The wedge splitting test specimens with three series of different relative crack length were used to study the influences of relative crack length on the fracture toughness of common concrete. The suitable formulation for fracture toughness of concrete with different relative crack length was gotten on comparing between fracture toughness test results and computation results of the model developed from Hu formula.
Eleven 4-phenylcoumarins including three new 4-phenylcoumarins, mesuaferols A-C (1-3), together with eight known 4-phenylcoumarins (4-11) have been isolated from the flowering buds of Mesua ferrea. Their structures were established on the basis of extensive analyses of HR-ESI-MS, UV, IR, and NMR spectral data, as well as by comparison of their spectral data (including CD spectra) with those reported in the literature. The cytotoxicity of isolated compounds against MDA-MB-231, MCF-7, HepG2 and HeLa cell lines was evaluated. Compound 9 showed moderate cytotoxicity against MDA-MB-231, MCF-7, HepG2 and HeLa cell lines with IC 50
Chloride ion penetration and freezing and thawing damage are the two main factors that affect the durability of concrete structures. Through the chloride ion penetration test and freezing and thawing test of concrete specimens after tensile and compressive loading, the influence of load-induced damage on the long-term durability of concrete was studied. The results showed that the apparent chloride diffusion coefficient of concrete increased by 6.4% and 34%, and the surface chloride concentration increased 10% and 40%, respectively, both of which showed the "negative effect" when the uniaxial tensile load level reached the 65% and 75% of the ultimate capacity. However, with the increasing uniaxial compressive load level, the impact on the frost resistance of concrete experienced a transformation from the "positive effect" to the "negative effect".
The numerical simulation of reinforced concrete deep beams with opening is analyzed by Finite Element Software ANSYS to establish reasonable mechanical model. The stress characteristics and deformation's situation of the deep beams with opening are in analyzed under concentrated load and different openings in different parts. The purpose is to supply some favorable suggestions in engineering application of reinforced concrete deep beam with openings.
Keywords-deep beams with opening; force performance; the finite element; calculation analysisI.
An experiment was done to study the impact which SCC reinforced by different volume fraction has on CBF in the relative increase of splitting-tensile strength, splitting toughness and flexural toughness. The findings were that the more the fiber volume, the more increase of the splitting toughness. When the volume was 1.2‰, the splitting tensile strength of 28d and 60d reached its maximum; SCC tension increased with the increase of the volume of CBF; when the CBF was added, the flexural load-displacement curves of SCC became not so sharp, thus having an apparent impact on the toughness of SCC.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.