Fatigue Performance Test and Life Calculation of Fiber-Reinforced Asphalt Concrete

Chip seal is most frequently used as preventive maintenance (PM) treatments on asphalt pavement. However, it’s difficult to make the performance test of chip seal in laboratory. In this paper, the specimen molding method of chip seal is established in laboratory. Firstly, considering the structure and technique condition of the original pavement, a cushion layer of asphalt concrete (AC) is used as under layer of the specimen. Secondly, the construction process of chip seal is simulated in laboratory, which includes spraying emulsified asphalt and/or glass fiber, spreading aggregate, initial rolling and conservation, post-stage rolling and conservation in interval for some time. Lastly, visual inspection and sand patch test are used to evaluate the quality of the specimen. Research results show that the method of specimen molding and test in laboratory could relatively accurately simulate, evaluate and forecast the performance of the chip seal.

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Fatigue performance of nanoclay filled glass fiber reinforced hybrid composite laminate

10.51415/10321/2464 ◽

2017 ◽

Author(s):

◽

John Olumide Olusanya

Keyword(s):

Fatigue Life ◽

Service Life ◽

Glass Fiber ◽

Residual Strength ◽

Composite Structures ◽

Fatigue Performance ◽

Fiber Reinforced ◽

Fiber Reinforced Composite ◽

Reinforced Composite ◽

Glass Fiber Reinforced

In this study, the fatigue life of fiber reinforced composite (FRC) materials system was investigated. A nano-filler was used to increase the service life of the composite structures under cyclical loading since such structures require improved structural integrity and longer service life. Behaviour of glass fiber reinforced composite (GFRC) enhanced with various weight percentages (1 to 5 wt. %) of Cloisite 30B montmorillonite (MMT) clay was studied under static and fatigue loading. Epoxy clay nanocomposite (ECN) and hybrid nanoclay/GFRC laminates were characterised using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The mechanical properties of neat GFRC and hybrid nanoclay/GFRC laminates were evaluated. Fatigue study of the composite laminates was conducted and presented using the following parameter; matrix crack initiation and propagation, interfacial debonding, delamination and S–N relationship. Residual strength of the materials was evaluated using DMA to determine the reliability of the hybrid nanoclay/GFRC laminates. The results showed that ECN and hybrid nanoclay/GFRC laminates exhibited substantial improvement in most tests when compared to composite without nanoclay. The toughening mechanism of the nanoclay in the GFRC up to 3 wt. % gave 17%, 24% and 56% improvement in tensile, flexural and impact properties respectively. In the fatigue performance, less crack propagations was found in the hybrid nanoclay/GFRC laminates. Fatigue life of hybrid nanoclay/GFRC laminate was increased by 625% at the nanoclay addition up to 3 wt. % when compared to neat GFRC laminate. The residual strength of the composite materials revealed that hybrid nanoclay/GFRC showed less storage modulus reduction after fatigue. Likewise, a positive shift toward the right was found in the tan delta glass transition temperature (Tg) of 3 wt. % nanoclay/GFRC laminate after fatigue. It was concluded that the application of nanoclay in the GFRC improved the performance of the material. The hybrid nanoclay/GFRC material can therefore be recommended mechanically and thermally for longer usage in structural application.

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