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Carbon fiber-reinforced composites are widely used in the aerospace industry due to their exceptional mechanical properties. However, the dome region of composite pressure vessels is prone to stress concentrations under internal pressure, often resulting in premature failure and reduced burst strength. This study developed a finite element model of a reinforced dome structure, which showed excellent agreement with hydrostatic test results, with less than 5.9% deviation in strain measurements. To optimize key reinforcement parameters, a high-accuracy surrogate model based on a backpropagation neural network was integrated with a multi-objective genetic algorithm. The results indicate that compared to the unreinforced dome, the optimized structure reduced the maximum fiber-aligned stress in the dome region by 6.8%; moreover, it achieved a 9.3% reduction in overall mass compared to the unoptimized reinforced configuration. These findings contribute to the structural optimization of composite pressure vessel domes.

Pipeline transport is one of the most capital and metal-intensive types of transport. Being environmentally friendly during normal operation, it can cause irreparable damage to nature in case of accidents. Therefore, the issues of reliability and efficiency of operation of field and main oil and gas pipelines and control of energy characteristics during their operation are of no small importance. The amount of additional pressure in the system from hydrodynamic shocks is determined by the density and elasticity of the pumped liquid, as well as the elasticity of the walls of the pipeline itself. The article considers the problem of estimating the critical speed and dynamic loads during the movement of multiphase flows through pipelines, taking into account the interaction of the phases. Dynamic loads are calculated based on the change in critical speed for various structural forms formed as a result of the interaction of phases. These loads, compared to shell structures with separated phases, turned out to be less than when moving in a mold with dispersed bubble structures. The characteristics of the critical speed distribution are determined. It has been determined that the dynamic loads arising in multiphase flows with a predominance of the gas phase are many times higher than in systems where the liquid phase is the leading medium, and the dependence of the pressure distribution on the densities of the phases has been shown. The work analyzes various modes of hydraulic shock. The volume of oil caused by its compression during hydraulic shock was calculated. The results of calculating the increase in the volume of an oil pipeline due to a dynamic impact are presented.

Steel dome structures, with their striking structural forms, take a place among the impressive and aesthetic load bearing systems featuring large internal spaces without internal columns. In this paper, the seismic design optimization of spatial steel dome structures is achieved through three recent metaheuristic algorithms that are water strider (WS), grey wolf (GW), and brain storm optimization (BSO). The structural elements of the domes are treated as design variables collected in member groups. The structural stress and stability limitations are enforced by ASD-AISC provisions. Also, the displacement restrictions are considered in design procedure. The metaheuristic algorithms are encoded in MATLAB interacting with SAP2000 for gathering structural reactions through open application programming interface (OAPI). The optimum spatial steel dome designs achieved by proposed WS, GW, and BSO algorithms are compared with respect to solution accuracy, convergence rates, and reliability, utilizing three real-size design examples for considering both the previously reported optimum design results obtained by classical metaheuristic algorithms and a gradient descent-based hyperband optimization (HBO) algorithm.

Reinforced concrete shell structures produced using an inflated form are widely used in large‐span thin‐shell spatial structures. Unlike the construction technology of traditional concrete building structures, this method involves prefabricating the membrane material into a designed shape as the construction framework. After inflation, a polyurethane layer is sprayed, steel bars are placed, and concrete is sprayed inside the inflatable membrane. This innovative construction method effectively addresses the issues of complex framework procedures, high costs, and difficulty in concrete pouring in traditional thin concrete shell construction, offering significant advantages. However, despite its wide application in the industrial sector and the gradual maturation of related construction techniques, the structure still faces many technical challenges that need to be addressed. Existing research remains insufficient in areas such as standardization processes, material performance optimization, and long‐term durability, which limit the further development and application of this technology. Although there have been some related reviews, most of them have not comprehensively covered all the key technologies in this field. This article provides the first systematic review, filling the research gap in the existing literature. By reviewing the relevant background, structural forms, engineering applications, and key technologies of reinforced concrete shell structures produced using an inflated form, this article proposes several improvements for these technical challenges and discusses future research directions, particularly in the areas of standardization processes, material performance optimization, and long‐term durability.

Among the many clean heating technologies with solar energy as the main energy source, a water pit for solar seasonal heat storage and heating technology has been actively promoted by many countries due to its reliable technology and mature engineering applications. The insulated top cover is the most important, critical, and expensive component of the water pit for solar heat storage. In this paper, the structural design, material application, and evaluation methods of an insulated top cover were reviewed based on scientific references and practical projects. First, the whole type and split type structure forms of the insulated top cover were summarized, and the applicable scenes of different structural forms were pointed out. Second, the performance analysis of impermeable materials and insulation materials of the insulated top cover was carried out, and the performance characteristics of the corresponding materials as well as the problems to be solved were pointed out. Finally, the performance evaluation method of the insulated top cover was comprehensively analyzed, and it was pointed out that there is still a lack of scientific and efficient evaluation parameters and monitoring methods for an insulated top cover in line with engineering practice. The purpose of this paper was to provide reference for the scientific research and engineering application of a water pit for solar seasonal heat storage and heating technology.

This paper re-considers a recent analysis on the so-called Couplet–Heyman problem of least-thickness circular masonry arch structural form optimization and provides complementary and novel information and perspectives, specifically in terms of the optimization problem, and its implications in the general understanding of the Mechanics (statics) of masonry arches. First, typical underlying solutions are independently re-derived, by a static upper/lower horizontal thrust and a kinematic work balance, stationary approaches, based on a complete analytical treatment; then, illustrated and commented. Subsequently, a separate numerical validation treatment is developed, by the deployment of an original recursive solution strategy, the adoption of a discontinuous deformation analysis simulation tool and the operation of a new self-implemented Complementarity Problem/Mathematical Programming formulation, with a full matching of the achieved results, on all the arch characteristics in the critical condition of minimum thickness.

