Interval Reliability Assessment of Reinforced Concrete Beam Placed on Elastic Foundation (Published)
The article proposes a formula to evaluate the reliability of the structure according to the interval model. In the case that the load effects and structural capabilities are sets of the form of interval numbers, the interval reliability evaluation formula is extended and established from the reliability in the stochastic model based on the probability geometric definition and the basic operations of interval arithmetic. Next, the paper presents a method to determine the internal force of a beam structure placed on an elastic foundation considering the uncertainty of the input parameter in the form of intervals. The finite element method combined with the interval function optimization algorithm is used to determine the interval output internal force of the beam structure. From that, the evaluation formula is applied to evaluate the reliability of reinforced concrete beam structure placed on elastic foundation with input parameters in the form of interval form: elastic modulus of material, concrete strength, and reinforcement strength, static load and Winkler’s foundation coefficient.
Citation: Duy Cong Lea and Hoa Quang Nguyenb (2021) Interval Reliability Assessment of Reinforced Concrete Beam Placed on Elastic Foundation, International Journal of Civil Engineering, Construction and Estate Management, Vol.9, No.3, pp.16-32
Keywords: Finite Element Method, beam on elastic foundation, elastic foundation, interval analysis, interval numbers, interval reliability of structures, reliability of structures
Analysis of Curved Plate Elements Using Open Source Software (Review Completed - Accepted)
Analysis of curved plate elements requires a high computational effort to obtain a reliable solution for a buckling load for design purposes. Available programs are expensive to acquire and they need thorough knowledge for effective use. There is therefore need to code cheaper and accessible programs in line with using sustainable methods to better the livelihood of mankind. To address this issue a theory is formulated based on the Euler-Bernoulli beam model. This model is applicable to thin elements which include plate and membrane elements.
This paper illustrates a finite element theory to calculate the master stiffness of a curved plate. The master stiffness takes into account the stiffness, the geometry and the loading of the element. The determinant of this matrix is established from which the buckling load which is unknown in the matrix is evaluated by the principal of bifurcation.
The curved element is divided into 2,3,6,9 and 12 elements; this demonstrates the computational effort to a reliable solution. As expected, that as you divide the curve into smaller constituent elements, the solution of the buckling load is tedious as more mathematical operations are involved hence the need to program the operations.
Numerical analysis is carried out by abstracting the procedural development of the theory and programming it to run in a visual basic platform. The results obtained are giving a good agreement with results obtained with classical plate equations. This program is proposed to increase computational efficiency in the analysis of curved plates at a sustainable cost. It can also be used to establish the relationship between buckling load and curvature of plates
Keywords: Analysis, Curved Plates, Finite Element Method, Program