing solid phases in Portland cement pastes , 2003 .

[2]  Rachel J. Detwiler,et al.  Reaction kinetics of portland cement mortars hydrated at different temperatures , 1992 .

[3]  Rachel J. Detwiler,et al.  Backscattered electron imaging of cement pastes cured at elevated temperatures , 1995 .

[4]  Zhichao Liu,et al.  Autogenous Shrinkage of Concrete with Super-Absorbent Polymer , 2009 .

[5]  P. Acker.  Swelling, shrinkage and creep: a mechanical approach to cement hydration , 2004 .

[6]  F. Lea.  The chemistry of cement and concrete , 1970 .

[7]  J L Hartmann,et al.  Construction of an Optimized UHPC Vechicle Bridge , 2005 .

[8]  Gaurav Sant,et al.  Interactions between shrinkage reducing admixtures (SRA) and cement paste's pore solution , 2008 .

[9]  Erika Holt,et al.  Contribution of mixture design to chemical and autogenous shrinkage of concrete at early ages , 2005 .

[10]  Sidney Diamond,et al.  Reaction products of densified silica fume agglomerates in concrete , 2004 .

[11]  A. Leemann,et al.  Shrinkage and restrained shrinkage cracking of self-compacting concrete compared to conventionally vibrated concrete , 2009 .

[12]  A. Loukili,et al.  Hydration kinetics, change of relative humidity, and autogenous shrinkage of ultra-high-strength concrete , 1999 .

[13]  P. Freiesleben Hansen,et al.  AUTOGENOUS DEFORMATION AND CHANGE OF THE RELATIVE HUMIDITY IN SILICA FUME-MODIFIED CEMENT PASTE , 1996 .

[14]  C. T. Tam,et al.  EFFECT OF WATER-TO-CEMENTITIOUS MATERIALS RATIO AND SILICA FUME ON THE AUTOGENOUS SHRINKAGE OF CONCRETE , 2003 .

[15]  Konstantin Kovler,et al.  Overview and Future Trends of Shrinkage Research , 2006 .

[16]  Konstantin Kovler,et al.  Why Sealed Concrete Swells , 1996 .

[17]  F. H. Wittmann,et al.  Creep and shrinkage in concrete structures , 1982 .

[18]  Dale P. Bentz,et al.  Reducing Thermal and Autogenous Shrinkage Contributions to Early-Age Cracking , 2008 .

[19]  Oskar Esping.  Early age properties of self-compacting concrete - Effects of fine aggregate and limestone filler , 2007 .

[20]  D. Bentz.  Influence of Shrinkage-Reducing Admixtures on Early-Age Properties of Cement Pastes , 2006 .

[21]  D. Bentz,et al.  Shrinkage-reducing admixtures and early-age desiccation in cement pastes and mortars , 2001 .

[22]  E. Brühwiler,et al.  Development of the mechanical properties of an Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) , 2006 .

[23]  F. Škvára,et al.  The effect of water ratio on microstructre and composition of the hydration products of portland cement pastes , 2002 .

[24]  John Forbes Olesen,et al.  Influence of Cement Particle‐Size Distribution on Early Age Autogenous Strains and Stresses in Cement‐Based Materials , 2001 .

[25]  Laurent Frouin,et al.  Microstructural analysis of RPC (Reactive Powder Concrete) , 1995 .

[26]  Pierre-Claude Aitcin,et al.  DEMYSTIFYING AUTOGENOUS SHRINKAGE , 1999 .

[27]  O. Jensen,et al.  Water-entrained cement-based materials: II. Experimental observations , 2002 .

[28]  C. Poon,et al.  Degree of hydration and gel/space ratio of high-volume fly ash/cement systems , 2000 .

[29]  E. Tazawa.  Autogenous Shrinkage of Concrete , 1999 .

[30]  A. Almusallam,et al.  Effect of environmental conditions on the properties of fresh and hardened concrete , 2001 .

