Thin-Walled Structures最新文献

{"title":"Multi-duration robust topology optimization of fiber-reinforced composite structures under dynamic loading","authors":"Jianshu Wang ,&nbsp;Shouzheng Sun ,&nbsp;Xudong Ran ,&nbsp;Tianrong Huang ,&nbsp;Hongya Fu ,&nbsp;Zhenyu Han ,&nbsp;Shuhai Huang ,&nbsp;Peng Zhang","doi":"10.1016/j.tws.2026.114706","DOIUrl":"10.1016/j.tws.2026.114706","url":null,"abstract":"<div><div>In complex engineering environments, the duration of dynamic loads experienced by structures is highly variable. Traditional topology optimization approaches typically address only a single load duration, posing substantial safety risks. This study proposed a multi-duration robust topology optimization method for the design of fiber-reinforced composite structures (FRCS) subjected to dynamic loads with multiple potential durations. Operating under the assumption of linear elastic dynamics, the method employed time-averaged displacement fields to guide fiber orientation updates, effectively addressing the time-varying characteristics of principal stress directions during dynamic responses. To capture the morphological variability of structures under different load durations, a novel metric called the Morphological Dispersion Index (MDI) was introduced. Guided by the MDI, representative sub-durations were selected, and robust topology optimization was achieved by aggregating the objective functions and sensitivities of each sub-duration throughout the optimization process. Experimental validation of the numerical simulation framework was conducted using 3D printing and Digital Image Correlation (DIC). Benchmark cases demonstrated that variations in load duration significantly influenced the optimization outcomes. Compared to designs optimized for a single load duration, the proposed method reduced structural elastic strain energy by 29.98% to 75.80%, while maintaining stable and efficient structural configurations. The method exhibited strong adaptability across varying load durations, offering a new perspective for the robust design of FRCS under dynamic loading conditions.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114706"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Level-set topology optimization of electrode-patterned piezoelectric metasurfaces for far-field ultrasonic focusing via the Kirchhoff–Helmholtz integral method","authors":"Sang Uk Park ,&nbsp;Jaeyub Hyun","doi":"10.1016/j.tws.2026.114720","DOIUrl":"10.1016/j.tws.2026.114720","url":null,"abstract":"<div><div>Conventional focusing methods using acoustic lenses have limitations, such as low transmittance and mechanical crosstalk, which degrade the on-demand focusing performance. This study presents a level-set topology optimization framework for designing electrode patterns on a planar piezoelectric metasurface. In the proposed framework, the electrode topologies are implicitly represented by a signed-distance function and evolved through the Hamilton-Jacobi equation using boundary point sensitivities calculated by the adjoint variable method. A parameterization scheme for the electric potential boundary condition is devised to parameterize the electrode patterns through topological design variables, i.e., area fractions of design elements cut by the zero level-set contour. The far-field acoustic pressure is efficiently evaluated using the Kirchhoff-Helmholtz integral method, leading to significant computational cost savings during optimization. Numerical investigations demonstrate that the proposed framework achieves well-defined focusing in both on- and off-axis configurations, which supports its use as a lens-free approach for far-field ultrasonic focusing.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114720"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vibration reduction and wave reflection performance of radial-periodic annular acoustic black hole plate","authors":"Yue Bao ,&nbsp;Linxin Cai ,&nbsp;Chenliang Zheng ,&nbsp;Shaogan Ye ,&nbsp;Xiaosong Xia ,&nbsp;Liang Hou ,&nbsp;Xiaoran Wang","doi":"10.1016/j.tws.2026.114679","DOIUrl":"10.1016/j.tws.2026.114679","url":null,"abstract":"<div><div>Periodic two-dimensional acoustic black hole (ABH) plates have attracted considerable attention due to their lightweight and high-efficiency vibration control capabilities. However, most existing studies focus on translationally periodic structures, whereas the vibration analysis of circular ABH plates with radially periodic and enlarged tapered-thickness regions remains intractable because of the quasi-periodic characteristics and complex wave interactions. In this study, a radially periodic annular ABH plate model is proposed, and its dynamic performance is systematically compared with that of a conventional single ABH circular plate. To evaluate the dynamic behavior of the proposed configuration, a transfer matrix method based on the partitioned-element concept is developed and validated through finite element simulations. In addition, the energy dissipation of flexural wave is characterized using a wave-based approach. Analyses of wave reflection coefficients and vibration responses demonstrate that the radially periodic ABH circular plate exhibits pronounced advantages in damping coupling and broadband vibration attenuation, which can be attributed to a significant increase in localized ABH modes and the enhanced global-damping modes. The results show that both the mean velocity of the uniform portion and the vibration transmission loss are reduced by &gt;20 dB compared with the conventional circular ABH plate over the frequency range of 10–6000 Hz. Dynamic experiments further confirm the accuracy of the theoretical predictions, as well as the effectiveness of the proposed structure in vibration attenuation and isolation. Moreover, comprehensive parametric analyses reveal that reducing the residual thickness and increasing the power-law exponent can significantly enhance the vibration attenuation performance of radially periodic ABH structures. This work provides new insights into broadband vibration absorption and isolation in circular plate structures.