Mixed mode fracture resistance of asphalt concrete mixtures

An in-house finite element code was utilized to evaluate mode I/II stress intensity factor (SIF) of an edge cracked semi-circular disc subjected to three-point bending. The specimen was considered as an isotropic and homogeneous material. Relative span length ratios of 0.3 to 0.8 in steps of 0.1 were invoked. Relative crack length ratios of 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 were analyzed with crack angles up to 60° in steps of 5°. At the same crack length, mode I SIF decreases with increasing crack angle or decreasing the span length. The range of pure mode II decreases with increasing the span length. For the same crack length, the crack angle corresponding to the transition from a mixed mode I/II to a pure mode II increases with increasing the relative span length ratio. On the contrary, that angle decreases with increasing the crack length for the same span length. Good agreement has been generally obtained with relevant results found in the literature.

Section: Introductionmentioning

confidence: 99%

Numerical evaluation of mode I/II SIF of quasi-brittle materials using cracked semi-circular bend specimen

Fayed¹

2018

“…Erdogan & Sih (1963), Williams & Ewing (1972) and Theocaris (1984) used a rectangular plate containing an inclined center crack subjected to a uniform far field tension in their mixed mode fracture studies. The symmetric and asymmetrically loaded three or fourpoint bend specimens were also employed by researchers for investigating mode I and mixed mode brittle fracture (Fett et al, 1995;Xeidakis et al, 1996;Suresh et al, 1990, Aliha et al 2009Razavi et al, 2017Bahmani et al 2017;Heidari-Rarani et al, 2014), Disc type specimens including the centrally cracked Brazilian disk (BD) specimen, centrally cracked/notched ring specimen subjected to diametrall compression, edge notch disc bend (ENDB) and the semi-circular bend (SCB) specimen have been frequently employed for determining the mixed mode fracture resistance of various engineering materials such as rocks, graphite, concretes and polymers (Awaji & Sato, 1978;Ayatollahi et al, 2006;Ameri et al 2012Ameri et al ,2016Razmi & Mirsayar, 2017;Alhasan 2013;Fakhri et al 2017, Aliha et al 2008,2015a,c, 2017, Abd-Elhady 2013Al-Hdabi et al 2014;Dehghany et al 2017. However, some of these specimens have certain shortcomings.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of interfacial bond strength between Portland cement concrete and asphalt concrete layers using bi-material SCB test specimen

Mirsayar¹,

Shi²,

Zollinger³

2017

Portland cement concrete (PCC) / asphalt concrete (AC) bonded components are seen in both conventional pavement structures as well as overlays. Due to the environmental and traffic loads, cracks occur at the interface of the PCC and AC layers and finally, may propagate through the interface or one of the layers. Therefore, the evaluation of bond strength between these layers is important. This paper investigates bond strength between asphalt concrete and Portland cement concrete using a new sandwich test specimen. The developed specimen, called Bi-material semi-circular bend (BSCB) is made of asphalt concrete and the Portland cement concrete, cracked at the interface of the materials. First, the suggested specimen is introduced and characterized using finite element simulation. Then, the specimen is employed to obtain bond strength between asphalt concrete and Portland cement concrete under mixed mode loading, and at two temperatures: -20C and 20C. The fracture toughness at different mixed mode conditions is obtained, and finally, fracture criterion for the tested bonded joints is presented.

“…However, many of the fracture tests proposed by the previous researchers are not able to cover all mixed mode conditions. One can find several fracture test specimens in the literature such as compact tension (CT) specimen (Wagoner et al 2005, Kim et al 2014, wedge splitting (WS) test (Brühwiler et al, 1990;Issa et al, 2003), three point bend (3PB) specimen (Korte et al, 2014;Seitl et al, 2017;, four point bend (4PB) specimen (Munz et al, 1980;Razavi et al, 2017;Fakhri et al, 2017;Ayatollahi & Aliha 2011) , Brazilian disk (BD) specimen Wei et al, 2015;Akbardoost et al, 2014;Ayatollahi & Aliha, 2009a), semicircular bend (SCB) specimen (Funatsu et al, 2014;Wei et al, 2017ab;Ameri et al, 2012Ameri et al, , 2016Aliha & Fattahi Amirdehi, 2017), center cracked or notched ring specimen (Dehghany et al, 2017;, triangular bend (ECT) specimen , edge notch disc bend (ENDB) specimen (Bahmani et al, 2017;Tutluoglu & Keles, 2011;Aliha et al, 2015Aliha et al, , 2016, Diagonally loaded square plate (DLSP) specimen (Ayatollahi & Aliha, 2009b), and double cantilever beam (DCB) specimen (Ranade et al, 2014;Lopes et al, 2016). Fig.…”

Section: Fracture Criteria For Bonded Structuresmentioning

confidence: 99%

Factors influencing stresses and movements in continuously reinforced concrete pavements – A review

Mirsayar¹,

Zollinger²

2018

The use of cement concrete as a stronger and more durable material than asphalt concrete in construction of the pavements has been increased during the past decades. This review paper investigates the effect of various input variables for the design of continuously reinforced concrete pavements. A literature review is prepared based on the efforts performed by many researchers to investigate the effect of different factors including temperature change, shrinkage, material properties of the concrete, and concrete slab/ subbase bond properties on the displacements and stresses in the concrete slab. It is found that the important role of concrete slab/ subbase bond strength has not been investigated properly as compared to other input variables.