Shape sensing as a crucial component of structural health monitoring plays a vital role in real-time actuation and control of smart structures, and monitoring of structural integrity. As a model-based method, the inverse finite element method (iFEM) has been proved to be a valuable shape sensing tool that is suitable for complex structures. In this paper, we propose a novel approach for the shape sensing of thin shell structures with iFEM. Considering the structural form and stress characteristics of thin-walled structure, the error function consists of membrane and bending section strains only which is consistent with the Kirchhoff–Love shell theory. For numerical implementation, a new four-node quadrilateral inverse-shell element, iDKQ4, is developed by utilizing the kinematics of the classical shell theory. This new element includes hierarchical drilling rotation degrees-of-freedom (DOF) which enhance applicability to complex structures. Firstly, the reconstruction performance is examined numerically using a cantilever plate model. Following the validation cases, the applicability of the iDKQ4 element to more complex structures is demonstrated by the analysis of a thin wallpanel. Finally, the deformation of a typical aerospace thin-wall structure (the composite tank) is reconstructed with sparse strain data with the help of iDKQ4 element.

This research is taking the first steps toward applying a 2D dragonfly wing skeleton in the design of an airplane wing using artificial intelligence. The work relates the 2D morphology of the structural network of dragonfly veins to a secondary graph that is topologically dual and geometrically perpendicular to the initial network. This secondary network is referred as the reciprocal diagram proposed by Maxwell that can represent the static equilibrium of forces in the initial graph. Surprisingly, the secondary graph shows a direct relationship between the thickness of the structural members of a dragonfly wing and their in‐plane static equilibrium of forces that gives the location of the primary and secondary veins in the network. The initial and the reciprocal graph of the wing are used to train an integrated and comprehensive machine‐learning model that can generate similar graphs with both primary and secondary veins for a given boundary geometry. The result shows that the proposed algorithm can generate similar vein networks for an arbitrary boundary geometry with no prior topological information or the primary veins' location. The structural performance of the dragonfly wing in nature also motivated the authors to test this research's real‐world application for designing the cellular structures for the core of airplane wings as cantilever porous beams. The boundary geometry of various airplane wings is used as an input for the design proccedure. The internal structure is generated using the training model of the dragonfly veins and their reciprocal graphs. One application of this method is experimentally and numerically examined for designing the cellular core, 3D printed by fused deposition modeling, of the airfoil wing; the results suggest up to 25% improvements in the out‐of‐plane stiffness. The findings demonstrate that the proposed machine‐learning‐assisted approach can facilitate the generation of multiscale architectural patterns inspired by nature to form lightweight load‐bearable elements with superior structural properties. This research investigates the use of graphic statics and machine learning to analyze the structural geometry of a dragonfly wing, understand its performance, and generate similar patterns. It can be used in a more universal workflow to generate structural forms inspired from the collected dataset of a wider range of species.

The gas phase flow field inside a cyclone separator is crucial to the particle separation process. Previous studies have paid attention to the steady-state characteristics of the gas phase flow field, while research on its dynamic characteristics remains insufficient. Meanwhile, cyclone separators often adopt different structural forms according to the process requirements, the evolution laws of the dynamic characteristics flow field within them are still not well understood. Therefore, in this study, a hot-wire anemometer (HWA) was employed to measure the instantaneous tangential velocity of the gas phase flow fields within different structural cyclone separators (cylinder type, cylinder–cone (no hopper), and cylinder–cone (with hopper)). Comparative analyses and discussions were conducted regarding the dynamic characteristic distribution rules of the flow field in the time domain and the frequency domain. The results revealed that the dimensionless tangential velocity distributions of different types of cyclone separators all conformed to the Rankine vortex structure. The instantaneous tangential velocity fluctuated with low frequency and high amplitude, and the low-frequency velocity fluctuation exhibited a transfer behavior along the radial direction. Compared with the cylinder–cone-type cyclone separator, the tangential velocity in the cylinder-type cyclone separator fluctuated more greatly, and its quasi-periodic behavior was also more obvious. The time-averaged tangential velocity, the tangential velocity fluctuation intensity (Sd), and the dominant fluctuation frequency all had obvious attenuation along the axial direction in the cylinder-type cyclone separator, while the above-mentioned parameters had no attenuation along the axial direction in cylinder–cone-type cyclone separators. Additionally, the backflow from the hopper of the cylinder–cone-type cyclone separator (with hopper) led to an increase in the instantaneous tangential velocity fluctuation intensity of the local flow field near the dust outlet, as well as the occurrence of the “double dominant frequencies” phenomenon.

This work seeks to define original ways of creating architectonic forms using kinesiology studies. A series of methodologies are devised to record subjects in motion, with analogue and digital modelling techniques rigorously used independently and in combination to transpose these into sculptural figures with differing levels of formal fidelity and dimensional precision. Surface structures, and in particular thin shells, are found to have great potential for moving from abstract figures to structural forms. Such structures are traditionally problematic in terms of ‘constructional energy’, which has limited their usefulness and application. In response, the ‘hanging cloth reversed’ modelling technique devised by Heinz Isler is investigated to capitalise on the ambiguity between large-scale models and small structures. A construction method is devised that accords with the principles of structural art which, significantly, suggests that (small-span) shell structures could be liberated from the strictures of formwork to create economic, efficient and elegant minimal structures.