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114679"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bond durability and deterioration mechanism of NiTi SMA-to-steel interface in simulated pipeline sediment","authors":"Jun Deng ,&nbsp;Min-Ting Zhong ,&nbsp;Jun-Bo Liang ,&nbsp;Zong-Chao Liu ,&nbsp;Bo Guo ,&nbsp;Hui-Qiang Li ,&nbsp;Dong Guo","doi":"10.1016/j.tws.2026.114683","DOIUrl":"10.1016/j.tws.2026.114683","url":null,"abstract":"<div><div>This study investigated the feasibility of using nickel-titanium shape memory alloy (NiTi SMA) to strengthen steel pipelines by evaluating the long-term bond performance under oil and gas pipeline sediment conditions. Four groups of single-lap shear NiTi SMA-to-steel joints were fabricated using optimized surface preparation protocols, with three replicates per group. The joints were then immersed in a synthetic pipeline sediment solution for periods of 30, 60, and 90 days to simulate actual operational conditions. Following immersion, lap-shear tests were conducted to assess the bond performance variations. Bond strength increased from 0 to days, likely due to continued curing of the adhesive, but decreased thereafter because of corrosion. Additionally, interfacial shear stress distributions and bond-slip behaviors were derived from the measured strain profiles along the NiTi SMA, accounting for its nonlinear stress-strain response. Furthermore, SEM, EDS, FTIR, and XPS analyses were performed to investigate the microscopic morphology and chemical structure variations of the bonding interface. These analyses revealed that bond deterioration was attributed to the hydrolytic cleavage, radical-induced crosslinking, and ingress of corrosive ions.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114683"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical solutions of functionally graded microbeam models based on the modified couple stress theory: A comparative study of Euler-Bernoulli, Timoshenko and Reddy beams","authors":"Shenao Zhao ,&nbsp;Lei Li ,&nbsp;Pengpeng Shi","doi":"10.1016/j.tws.2026.114648","DOIUrl":"10.1016/j.tws.2026.114648","url":null,"abstract":"<div><div>Mechanical analysis of micro-scale beam structures is critical for accurate displacement prediction. This study proposes an analytical framework based on the modified couple stress theory (MCST) to investigate the size-dependent static bending behavior of functionally graded (FG) Reddy microbeam. A material length scale parameter is introduced to capture size effects, while the material properties are assumed to vary continuously along the thickness direction. Within this framework, the Euler–Bernoulli, Timoshenko, and Reddy beam models are systematically integrated, thereby revealing their intrinsic relationships and degeneration paths at the micro-scale, along with the additional contributions of higher-order beam models. The results show that the linear contribution has a positive correlation with transverse displacement, while both quadratic and hyperbolic contributions exhibit negative correlations. Analytical solutions are derived for simply supported, cantilever, and clamped boundary conditions. A simply supported beam is used as an example to demonstrate that the proposed FG Reddy microbeam solution ultimately reduces to the classical Euler-Bernoulli beam solution. The accuracy of the present analytical solution is verified by comparing it with results reported in previous works. A detailed analysis is conducted to examine the effects of the gradient index, material length scale parameter, geometric configuration, and boundary conditions on the bending deformation and internal force distributions of microbeams. This study provides valuable insights into the mechanical behavior of different beam models at the micro-scale.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114648"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact attenuation of a novel highway crash cushion using a kirigami corrugated honeycomb core","authors":"Wen Zhao ,&nbsp;Zhejian Li ,&nbsp;Hong Hao ,&nbsp;Wensu Chen","doi":"10.1016/j.tws.2026.114703","DOIUrl":"10.1016/j.tws.2026.114703","url":null,"abstract":"<div><div>Redirective crash cushions are widely used in highway safety protection systems as impact attenuation devices. This study presents a novel redirective crash cushion that utilizes the Kirigami corrugated honeycomb (KC) structure as its primary energy absorbing (EA) module. A full-scale KC EA module was tested using a rigid car impact system to observe its performance and validate the finite element model. Using the validated model, a detailed numerical model of a vehicle and the novel crash cushion were developed. Based on the Chinese standard JTG B05–01–2013, vehicle impacts under different scenarios onto the