[31]  Pietro Lura,et al.  Autogenous Deformation and Internal Curing of Concrete , 2003 .

[32]  Vtt Publications,et al.  Early age autogenous shrinkage of concrete , 2001 .

[33]  Jong Herman Cahyadi,et al.  Effects of densified silica fume on microstructure and compressive strength of blended cement pastes , 2003 .

[34]  Edward J. Garboczi,et al.  Percolation of phases in a three-dimensional cement paste microstructural model , 1991 .

[35]  D. Bentz,et al.  Drying/hydration in cement pastes during curing , 2001 .

[36]  P. Hewlett,et al.  Lea's chemistry of cement and concrete , 2001 .

[37]  Per Freiesleben Hansen,et al.  Influence of temperature on autogenous deformation and relative humidity change in hardening cement paste , 1999 .

[38]  Josef Kaufmann,et al.  Effect of the addition of ultrafine cement and short fiber reinforcement on shrinkage, rheological and mechanical properties of Portland cement pastes , 2004 .

[39]  Will Hansen,et al.  Investigation of blended cement hydration by isothermal calorimetry and thermal analysis , 2005 .

[40]  Kenji Kawai,et al.  Autogenous shrinkage of high-strength concrete containing silica fume under drying at early ages , 2005 .

[41]  Ahmed Loukili,et al.  Autogenous deformations of cement pastes: Part II. W/C effects, micro–macro correlations, and threshold values , 2006 .

[42]  Pietro Lura,et al.  Performance of Shrinkage-Reducing Admixtures at Different Humidities and at Early Ages , 2008 .

[43]  F. Stallmach,et al.  Water balance and pore structure development in cementitious materials in internal curing with modified superabsorbent polymer studied by NMR , 2009 .

[44]  P. Lura,et al.  Measuring techniques for autogenous strain of cement paste , 2007 .

[45]  M. Pigeon,et al.  Influence of key parameters on drying shrinkage of cementitious materials , 1999 .

[46]  Ahmed Loukili,et al.  Predicting Ca(OH)2 content and chemical shrinkage of hydrating cement pastes using analytical approach , 2004 .

[47]  D. Cusson,et al.  An experimental approach for the analysis of early-age behaviour of high-performance concrete structures under restrained shrinkage , 2007 .

[48]  A. Ehrlacher,et al.  Analyses and models of the autogenous shrinkage of hardening cement paste: I. Modelling at macroscopic scale , 1995 .

[49]  Frank Winnefeld,et al.  Effect of temperature on the pore solution, microstructure and hydration products of Portland cement pastes , 2007 .

[50]  S. A. Al-Saleh,et al.  Effects of drying conditions, admixtures and specimen size on shrinkage strains , 2006 .

[51]  Erika Holt,et al.  Cracking risks associated with early age shrinkage , 2004 .

[52]  Sidney Diamond,et al.  Densified silica fume: particle sizes and dispersion in concrete , 2006 .

[53]  Eugen Brühwiler,et al.  Thermo-mechanical Response of UHPFRC at Early Age—Experimental Study and Numerical Simulation , 2008 .

[54]  Will Hansen,et al.  Drying Shrinkage Mechanisms in Portland Cement Paste , 1987 .

[55]  Xiao Wen,et al.  Drying Shrinkage of Cement-Based Materials Under Conditions of Constant Temperature and Varying Humidity , 2007 .

[56]  John H. Sharp,et al.  The effect of temperature on the early hydration of Portland cement and blended cements , 2000 .

[57]  P. Lura,et al.  Superabsorbent Polymers — An Additive to Increase the Freeze-Thaw Resistance of High Strength Concrete , 2007 .

[58]  C. Nmai,et al.  Shrinkage-Reducing Admixtures , 1998 .

[59]  Per Freiesleben Hansen,et al.  Water-entrained cement-based materials , 2001 .