13 documents found, page 1 of 2
Shear resistance and cracking behaviour of SFRC beams with and without axial load
Ding Yining; Liu Hekai; Zhang Yulin; Ning Xiliang; Azevedo, Cecília MariaIn order to simulate and evaluate the fiber effect and the synergetic effect of the hybrid using of fibers and stirrups on the flexural shear resistance and diagonal cracking behavior of tunnel segment, a series experiments has been conducted. Different from the conventional testing method, the symmetric inclined beams subjected to combined action of flexure, shear and axial compression were used for simulating...
About birnbaum-saunders distributions based on the Johnson system
Athayde, Emilia; Azevedo, Cecília Maria; Leiva, Víctor; Sanhueza, AntonioIn this article, we study Birnbaum–Saunders distributions based on the Johnson system including the case of a location-scale model. We mainly focus our attention on a four-parameter Birnbaum–Saunders distribution, since it contains all the versions presented here as particular cases. We describe structural aspects of this distribution considering its basic indicators, such as the density, distribution and quant...
Study on residual behaviour and flexural toughness of fibre cocktail reinforced...
Ding, Yining; Azevedo, Cecília Maria; Aguiar, J. L. Barroso de; Jalali, SaidThis paper analyzed the effect of different fibres on the residual compressive strength, the ultimate load and flexural toughness, the failure pattern and the fracture energy of self compacting high-performance concrete (SCHPC) after exposure to various high temperature. The micro polypropylene fiber (PP fiber) could mitigate the spalling of SCHPC member significantly, but did not show clear effect on the mecha...
Shape and change point analyses of the Birnbaum-Saunders-t hazard rate and asso...
Azevedo, Cecília Maria; Athayde, Emilia; Leiva, Víctor; Balakrishnan, N.The hazard rate is a statistical indicator commonly used in lifetime analysis. The Birnbaum-Saunders (BS) model is a life distribution originated from a problem pertaining to material fatigue that has been applied to diverse fields. The BS model relates the total time until failure to some type of cumulative damage that is normally distributed. The generalized BS (GBS) distribution is a class of positively skew...
Hybrid use of steel and carbon-fiber reinforced concrete for monitoring of crac...
Ding, Yining; Han, Z.; Zhang, Y.; Azevedo, Cecília MariaIn order to study the damage after concrete cracking, the influence of the combined use of steel fiber and carbon fiber on the conductivity and crack resistance of concrete beam under flexural loading were investigated. Carbon fiber and steel fiber were added as diphasic conductive materials to produce the electric conductive and ductile concrete. This paper reports the experimental and analytical work associat...
Combined effect of steel fibres and steel rebars on impact resistance of high p...
Ding, Yining; Chen, Xiang-yu; Azevedo, Cecília MariaThe investigation on the impact properties of normal concrete (NC)and reinforced concrete (RC) specimens, steel fibre reinforced concrete (SFRC) specimens and RC+SFRC specimens with different steel fibres dosages were carried out with the drop-weight impact test recommended by ACI Committee 544. The results indicate that the number of blows to final failure greatly increased by addition of steel fibres. Moreove...
Modeling wind energy flux by a Birnbaum-Saunders distribution with an unknowm s...
Leiva, Víctor; Athayde, Emilia; Azevedo, Cecília Maria; Marchant, CarolinaIn this paper, we discuss a Birnbaum–Saunders distribution with an unknown shift parameter and apply it to wind energy modeling.We describe structural aspects of this distribution including properties, moments, mode and hazard and shape analyses.We also discuss estimation, goodness of fit and diagnostic methods for this distribution. A computational implementation in R language of the obtained results is provid...
On the kernel estimation of a multivariate distribution function under positive...
Azevedo, Cecília Maria; Oliveira, Paulo E.In this paper, we consider the kernel estimator of the p-dimensional marginal distribution function of a stationary, positively associated sequence of random variables. For this setting, we state results concerning the asymptotic behaviour of this estimator extending some characterizations available in the literature. In addition, we present a simulation study about the empirical process constructed from such a...
A note on convergence rates in the strong law of large numbers for associated s...
Azevedo, Cecília MariaLet $X_n,\,n\in \N$, be a strictly stationary sequence of centered and associated real random variables. Sufficient conditions for the strong law of large numbers to hold are known, but no rates of convergence where given. We derive an upper bound for this convergence rate. This rate is made explicit for geometrically decreasing covariances.
On the multivariate kernel distribution estimator for distribution functions un...
Azevedo, Cecília Maria; Oliveira, Paulo E.In this note we consider the estimation of the multivariate distribution function Fp of the p-dimensional marginal of a stationary associated sequence. We show, under certain regularity conditions, the almost sure consistency and characterize the asymptotic behavior of the MSE. We also characterize the asymptotic optimal bandwidth. Under some stronger assumptions on the covariance this bandwidth rate is shown t...