Analysis of Compressive Toughness and Deformability of High Ductile Fiber Reinforced Concrete

Abstract

The compressive toughness evaluation index of HDC (high ductile fiber reinforced concrete) is studied through three groups of uniaxial compressive tests of HDC specimens with different fiber mixing amounts, and an equivalent analysis of their deformability is carried out, coming to the following conclusion:(1)the peak strain of HDC under uniaxial compression can be up to 3.41~3.67 times as large as that of the mortar matrix;(2)the equivalent compressive toughness index reflects the unit volume deformation energy of specimens under uniaxial compression and it can be used as the compressive toughness evaluation index of HDC;(3)the fiber bridging effect of HDC increases the equivalent compressive toughness index and the compressive deformability up to 3 times of the mortar matrix;(4)the relationship between the equivalent compressive toughness indexWcu0.85and the fiber mixing amountφis established according to the test results; and(5)the fiber bridging effect of the matrix in HDC can be equaling as a large number of constraint stirrups installed in the specimens, which significantly enhances the compressive toughness and the compressive deformability of specimens.

Uniaxial Compressive Test of High Ductile Fiber‐Reinforced Concrete and Damage Constitutive Model

“…Figure 5(c), the peak strain of specimens demonstrates a significant rise when the fly ash content increases from 40% to 50% and a slight reduction when the fly ash content increases from 50% to 60%, together with the ultimate compressive strain. e cause is that fly ash can improve the interfacial bond properties between fibers and matrix, thus preventing excessive fiber rupture and enhancing the toughness of HDC [1]. It should also be noted that the maximum stress declines with the increase in the fly ash content.…”

“…High ductile fiber-reinforced concrete (HDC) [1], just like engineered cementitious composites (ECCs) [2,3], is also a kind of high performance fiber-reinforced cementitious composite (HPFRCC) [4,5], which is composed primarily of cement, fine aggregate, and fiber. HDC is manufactured based on the designed theory of micromechanics and fracture mechanics and can be characterized by pseudostrain hardening and multiple cracking behaviors when subjected to tensile loading.…”

“…erefore, damage mechanics can be used to derive the constitutive model of HDC. e toughness and deformability of HDC under uniaxial compression can be significantly improved for the lateral restraint effect of the fiber bridging stress inside the matrix, which has obvious difference with concrete [1]. e researchers [21][22][23][24][25][26][27] primarily focused on the concrete and steel fiber-reinforced concrete, both of which can be classified as a brittle material.…”

Mechanical Properties of Desert Sand-Based Fiber Reinforced Concrete (DS-FRC)

“…They have the characteristics of higher tensile ductility and compression deformation properties, and the uniaxial tensile and compression strains can be over 3% and 0.5%, respectively [1,2]. Although, there are varieties of names such as engineered cementitious composites (ECC) [3,4], ultra-high performance fiber reinforced cementitious composites (UHPFRCC) [5,6], strain hardening cementitious composites (SHCC) [7][8][9], ultra-high toughness cementitious composites (UHTCC) [10][11][12] and fiber reinforced concrete (FRC) [13,14], they all maintain the essence of high ductility and have achieved good engineering applications [15][16][17][18][19]. The high ductility cementitious composites are composed of polyvinyl alcohol fiber (PVA) and fine aggregates, such as cement, fly ash, and fine river sand.…”

Seismic Performance of High‐Ductile Fiber‐Reinforced Concrete Short Columns

“…High-ductile fiber-reinforced concrete (HDC) [4,5] is a kind of fiber-reinforced cement composites like engineering cementitious composites (ECC) [6,7] and high-performance fiber-reinforced cement composites (HPFRCCs) [8,9], which shows steady propagation of multiple fine cracks and excellent tensile strain-hardening behavior due to the fiber-bridging effect [6]. ose materials provide a new method to solve the brittleness of concrete; thus, they have been paid more and more attention in structural engineering.…”