摘要：经典克拉尼图形(Chladni patterns,CP)是特征向量的视觉表示,在振动分析、乐器设计、粒子操纵和分离等领域中具有广泛的应用.均质结构通常会表现出高度规则化的CP,这限制它们的应用场景.因此,实现面向应用来逆向设计结构的CP是非常重要的,而这可以通过使用拓扑优化来实现CP的逆向设计.本研究提出了一种使用基于密度的拓扑优化算法来设计结构CP的方法.优化列式中,给出了描述图形的指标函数,并以最小化特征向量和目标CP之间的误差构建了优化目标.数值结果表明,所提出的方法可以为指定的单阶或多阶CP生成新颖的材料分布.这表明了本文所提出的方法能够实现CP的精确定制设计,进一步为面向应用的需求提供了更多选择.

摘要：Experimental study was carried out on the in-plane bending behavior of glass plates without lateral supports, and the effects of the factors, such as height-to-span ratio, on the stability of glass panels were studied. Results show that the in-plane bending glass plates with both ends simply supported and their upper edge free lose overall stability under loads, which belongs to the limit-point type of instability. It is found that the buckling load increases linearly with the increase of height-to-span ratio of the glass plates. The lateral stress of in-plane bending glass plates without lateral supports increases linearly under loads; while the large-area stress increases nonlinearly and the lateral stress is not the controlling factor of instability. In finite element analysis, the first buckling mode is regarded as the initial imperfection and imposed on the model as 1/1000 of the span of the components. The numerical buckling load according to the theory of large deflection is less than the experiment result, which is more conservative and can provide some reference for design. For the design method, when the in-plane load is imposed on the glass plate, its lateral strength and the deflection should be verified. Considering the stability of the in-plane bending glass plate without reliable lateral support, buckling is another possible failure mode and calls for verification.

摘要：The response surface method(RSM) is one of the main approaches for analyzing reliability problems with implicit performance *** improved adaptive RSM based on uniform design(UD) and double weighted regression(DWR) was *** the proposed method,the basic principle of the iteratively adaptive response surface method is *** design is used to sample the fitting *** a double weighted regression system considering the distances from the fitting points to the limit state surface and to the estimated design points is set to determine the coefficients of the response surface *** with the conventional approaches,the fitting points selected by UD are more representative,and a better approximation in the key region is also observed with *** examples show that the proposed method has good convergent capability and computational accuracy.

摘要：Remodeled clay and sand rock specimens were prepared by designing lateral confinement and water drainage experiments based on the stress exerted on granular materials in a waste *** in situ test was conducted in an internal waste dump;the physical and mechanical parameters of the remodeled rock mass dumped at different time and depths were *** on statistics,regression analysis was performed with regard to the shearing stress parameters acquired from the two *** factors,such as remodeling pressure(burial depth),remodeling time(amount of time since waste was dumped),and the corresponding functional relationship,were *** indicates that the cohesion of the remodeled clay and its remodeling pressure are correlated by a quadratic function but are not correlated with remodeling time *** situ experimental results indicate that the shear strength of reshaped granular materials in the internal dump is positively correlated with burial depth but poorly correlated with time *** Cand burial depth H follow a quadratic function,specifically for a short time since waste has been *** revealed by both in situ and laboratory experiments,the remodeling strength of granular materials varies in a certain *** consistency of such materials verifies the reliability of the remodeling experimental program.

摘要：The state of the art of the study on the hydraulic conductivity of GCLs is presented in terms of the influence of the effective stress,chemical interactions,freeze-thaw cycles and temperature *** changes of void ratio caused by changes of effective stress have a direct linear effect on the hydraulic conductivity,regardless of the cation concentration or the thickness of the adsorbed *** hydraulic conductivity is related to the relative abundance of monovalent and divalent cation(RMD),and RMD has a great effect on the hydraulic conductivity in weak *** long-term susceptibility of GCLs to increased hydraulic conductivity as a response to repeated freeze-thaw cycling is minimal,which has been proved after 150 freeze-thaw *** potential of desiccation cracking increases with the increasing temperature gradient and is related to the initial subsoil water content,the applied overburden stress,etc.

