In this study, a sustainable mortar mixture is developed using renewable by-products for the enhancement of mechanical properties and fracture behavior. A high-volume of fly ash—a by-product of coal combustion—is used to replace Portland cement while waste by-products from the production of engineered bamboo composite materials are used to obtain bamboo fibers and to improve the fracture toughness of the mixture. The bamboo process waste was ground and size-fractioned by sieving. Several mixes containing different amounts of fibers were prepared for mechanical and fracture toughness assessment, evaluated via bending tests. The addition of bamboo fibers showed insignificant losses of strength, resulting in mixtures with compressive strengths of 55 MPa and above. The bamboo fibers were able to control crack propagation and showed improved crack-bridging effects with higher fiber volumes, resulting in a strain-softening behavior and mixture with higher toughness. The results of this study show that the developed bamboo fiber-reinforced mortar mixture is a promising sustainable and affordable construction material with enhanced mechanical properties and fracture toughness with the potential to be used in different structural applications, especially in developing countries.

High-performance fiber-reinforced cement-based composite (HPFRCC) is a class of construction materials that exhibit pseudo-strain hardening behavior under tension after first cracking and gradual softening behavior under compression after crushing. Compared to conventional concrete, the enhanced tension and compression performance make HPFRCC promising for earthquake-resistant structures. Extensive studies have explored the seismic performance of reinforced HPFRCC with different material designs and in different structural forms, while real-world applications are emerging. This paper is intended to summarize the collective knowledge that the research community has gained and to identify future research needs. We review (1) HPFRCC cyclic performance on the material level, (2) seismic performance of reinforced HPFRCC flexural members, including beams and columns, (3) shear-dominant members, covering coupling beams and structural walls, and (4) the behavior and design of HPFRCC beam-column joints. We conclude with key challenges and opportunities for the research and professional community.

A numerical model that uses a nonlinear cracked hinge was developed to characterize the flexural behavior of a beam element composed of hybrid fiber-reinforced concrete (HyFRC). Deflection hardening performance criteria were established based on an average tensile strain capacity of 0.002 and a deterministic sensitivity analysis of the model. A HyFRC mix design is proposed that exceeds these performance criteria. The HyFRC flexural behavior and its flexural stiffness are compared against conventional reinforced concrete. Implications of the material flexural performance on performance-based structural design methods are discussed.

A singular hybrid finite element with seven nodes and triangular shape is used to determine the stress intensity factors for the splitting tension test. For different types of marble the finite-element simulations were used to compute the fracture toughness values. The small-grained marble types exhibit a high fracture toughness and stable crack growth. The smallest toughness was obtained for the coarse grained Georgia marble.