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Pozzolan has been widely used as a supplementary cementitious material to improve concrete properties such as workability and shrinkage. Bagasse ash (BA) is an industrial waste that has pozzolanic properties like fly ash (FA), but its cost is relatively lower. Research conducted on concrete mixed with BA (CBA) were primarily on the properties of CBA, investigation on the bonding strength of steel rebars in CBA was still limited. This paper aims to investigate the effect of BA on the overall bonding strength of reinforced concrete using a pull-out testing method. Based on the range of the parameters considered in the present work, the results revealed that the bonding strength was inversely proportional to the BA content in concrete. The bonding strength of rebar in CBA was compared with that in ordinary cement concrete. It was found that the bonding strength of rebar in CBA was lower than that in concrete without BA at 28-day age. When the concrete age was more than 90 days, and BA content was not greater than 20% cement replacement, the difference in the bonding strength was insignificant. This outcome indicates that the current standard for designing the development length of rebars in CBA is still valid when the BA content is not greater than 20% of the cement. Further experiments are required to investigate any size effect. [ABSTRACT FROM AUTHOR]

The shakedown analysis of elastoplastic plane frames with semirigid connections is considered within a framework of discrete models and piecewise linear yield surfaces. The formulation adopted is based on the classical Bleich-Melan static theorem, and leads to a linear programming problem. A simple linear elastic perfectly plastic connection element is used to account for the reduced flexibility and partial strength of semirigid beam-to-column connections. The necessary conditions of equilibrium and of yield conformity are expressed compactly in matrix form, and the calculation of the elastic locus for the cyclic-load domain is clarified. A means of identifying whether incremental collapse or alternating plasticity governs failure under repeated loading is also mentioned. Finally, three examples are presented primarily as a preliminary assessment of the shakedown behavior of semirigid frames. In particular, it is shown that the shakedown limit of such structures can be significantly lower than the corresponding plastic collapse limit. The importance of considering axial effects on plasticity and of using the correct elastic stiffness in shakedown calculations are also highlighted.

Current silo analysis and design methods developed from Janssen's theory focus mainly on the flow of the granules inside the silo by assuming that the overall silo structure is infinitely rigid. A silo structure during discharge is technically a time varying mass dynamic problem, where the properties of the overall silo structure and the discharge rate and material properties also contribute to the development of the load. The physics of a silo system requires equilibrium between the granules inside the silo, the silo structure as a whole and the surrounding air. The established scientific principles and experimental data require fulfilling such equilibrium to accurately predict the dynamic loads during discharge. This correspondence explains how the equilibrium between the granules inside the silo, the silo structure as a whole and the surrounding air can be achieved to better predict and control the dynamic loads generated by the silo discharge process. [ABSTRACT FROM AUTHOR]