摘要：With the fast development of computational mechanics and the capacity as well as the speed of modern computers,simulation-based structural optimization has become an indispensable tool in the design process of competitive *** paper presents a brief description of the current status of structural optimization by reviewing some significant progress made in the last *** research topics are also *** entire literatures of the field are not covered due to the limitation of the length of *** scope of this review is limited and closely related to the authors＇ own research interests.

摘要：Severe stress concentration occurs around circular vent holes of an industrial turbine sealing *** paper investigates the structural design and optimization for the vent holes to effectively reduce the maximum von Mises stress and improve the fatigue life of the turbine sealing *** efficient integrated design optimization method is presented based on a novel non-circular vent hole design method in combination with a variable dimension sub-model method,a self-developed modeling and meshing tool,and the Multi-Island Genetic *** proposed non-circular vent hole is biaxial symmetric and consists of four smoothly connected *** variable dimension sub-model method is utilized to obtain accurate results in the fields around the vent holes within the computationally acceptable *** modeling and meshing tool is developed by using the Tcl/Tk Scripts to rebuild the geometry and generate the high-quality hexahedral mesh *** Multi-Island Genetic Algorithm is adopted to solve the studied constrained optimization *** optimization,the maximum von Mises stress is reduced from 1305.644 MPa to 963.435 MPa,and the fatigue life is increased from 3091 cycles to 30,297 *** results show that the proposed design and optimization methods can significantly improve the performance of the turbine sealing disk along with the remarkable drop in stress concentration.

摘要：The present study investigates computer-antomated design and structural optimization of concrete slab frame bridges considering investment cost based on a complete 3D model. Thus, a computer code with several modules has been developed to produce parametric models of slab frame bridges. Design loads and load combinations are based on the Eurocode design standard and the Swedish design standard for bridges. The necessary reinforcement diagrams to satisfy the ultimate and serviceability limit states, including fatigue checks for the whole bridge, are calculated according to the aforementioned standards. optimization techniques based on the genetic algorithm and the pattern search method are applied. A case study is presented to highlight the efficiency of the applied optimization algorithms. This methodology has been applied in the design process for the time-effective, material-efficient, and optimal design of concrete slab frame bridges.

摘要：Although the genetic algorithm (GA) has very powerful robustness and fitness, it needs a large size of population and a large number of iterations to reach the optimum result. Especially when GA is used in complex structural optimization problems, if the structural reanalysis technique is not adopted, the more the number of finite element analysis (FEA) is, the more the consuming time is. In the conventional structural optimization the number of FEA can be reduced by the structural reanalysis technique based on the approximation techniques and sensitivity analysis. With these techniques, this paper provides a new approximation model-segment approximation model, adopted for the GA application. This segment approximation model can decrease the number of FEA and increase the convergence rate of GA. So it can apparently decrease the computation time of GA. Two examples demonstrate the availability of the new segment approximation model.

摘要：It is known that structural optimization may lead to designs of structures having low stability and sometimes even kinematically unstable designs. This paper presents a robust design method for improving the stability of opti mized structures. A new approach is proposed, in which cer tain perturbation loads are introduced and the corresponding compliance is added to the objective function as a penaliza tion. The stability of the optimized structures can thus be improved substantially by considering structural responses to the original and the introduced loads. Numerical exam ples show the simplicity and effectiveness of the proposed method.

摘要：Three degrees of freedom （3-DOF） Helmholtz resonator which consists of three cylindrical necks and cavities connected in series （neck-cavity-neck-cavity-neck-cavity） is suitable to reduce flow pulsation in hydraulic system. A novel lumped parameter model （LPM） of 3-DOF Helmholtz resonator in hydraulic system is developed which considers the viscous friction loss of hy- draulic fluid in the necks. Applying the Newton＇s second law of motion to the equivalent mechanical model of the resonator, closed-form expression of transmission loss and resonance frequency is presented. Based on the LPM, an optimal design method which employs rotate vector optimization method （RVOM） is proposed. The purpose of the optimal design is to search the reso- nator＇s unknown parameters so that its resonance frequencies can coincide with the pump-induced flow pulsation harmonics respectively. The optimal design method is realized to design 3-DOF Helmholtz resonator for a certain type of aviation piston pump hydraulic system. The optimization result shows the feasibility of this method, and the simulation under optimum parame- ters reveals that the LPM can get the same precision as transfer matrix method （TMM）.

