Comparison of fracture toughness values of normal and high strength concrete determined by three point bend and modified disk-shaped compact tension specimens

Abstract

ABSTRACT. The modified disk shaped compact tension test is a configuration derived from standard compact tension test that is used for measuring fracture mechanical properties of primarily metallic materials. The compact tension configuration is commonly used for measurement fracture mechanical properties as e.g. fracture toughness, Young's modulus, work of fracture etc. The modified compact tension tests imply significant modifications of the specimen morphology in order to avoid premature failure. The modified compact tension test is not proper for quasi-brittle materials due to its complicated shape (steel-concrete interface), but it is easily extracted from drill core and we do not need large amount of material for obtaining fracture properties as we need for e.g. three-or four-point bend test. Since it is a new test method, a wide range of tests is needed to be done before it can be applied. In the paper the selected outputs of the experiments performed on normal and high strength concrete will be processed and the values of fracture mechanical parameters will be discussed.

Fracture toughness on compact tension specimen as a quality parameter for cement stone

“…With Weibull modules of 5.1 and 6.0 the scatter of the fracture toughness is a little higher than the compression strength results with standard edge length of 40 mm. In comparison to fracture toughness tests on concrete and mortar specimens from other researches [8,9,10], the use of smaller specimen sizes in this study is advantageous in terms of reducing the amount of material required for testing. Additionally, the smaller specimens allow for testing under microscopic observation, which can provide valuable information about crack propagation details.…”

“…Strength is a parameter that comprises the fracture toughness and the defects in the tested volume. Toughness of concrete has been analyzed experimentally and numerically on many different specimen geometries, including notched beams and disc-shaped compact tension specimens [8,9,10]. However, the material cost due to the specimen size is just as great, if not greater than the original prisms for testing compressive strength of cement.…”

Mixed-mode fracture analysis in high-performance concrete using a Brazilian disc test

“…This geometry effect was recently discussed for lime stone, 23 for C 50/60, 16 for normal strength concrete (NSC) and high-strength concrete (HSC). 24 To evaluate the fracture resistance curve of the HPC under the mixed I/II, BDCN specimens were tested with various inclination angles a. The measured values of the fracture force Pc and the corresponding evaluated values of SIFs for mode I -K I and for mode II -K II are presented in Figure 2.…”

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

“…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.…”