crash cushion were simulated under the TA level (80 km/h) impact conditions to evaluate compliance in terms of the impact attenuation and redirection performance. A comparative analysis was also conducted against the existing arc-type crash cushion, focusing on three key aspects: occupant injury risk, post-impact vehicle kinematics, and cushion performance. Five indicators, including the vehicle’s acceleration and deformation, the vehicle exit angle, energy absorption, and overall deformation of the crash cushion, were considered to evaluate the performance. Furthermore, under TS level (100 km/h) impact conditions, a graded configuration of the KC modules with the same mass was introduced to enhance energy absorption. The results showed compliance of the proposed KC crash cushion with all requirements under various impact scenarios and improved performance as compared to the existing arc-type crash cushion. In frontal impacts, it reduced vehicle acceleration and reduced vehicle front deformation by 20 %, decreasing the occupant injury risk by 13 %. In 15-degree oblique impacts, it reduced the vehicle exit angle by 13°, thereby lowering the risk of secondary collisions. Additionally, the graded configuration improved the energy absorption capacity by 19 % and effectively controlled peak vehicle acceleration, further enhancing protective performance and demonstrating strong tunability. Overall, the KC crash cushion provides a lightweight, economical, and reliable solution for highway safety protection, representing a significant advancement in vehicle collision mitigation technology.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114703"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Semi-analytical solutions for lateral-torsional buckling of steel I-beams under localized fire","authors":"Longkai Chen,&nbsp;Chao Zhang","doi":"10.1016/j.tws.2026.114693","DOIUrl":"10.1016/j.tws.2026.114693","url":null,"abstract":"<div><div>In certain fire scenarios, such as localized fires, steel beams may experience thermal gradients in both longitudinal and transverse directions. These gradients degrade the steel’s mechanical properties and induce thermal expansion, generating complex internal forces in beams with restrained ends. Such thermal actions strongly influence the lateral-torsional buckling behavior of beams under transverse distributed load. Hitherto, research studies of the lateral-torsional buckling of steel beams under localized fires remain scarce. To address this gap, this study proposes a semi-analytical method for thermoelastic lateral-torsional buckling of steel beams subjected to distributed loads and bidirectional thermal gradients. Based on a beam-discrete strategy, the beam is divided into a series of segments, each assumed to have a constant longitudinal temperature. Considering variation of the effective centroid and effective shear center along the beam, each uniform beam segment is connected using noncoaxial nodes. A modular transfer matrix approach, founded on internal force relationships at each node, is then used to assemble the system. The resulting total transfer matrix yields the buckling load or critical temperature for any combination of longitudinal and transverse temperature gradients. In addition, a lumped-capacity method is developed to predict the temperature evolution of steel beams under localized fire conditions. Based on the obtained temperature distributions, the buckling time and critical temperature of the beams are further investigated. The accuracy and versatility of the proposed approach are validated through comparisons with results from existing literature and ANSYS simulations. Parametric studies are conducted to illustrate the effects of selected parameters on the beam’s buckling behavior.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114693"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on nonlinear flutter characteristics of flexible supported photovoltaic systems","authors":"Chunguang Li ,&nbsp;Minhao Zou ,&nbsp;Kai Li ,&nbsp;Peng Hu ,&nbsp;Yan Han ,&nbsp;Lian Shen","doi":"10.1016/j.tws.2026.114699","DOIUrl":"10.1016/j.tws.2026.114699","url":null,"abstract":"<div><div>The flexible photovoltaic (PV) support system utilizesa cable-supported structure for load-bearing, characterized by its lightweight and flexible design. When PV modules are installed at steep angles due to geographical requirements, they exhibit classic bluff body aerodynamics, making them highly susceptible to flutter instability under wind loads. However, systematic studies on the influencing factors and underlying mechanisms of this flutter remain limited . This study is based on an actual large-span flexible PV support project and a comprehensive test investigation was performed using an elastically suspended sectional model in a wind tunnel. The study systematically examines the static wind-induced displacement versus additional tilt angle, the critical flutter wind speed, and the nonlinear flutter response of flexible-support photovoltaic structures, all evaluated over a range of installation angles from -18° to +18° Special emphasis is placed on the influence of vertical vibration participation on the nonlinear flutter characteristics in flexible PV structures with a low bending–torsion frequency ratio, along with an analysis of multistable vibration responses induced by various excitation conditions during testing. Results show that both the wind-induced