摘要：折板因为结构简单而被广泛加工成吸能构件.输入动能恒定时,不同材料的折板在不同的动力学条件下。最终变形有明显的差异.为了更好地解释这种现象,利用Maple软件对Zhang-Yu吸能器方程编写了通用程序,并首次求得了吸能器的广义坐标(转角9)随时间的变化规律.为了更好地了解吸能器的运动受参数变化的影响,计算了吸能器动力学的相图经过大量数值模拟,我们发现四折板吸能器应当是"质量敏感"型吸能结构.同时,本文建立了低碳钢和6061-T6铝合金两类折板的动态屈曲的有限元模型,并与Caladine-English动态实验和Zhang-Yu刚黏塑性模型进行了比较.结果表明.(1)Zhang-Yu刚黏塑性模型对低碳钢这种应变本敏感型材料更具有指导意义,而折板为6061-T6铝合金这种应变率不敏感材料时误差更大.并且随着初始折角的增大.Zhang-Yu刚黏塑性模型的预测误差进一步扩大.(2)根据有限元模型修正塑性铰的等效塑性长度λ值,可以提高Zhang-Yu刚黏塑性模型的预测伯的精度,我们的研究结果对折板吸能结构的设计与制造有一定的指导意义.

摘要：engineering designs for mountainous highways emphasize compliance checking to ensure safety. However, relying solely on compliance checking may lead designers to minimize costs at the expense of high risk indicators, since the overall risk level of the highway design is unknown to the designers. This paper describes a method for the simultaneous consideration of traffic safety risks and the associated cost burden related to the appropriate planning and design of a mountainous highway. The method can be carried out in four steps: First, the highway design is represented by a new parametric framework to extract the key design variables that affect not only the life-cycle cost but also the operational safety. Second, the relationship between the life-cycle cost and the operational safety risk factors is established in the cost-estimation functions. Third, a fault tree analysis (FTA) is introduced to identify the traffic risk factors from the design variables. The safety performance of the design solutions is also assessed by the generalized linear-regression model. Fourth, a theory of acceptable risk analysis is introduced to the traffic safety assessment, and a computing algorithm is proposed to solve for a cost-efficient optimal solution within the range of acceptable risk, in order to help decision-makers. This approach was applied and examined in the Sichuan–Tibet Highway engineering project, which is located in a complex area with a large elevation gradient and a wide range of mountains. The experimental results show that the proposed approach significantly improved both the safety and cost performance of the project in the study area.

摘要：Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology and engineering condition of Qishan Coal Mine in Xuzhou, the failure characteristics of pump chambers at the –1000 m level show that the main cause can be attributed to the spatial effect induced by intersectional chambers, where one pump is constructed per well. We developed an opti-mized design of the pump room, in which the pump wells in the traditional design are integrated into one compounding well. We suggest that the new design can limit the spatial effect of intersectional chambers during construction given our relevant numerical simulation. The new design is able to simplify the structure of the pump chamber and reduce the amount of excavation required. Based on a bolt-mesh-anchor with a rigid gap coupling supporting technology, the stability of pump chamber can be improved greatly.

摘要：The three-dimensional (3D) deformation effect of the slope engineering underthe step-by-step excavation for the Antaibao surface mine was analyzed using the FLAG^3Dtechnique. An optimal excavated scheme with a relatively steeper slope angle of 47^(。) instead of 30^(。) was successfully implemented at the west wall in the geological section73200 of the mine area, where the 3D effect of the nonlinear large deformation of theslope was taken into account. Based on the above research conclusion, put forward thecountermeasures of shortening mining length, excavating by different regions, timely footbackfilling to protect the excavated slope, and monitoring and feedback adjustment bystudying the nonlinear effect. The results show that these countermeasures are effective incontrolling maximum deformation and increasing the stability of the slope.

摘要：Based on some assumptions,the dynamic governing equation of anchorage system is *** calculation formula of natural frequency and the corresponding vibration mode are ***,the feasibility of the theoretical method is verified by using a specific example combined with other *** is found that the low-order natural frequency corresponds to the first mode of vibration,and the high-order natural frequency corresponds to the second mode of vibration,while the third mode happens only when the physical and mechanical parameters of anchorage system meet certain *** the increasing of the order of natural frequency,the influence on the dynamic mechanical response of anchorage system decreases ***,a calculating method,which can find the dangerous area of anchorage engineering in different construction sites and avoid the unreasonable design of anchor that may cause resonance,is proposed to meet the seismic precautionary *** method is verified to be feasible and effective by being applied to an actual *** study of basic dynamic features of anchorage system can provide a theoretical guidance for anchor seismic design and fast evaluation of anchor design scheme.