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Ultimately exposed roof area prediction of bauxite deposit goaf based on macro joint damage 认领 引用 被引量：14
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作者 Lichun Jiang Chao Yang Huazhe Jiao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2020年第5期699-704,共6页
The ultimately exposed roof area(UERA)of goaf is crucial to the safety and economics of underground mining.The prediction models do not consider the mechanical weakness of rock mass and ignore the influence of the joi... The ultimately exposed roof area(UERA)of goaf is crucial to the safety and economics of underground mining.The prediction models do not consider the mechanical weakness of rock mass and ignore the influence of the joint damage factor,causing a large predicted exposure area with a high roof falling risk.This work adopted joint damage factor to derive a new UERA prediction model.The relationships between the UERA(S)and the span ratio(m),the density(k)and the diameter of fracture(d)were analysed by the new prediction model.The results showed that the exposed area S and the span ratio m have a U-shaped curve relationship.The S decreases with the increase of m and then increases when m is beyond 2.The exposed roof area S is in an inversely proportional power-law relationship with the fracture surface density k,and the curvature of the S-k relationship curve decreases when d=0.5 and k>7,and S is close to 0.There is a negative correlation between S and the fracture surface diameter d,the curvature of the S-d curve decreases with the increase of d and k,and the variation rate increases first and then decreases with the increase of d;when k=0.5 and d>9,S is close to 0.The predicted values of the UERA prediction model are 119.3,112.8,and 114.6 m2 with different joint damage parameters,which are slightly smaller than the actual critical exposure area of a roof(S=120 m2).The case study shows that the alternative prediction model is reasonable and acceptable and provides new theoretical support for the underground mining safety of sedimentary bauxite ore. 展开更多
关键词 Ultimately exposed roof area Bauxite goaf Prediction model Macro joint damage
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Numerical analysis of the effect of the gradation characteristics of soil particles on the ground bearing capacity of a rigid footing via the discrete element method 认领 引用
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作者 LIU Zong-qi CHEN Xi +2 位作者 CUI Liu-sheng XU Zhe YAN Zhi-kai 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第3期1387-1402,共16页
To underscore the overestimation of the ground bearing capacity by continuum-based numerical or analytical methods,the discrete element method(DEM),which may capture the microscopic characteristics of soil with graded... To underscore the overestimation of the ground bearing capacity by continuum-based numerical or analytical methods,the discrete element method(DEM),which may capture the microscopic characteristics of soil with graded particles,is used to study the ultimate bearing capacity of the ground(p u).In this work,the rolling resistance linear model of contact is implemented by the DEM for the soil,so the ultimate bearing capacity of the ground can be predicted.During the loading process in the DEM test,the development of a failure zone(or shear band)in the ground can be observed.Numerical experiments reveal that there is a certain negative linear relationship between the footing's ultimate rotation angle(αu)and p u,offering a novel perspective on the study of p u.Due to the asymmetry of the DEM ground,a new modification factorηp is defined for the ultimate bearing capacity.It is found that particularly for soils with a large mean particle size,narrow gradation or poor continuity of the particles,the effect of particle gradation characteristics on the ultimate bearing capacity should be appropriately evaluated. 展开更多
关键词 ultimate ground bearing capacity soil with graded particles discrete element method uneven settlement rotation of footing
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Dynamic evolution mechanism of petrophysical properties in shale reservoirs and its petroleum geological significance:A case study of the Cretaceous Lower Eagle Ford Formation,Gulf Coast Basin,USA 认领 引用
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作者 HOU Lianhua ZHAO Zhongying +7 位作者 WU Songtao HOU Mingqiu WANG Zhaoming LIN Senhu YANG Zhi LI Siyang ZHANG Mengyao LUO Xia 《Petroleum Exploration and Development》 SCIE 2026年第2期311-326,共16页
