Topology Optimization Based Approach For Design Of A Hydraulic Steel Radial Gate With Two Oblique Arms

Water gate is an important facility in hydraulic engineering to control the water level inchannels or reservoirs. Hydraulic gates can be classified into many types according to theshape of the water retaining face plate of gates. Radial gates are very popular because of theirmany merits, e.g., easy operating, safer, few parts buried, etc. However, many accidentshappened due to the buckling of arms of the radial gates. Actually, the defects of traditionaldesign methods are the major reason for the accidents. In traditional design methods, a gate isinitially designed according to engineers’ experiences and the old specification issued nearlytwo decades ago. Especially, in recent years the rapid development on the computationaltheories and computer technology stimulates the more reasonable and even innovativedesigns of radial gates. However, the works paid close attention to the size optimization andsafety check of SRGs. Generally, the gate, a spatial structure, has to be simplified too much indesign process. Although the safety coefficients are much bigger (than the gate needs), thestress distribution are not uniform which threats the safety of gate. Therefore, the designmethod for radial gates needs improved.Structural Optimization theory is one of the effective methods to give a better design ofa radial gate. Till now, most of research work on radial gates is focused on its safety checkand shape optimization. One can find few research of radial gate design according tocontinuum topology optimization theory.In the present method, an investigation on the new design method for radial gates iscarried out according the continuum topology optimization and finite element software.Especially an oblique armed radial gate running in real project is redesigned by the presentmethod. Considering the difference between the span and depth of the gate, two types ofdesign procedures are given. The major steps in the current design method are expressed indetail, e.g.,First, the oblique armed radial gate is considered being composed with such maincomponents as arms, water retaining face plate and its supporting frame;Second, the optimal topologies of the arms and supporting frame are obtained bytopology optimization method;Third, the new radial gate is assembled using the components obtained above;Fourth, size optimization for the new gate is performed with consideration of theconstraints on structural stiffness, strength and stability; Final, the safety check of the new gate is fulfilled under other loading conditions.By comparing with the traditional design of the gate, the new gate is around24%lighterand the natural frequency of structure is3.5Hz which is far away from the frequency intervalof [03]Hz excited by water flow. Lighter structure means manufacturing cost on manufactureis reduced and the gate is easier to assemble and operate. Higher natural frequency impliesthe dynamic stability of gate is improved under water flow loading conditions.