PVA and PVA-ECC has been widely studied by university researchers worldwide. Here is a list of just some of the relevant published research (articles will download as a PDF):
Large Volume, High-Performance Applications of Fibers in Civil Engineering
This article presents an overview of fiber applications in cementitious composites. Current FRC applications are summarized, and the where, how, and why fibers are used in these applications, are documented. An actual case study involving a tunnel lining constructed in Japan is given to illustrate how a newly proposed structural design guideline takes into account the load carrying contribution of fibers. Composite properties related to structural performance are described for a number of FRCs targeted for use in load carrying structural members. Structural applications of FRCs are currently under rapid development. In coming years, it is envisioned that the ultra-high performance FRC, with ductility matching that of metals, will be commercially exploited in various applications.
Durable Overlay Systems with Engineered Cementitious Composites (ECC)
This paper reviews recent research on the application of an engineered cementitious composite (ECC) as overlay in the repair of deteriorated concrete structures. ECC is a highly ductile fiber-reinforced, cement-based composite, that has metal-like features when loaded in tension. The uniaxial tensile stress-strain curve shows a ‘yield’ point, followed by strain-hardening up to several percent strain, resulting in a material ductility of at least two orders of magnitude higher in comparison to normal concrete or standard fiber reinforced concrete. ECC also has unique cracking behavior. When loaded to beyond the elastic range, ECC maintains crack width to below 100 µm, even when deformed to several percent tensile strain. Experimental testing of ECC overlay reveals significant improvements in load carrying capacity and in system ductility over conventional concrete or steel fiber reinforced concrete overlays. The commonly observed overlay system failures by delamination or by spalling are eliminated when ECC is applied. Numerical simulation of differential drying shrinkage also confirms the superior performance of ECC. In the presence of a vertical joint, large crack formation and/or delamination are observed in mortar and fiber reinforced concrete overlays. These failure modes are suppressed when ECC is used as the overlay material. The unique material behavior of ECC makes it an powerful candidate material for durable overlay applications.
Reflections on the Research and Development of Engineered Cementitious Composites (ECC)
Excellent survey article. Here are some excerpts:
There is increasing evidence that a crack width of 100 micron represents a threshold above which water flow through cracks becomes appreciable. Since the crack width of ECC can be kept below this limit (Figure 14), it is likely that ECC would serve as an excellent "concrete-cover" in R/ECC structures. The low transport rate of aggressive agents through ECC may delay steel corrosion leading to extended service life in, e.g. structures in coastal regions…ECC may lead to enhanced construction productivity in several ways. The most direct means is by elimination of labor-intensive installation of shear reinforcing bars in seismic structures. The high shear capacity of ECC decreases or even eliminates the need for shear reinforcement.
Advances in ECC Research
This article reviews the recent advances in the research of Engineered Cementitious Composites (ECC), a class of micro-structurally tailored fiber reinforced cementitious composites. The design basis, the processing routes, and some ECC performance characteristics in structural applications are highlighted.
Reinforced ECC - An Evolution from Materials to Structures
Design techniques for using PVA-ECC with steel reinforcement
The presented research activities on ECC, the interaction of ECC with structural reinforcement, and on the deformation behavior of reinforced ECC flexural members under reversed cyclic loading conditions have shown that the combination of ECC with structural reinforcement leads to significant improvements of their structural performance as compared to conventional reinforced concrete members.
Fracture Toughness of Microfiber Reinforced Cement Composites
These tests revealed that the PVA and RC fibers were able to effectively postpone microcrack formation, thereby delaying the localization of the failure crack. The PP fibers were not able to provide the same level of reinforcement.
Tensile Strain-Hardening Behavior of Polyvinyl Alcohol Engineered Cementitious Composite (PVA-ECC)
A high-performance polyvinyl alcohol fiber-reinforced engineered cementitious composite (PVA-ECC) was developed for structural applications under the performance driven design approach…The underlying reason of the distinctly different tensile behavior between normal fiber-reinforced concrete and PVA-ECC is highlighted by the comparison of complementary energy from their fiber bridging stress and crack opening curves.