static displacement and the additional tilt angle of the flexible PV structure increase significantly with wind speed and installation angle. . Typical bending-torsion coupled nonlinear flutter was observed across all tilt angles. Moreover, the level of vertical vibration participation was found to increase with the incoming wind speed but decrease with a greater tilt angle. In tests where vertical degrees of freedom were restricted, the increase in critical flutter wind speed was positively correlated with the degree of vertical vibration contribution compared to two-degree-of-freedom systems. Specifically, when vertical vibration participation is low, the flutter critical wind speed is largely unaffected. However, when participation is high, restricting vertical vibration significantly increases the structure's flutter critical wind speed. Furthermore, a subcritical Hopf bifurcation was observed in the experiments, attributed to the nonlinear characteristics of both structural and aerodynamic damping.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114699"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topology optimization of SPF/DB-formed corrugated sandwich structure with process constraints","authors":"Ming Liu,&nbsp;Hanbin Wang,&nbsp;Wenjiong Chen,&nbsp;Shutian Liu","doi":"10.1016/j.tws.2026.114696","DOIUrl":"10.1016/j.tws.2026.114696","url":null,"abstract":"<div><div>Superplastic forming/diffusion bonding (SPF/DB) is an advanced manufacturing technology to fabricate components with complex geometries. This process enables the production of intricate mechanical structures with enhanced performance, while significantly reducing part count and assembly complexity. However, the mechanical properties of SPF/DB sandwich structures are critically dependent on the topological configuration of their core layers. This highlights the need for a topology optimization methodology specifically adapted to the SPF/DB processes, taking into account relevant manufacturing constraints. In this study, an integrated topology optimization framework for SPF/DB sandwich structures is proposed, which employs the Beluga Whale Optimization (BWO) algorithm to achieve high-performance designs under realistic fabrication limitations. The proposed approach establishes a seamless workflow that integrates modelling, simulation, and optimization, thereby offering a systematic design strategy for SPF/DB structures that rigorously incorporates fabrication limitations. The effectiveness of the method is demonstrated through two illustrative case studies. This work provides valuable guidance for the initial layout design of diffusion bonding regions in lightweight sandwich structures under SPF/DB process constraints. Moreover, it contributes to the broader application of topology optimization techniques in SPF/DB manufacturing.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114696"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Axial compression behavior of square concrete-filled steel tube slender columns with concrete defects","authors":"Jiahang Xu,&nbsp;Ting Zhou,&nbsp;Zhihua Chen,&nbsp;Yutong Zhang","doi":"10.1016/j.tws.2026.114667","DOIUrl":"10.1016/j.tws.2026.114667","url":null,"abstract":"<div><div>Defects formed during concrete casting can degrade the composite action of square concrete-filled steel tube (SCFST) columns, such as interfacial debonding and internal voids. The sensitivity of slender columns to concrete defects differs from that of short columns. This study reports axial compression tests on 34 slender SCFST columns (150 mm × 150 mm × 1500 mm) with five defect types and controlled defect ratios from 0% to 10.12%. The experimental program examines failure modes, load-displacement responses, ultimate capacity, initial stiffness and strain analysis. The disparity between separate distribution (SD) and uniform distribution (UD) defects at equivalent defect ratios is investigated. Results show local outward bulging of the steel tube with crushing of the infilled concrete as the dominant failure mode, while corner-located defects are more prone to induce brittle responses. Capacity reductions range from approximately 0% to 38.50% over the tested defect range. UD defects reduce the bearing capacity more than SD defects under the same defect ratio. The average bearing capacity of slender columns is 7.11% lower than that of short columns with the same defect type and defect ratio, which shows the amplification by second-order effects and the reduction of effective stiffness, especially when defects lie near the mid-height<em>.</em> A three-dimensional FE model is developed and validated against the tests, and a parametric study under pinned-pinned ends is conducted. Based on a validated FE database (63 samples), a unified defect reduction-factor model dependent on defect ratio, distribution pattern, defect type, and relative slenderness is established and incorporated into a defect-adjusted strength formulation. A conservative lower-envelope expression is further provided for design. When the effective length factor is taken as <em>K</em>=0.65 recommended by AISC 360-22, the predictions for 31 defective test specimens show good agreement with the measurements (mean prediction-to-test ratio≈0.997, standard deviation≈0.091).</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"224 ","pages":"Article 114667"},"PeriodicalIF":6.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}