MATHEMATICAL MODELING OF THE COVERING OPTIMIZATION OF THE ROUND BUILDINGS IN A PLAN WITH A RADIAL BEAM POSITION

The article presents the results of optimization of the angle between radial beams in the floor of a circular building in the plan. On the one hand, they rest on the central post, and on the other, on vertical supporting structures along the circle. Steel decking is laid on the beams. The angle between the beams is determined so that the mass of the beam and the deck is minimal. This angle is considered optimal. To solve the problem, the target function of the cost of flooring and radial beams per unit floor area is used. This function depends on the angle between the beams. Using mathematical methods of differentiation, the minimum of the objective function and the corresponding value of the optimal angle were found. The thickness of the flooring was determined on the basis of ensuring its rigidity. It is assumed that composite welded radial beams have I-beams with two axes of symmetry. The height of the beam corresponds to the equality of the areas of the shelves and the wall. The problem of determining the optimal angle between the beams was solved on the basis of ensuring the strength of the beams under normal stresses. In the design diagram of the beam, a triangular distributed load is adopted. The dimensions of the cross-section of the beam were determined based on the equality of the required and actual moments of resistance, and were included in the target cost function. The study took into account that the deflection of the beam at the optimal angle between them can exceed the limiting standard value. Based on the solution of the system of equations of strength and stiffness, a formula is obtained for the minimum angle between the beams from the stiffness condition. The carried out mathematical studies have shown that at the optimal angle between the beams, it is possible to ensure its rigidity. This is possible when the flexibility of the beam wall exceeds a certain minimum value. Analysis of the formula for the minimum value of the wall flexibility showed that it is proportional to the design steel resistance to the sixth power. Therefore, to ensure that the deflection of the beam does not exceed the limiting value at the optimum angle, it is necessary to use low strength steel. To confirm the practical feasibility of using the proposed method, the problem was solved with certain numerical data. The results obtained have confirmed that the problem has a practical meaning at a relatively low steel strength. In addition, it turned out that the optimal angle between the beams does not depend on its span.

Wind Load Analysis on A Multistoreyed Building Curved in Plan

: In this study a tall G+8 storied curved in plan (comprising an external and internal curved facade) has been analysed for wind acting in specified directions using STAAD pro v8i.For the curved profile, the wind load component has been calculated for each radial beam line. The combination of static load and wind load are taken into consideration. In the first case, the wind has been assumed to act towards the centre of the arc of the circle and in the second, away from the centre. The post processing reverberation in terms of bending moments, shear forces and support reactions has been studied in relation to the wind directions. Due to the effect of wind load on the structure, the storey-sage variation of the result with respect to different parameters are to be compared. The stiffness of the structure as a whole is expected to vary with the changed direction of the wind. The result would result in a parametric study of the effect of wind direction on curved profile. The orientation of the curved structure with respect to the direction of wind load has been studied.

Improving Data Quality for the Australian High Frequency Ocean Radar Network through Real-Time and Delayed-Mode Quality-Control Procedures

Quality-control procedures and their impact on data quality are described for the High-Frequency Ocean Radar (HFR) network in Australia, in particular for the commercial phased-array (WERA) HFR type. Threshold-based quality-control procedures were used to obtain radial velocity and signal-to-noise ratio (SNR), however, values were set through quantitative analyses with independent measurements available within the HFR coverage, when available, or from long-term data statistics. An artifact removal procedure was also applied to the spatial distribution of SNR for the first-order Bragg peaks, under the assumption the SNR is a valid proxy for radial velocity quality and that SNR decays with range from the receiver. The proposed iterative procedure was specially designed to remove anomalous observations associated with strong SNR peaks caused by the 50 Hz sources. The procedure iteratively fits a polynomial along the radial beam (1-D case) or a surface (2-D case) to the SNR associated with the radial velocity. Observations that exceed a detection threshold were then identified and flagged. After removing suspect data, new iterations were run with updated detection thresholds until no additional spikes were found or a maximum number of iterations was reached.