Constitutive rheological control to develop a self-consolidating engineered cementitious composite reinforced with hydrophilic poly(vinyl alcohol) fibers
Self-compacting PVA-ECC. A self-consolidating engineered cementitious composite (ECC), which exhibits tensile strain-hardening behavior in the hardened state, while maintaining self-consolidating properties in the fresh state, has been developed by employing hydrophilic polyvinyl lalcohol (PVA) fibers.
Measuring and Modifying Interface Properties of PVA Fibers in ECC Matrix
A single fiber pullout test was used in this study to measure the bond properties of polyvinyl alcohol fibers that are available at various diameters in a mortar matrix.
Man-Made Respirable-Sized Organic Fibers: What Do We Know about Their Toxicological Profiles?
It was concluded that the diameter of most manufactured PVA fibers is approximately 10–16 _m, and therefore exceeds the criteria for respirable size (i.e., generally considered to be 3 _m for fiber counting purposes...The authors concluded that there was no difference in lung cancer risk between workers exposed to PVA fibers when compared to non-exposed workers.
Development of fiber-reinforced mortar (high performance or highly deformed FRC) to exhibit metallic (or pseudo-metallic) deformation
Endures deformation greater than that causing the failure of previous mortar by 200 times
Bending Response of Hybrid Ferrocement Plates with Meshes and Fibers
For ferrocement and laminated cementitious composites, increasing the number of mesh layers is not an efficient way to improve the modulus of rupture (MOR); moreover, at high reinforcement ratio severe spalling of matrix cover and delamination of extreme tensile layer are likely to lead to premature failure. Adding discontinuous fibers to the matrix provides a remedy to these drawbacks. In this paper, the bending response of hybrid ferrocement thin plates reinforced with meshes and fibers is reported and compared with conventional ferrocement composite with meshes and plain mortar...Compared with the specimens using plain mortar, the presence of fiber results in substantial increase in MOR, significant reduction in crack spacing and in turn crack width, prevention of cover spalling even at large deflection, and considerable improvement in shear capacity. An increase of the toughness and energy absorption to failure by up to 250% was also observed when a ductile fiber reinforced matrix was used with the FRP meshes.
Observing the Multiple Cracking of FRC Composites by Electronic Speckle Pattern Interferometry
Conclusion: Better fiber dispersion increases the toughness of the composite.
Summary of Findings and Recommendations of the JCI International Workshop on Ductile Fiber Reinforced Cementitious Composites (DFRCC)
The technical papers represented the state-of-the-art in DFRCC for infrastructure applications and aimed at indicating future research needs for the development and implementation of DFRCC to improve the performance of reinforced concrete buildings.
The use of extrusion rheometry in the development of extruded, fiber-reinforced composites
A discussion of the development of the use of PVA fibers to replace asbestos reinforcement in extruded thin-sheet cement board products.
Interface Tailering for Strain-Hardening Polyvinyl Alcohol-Engineered Cementitious Composites (PVA-ECC)
Research documents oiling of PVA fibers to achieve optimal 4% strain-hardening
JCI-DFRCC Summary Report on DFRCC Terminologies and Application Concepts
The paper attempts to summarize the terminologies related to DFRCCs and the structural advantages and application concepts of DFRCCs.
Mixing Effects of Different Sizes of Synthetic Fibers on Concrete
This is a not yet published article on the effects of mixing two different sizes of PVA fiber together to create a hybrid "fiber cocktail". The result of combining two fiber sizes was very effective, with significantly improved performance. Please send a request to receive this document to rmccabe@alumni.princeton.edu
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Strain-hardening means that PVA-ECC is dramatically stronger in tension than any regular or fiber-reinforced concrete.
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