The optimal design of a twenty-five bar space truss commonly involves multiple loading conditions acting on 4 node elements in the linear elastic model. In this paper, we describe the behavior of the truss system with our experimental loading conditions on five node elements subject to minimum displacement and stresses that are used to formulate the constrained nonlinear optimization problem. Numerical computations are developed with the objective of mass minimization and the best structural design is selected by applying the interior point method with the guidance of Matlab Optimization Toolbox. Our numerical results show the optimal values of cross-sectional areas, material densities, and internal forces which satisfy the minimum weight design. These results provide the appropriate mass to the experimental data and allow substantial changes in size, shape, and topology.

BIM (building information modelling) is transforming the architecture, engineering, and construction (AEC) industry all around the world

In this paper, we compare computational design of box culverts using Kleinlogel’s formulas and three-dimensional models based on Winkler and Modified Vlasov Foundation (MVF) by Radial Point Interpolation method (RPIM) . In order to extend the RPIM to the study of box culverts, a method of decomposition by subdomain and a creation of a fictitious rotation is made. Similar results are observed between the RPIM_Winkler and STAAD PRO (FEM software) with fewer nodes in the case study. The Kleinlogel’s formulas or the Winkler model gives a maximal increase in stresses at the middle of the raft of 5%, and a 12 times increased displacement. Finally, it emerges that for the same type of soil and a single structure, the reaction and shear modulus of the soil are highly dependent on the distribution of loads on the structure.

Toward Preventive Maintenance and Rehabilitation of Bridges in Cameroon

With the on-growing construction of transport and communication structures in rural and urban zones due to economic requirements, and with occurrence of seismic events in past years in particular in Cameroon, one of the purposes of the present work is to display the feasibility and advantages of applying active tendon control strategy to a bridge structure. The ‘Linearization of Feedback Gain Matrix’ (LFGM) method proposed by the author to achieve this objective is obtained by activating some useful components of the Riccati matrix while others are strongly attenuated according to the expected output-results and requirements of control mechanism. The present algorithm is helpful for any user to obtain full vibration suppression if the imposed linearization proportionality coefficients are constantly modified to optimal values. Comparing with traditional methods, the efficiency of the proposed linearization is more compatible to the control of civil structures and has many advantages according to simulation results obtained through sinusoidal and earthquake excitations. Keywords: Vibration control, bridge, matrix linearization, construction, responses