摘要：A surrogate based particle swarm optimization （SBPSO） algorithm which combines the surrogate modeling technique and particle swarm optimization is applied to the reliability- based robust design （RBRD） of composite pressure vessels. The algorithm and efficiency of SBPSO are displayed through numerical examples. A model for filament-wound composite pressure vessels with metallic liner is then studied by netting analysis and its responses are analyzed by using Finite element method （performed by software ANSYS）. An optimization problem for maximizing the performance factor is formulated by choosing the winding orientation of the helical plies in the cylindrical portion, the thickness of metal liner and the drop off region size as the design variables. Strength constraints for composite layers and the metal liner are constructed by using Tsai-Wu failure criterion and Mises failure criterion respectively. Numerical examples show that the method proposed can effectively solve the RBRD problem, and the optimal results of the proposed model can satisfy certain reliability requirement and have the robustness to the fluctuation of design variables.

摘要：Soft machines are combinations of hard and soft active materials, thus the coupling and interaction between soft and hard components dictate the performance of soft machines. structural optimization has been intensively used for design of conventional hard machines, while, to our best knowledge, few attempts have been made towards optimal design of soft machines. Here, we describe the sizing optimization problem of a dielectric elastomer(DE) actuated mechanical amplifier, and achieve the optimal design through combination of a commercial finite element method(FEM) software and an optimization automation *** then design, fabricate and demonstrate a locomotive soft machine driven by DE actuator with amplified displacement *** methodology and results present here open the door towards optimal designs of active materials based soft machines.

摘要：Based on a multiobjective approach whose objective function (OF) vector collects stochastic reliability performance and structural cost indices, a structural optimization criterion for mechanical systems subject to random vibrations is presented for supporting engineer’s design. This criterion differs from the most commonly used conventional optimum design criterion for random vibrating structure, which is based on minimizing displacement or acceleration variance of main structure responses, without considering explicitly required performances against failure. The proposed criterion can properly take into account the design-reliability required performances, and it becomes a more efficient support for structural engineering decision making. The multiobjective optimum (MOO) design of a tuned mass damper (TMD) has been developed in a typical seismic design problem, to control structural vibration induced on a multi-storey building structure excited by nonstationary base acceleration random process. A numerical example for a three-storey building is developed and a sensitivity analysis is carried out. The results are shown in a useful manner for TMD design decision support.

摘要：The Blended-Wing-Body(BWB) is an unconventional configuration of aircraft and considered as a potential configuration for future commercial aircraft. One of the difficulties in conceptual design of a BWB aircraft is structural mass prediction due to its unique structural feature. This paper presents a structural mass prediction method for conceptual design of BWB aircraft using a structure analysis and optimization method combined with empirical calibrations. The total BWB structural mass is divided into the ideal load-carrying structural mass, non-ideal mass, and secondary structural mass. structural finite element analysis and optimization are used to predict the ideal primary structural mass, while the non-ideal mass and secondary structural mass are estimated by empirical methods. A BWB commercial aircraft is used to demonstrate the procedure of the BWB structural mass prediction method. The predicted mass of structural components of the BWB aircraft is presented, and the ratios of the structural component mass to the Maximum TakeOff Mass(MTOM) are discussed. It is found that the ratio of the fuselage mass to the MTOM for the BWB aircraft is much higher than that for a conventional commercial aircraft, and the ratio of the wing mass to the MTOM for the BWB aircraft is slightly lower than that for a conventional aircraft.