Based on test data,production performance data,logging data and seismic data of shale samples from the Cretaceous Lower Eagle Ford Formation in the Gulf Coast Basin,USA,methods for determining organic matrix porosity ... Based on test data,production performance data,logging data and seismic data of shale samples from the Cretaceous Lower Eagle Ford Formation in the Gulf Coast Basin,USA,methods for determining organic matrix porosity and inorganic matrix porosity were established,and a method for reconstructing the original total organic carbon was developed.Systematic research was conducted by analyzing values across varying intervals of original total organic carbon content,vitrinite reflectance,and clay mineral content.The study demonstrates that shale matrix porosity is primarily controlled by original total organic carbon content and vitrinite reflectance,with organic pores contributing up to 68%to total matrix porosity.A parameter quantifying the organic matrix porosity contribution per unit original total organic carbon is proposed,which can effectively characterize its evolution.As vitrinite reflectance increases,both matrix porosity and effective matrix porosity exhibit a pattern of initial increase,subsequent decrease,and secondary increase before ultimately stabilizing.The ratio of effective-to-total matrix porosity increases from approximately 53%in low-maturity stage to 79%in high-maturity stage.Inorganic matrix porosity remains relatively stable,with clay mineral transformation causing a maximum reduction of approximately 0.62 percentage points.Strong positive correlations are observed between matrix permeability and matrix porosity,as well as between vertical and horizontal permeability,with horizontal permeability being approximately 20 times that of vertical permeability.Fracture porosity is predominantly controlled by the intensity of tectonic activity,and estimated ultimate recovery is jointly governed by hydrocarbon-filled matrix porosity and fracture porosity.The dynamic evolution mechanisms of reservoir properties throughout the entire thermal evolution of shale are revealed,characterized by pore generation and permeability enhancement via organic hydrocarbon generation,porosity-permeability enhancement through tectonic fracturing,porosity reduction due to oil cracking and subsequent pore-filling by pyrobitumen/bitumen,and porosity reduction driven by clay mineral transformation.The established quantitative evaluation models for shale matrix porosity,fracture porosity,and permeability can provide methodological reference for shale reservoir property evaluation. 展开更多
关键词 shale oil and gas reservoir petrophysical properties organic matrix porosity fracture porosity clay mineral content estimated ultimate recovery Cretaceous Eagle Ford Formation Gulf Coast Basin of USA
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Twin tunnel stability and support requirements:Insights from limit analysis 认领 引用 被引量：1
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作者 Aayush KUMAR Vinay Bhushan CHAUHAN 《Journal of Mountain Science》 SCIE CSCD 2026年第1期394-416,共23页
Urban tunnels are often built in multiples,yet the influence of surface structures on their support demands is frequently overlooked,highlighting the need for refined design under realistic loading.This study addresse... Urban tunnels are often built in multiples,yet the influence of surface structures on their support demands is frequently overlooked,highlighting the need for refined design under realistic loading.This study addresses this gap by examining the response of a uniformly loaded strip footing above twin horseshoe tunnels with structural linings.A non-dimensional Footing Stability Improvement Factor(If),defined as the ratio of ultimate bearing capacity with and without lining to that of a footing on intact rock—is evaluated using adaptive finite element limit analysis.The effects of normalized vertical depth of tunnel,normalised horizontal spacing of tunnel,and lining-thickness factor are examined,providing key insights into foundation-tunnel interaction and support optimization.This study finds that,for unlined twin tunnels,footing-tunnel interaction becomes negligible when embedment exceeds four times of footing widths and tunnel spacing surpasses eleven times of footing widths,beyond which additional support is unnecessary.For lined tunnels,the tunnel-lining thickness required to maintain footing stability equivalent to that on intact rock decreases rapidly with embedment depth.At a tunnel spacing equal to onehalf of the footing width,the critical lining-thickness ratio is about six percent of the footing width at a tunnel depth of half the footing width,reducing to approximately five,four,and three percent at depths of one,one-and-a-half,and two footing widths,and asymptotically approaching nearly one percent for embedment depths exceeding two-and-a-half footing widths.Additionally,rock mass parameters exhibit minimal impact(±2%)on If.The results show that failure mechanisms in footing-tunnel systems are primarily governed by tunnels-positional parmeters,and lining thickness.The study presents a mechanistic framework that delineates the critical depth-spacing-thickness regimes controlling twin-tunnel behavior,providing engineers with clear design boundaries and performance-based lining guidelines to improve the stability of both tunnels and overlying foundations. 展开更多
关键词 Horseshoe tunnel Tunnel lining Strip footing Adaptive Finite element limit analysis Rock engineering Ultimate bearing capacity
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Reservoir Characteristics and Production Performance of Shale Oil in the MX Block,the Fengcheng Formation,Mahu Sag,China 认领 引用
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作者 Lin Chen Anqi Zhao +6 位作者 Yunpei Zhang Sai-Mi-La XiaFuKaiTi Yao Qin Chuan Wang Gang Chen Jiqiang Li Shilai Hu 《Energy Engineering》 EI 2026年第5期461-481,共21页
The shale oil resources in the Permian Fengcheng Formation of the Mahu Sag exhibit significant potential but are characterized by strong heterogeneity and complex production dynamics,posing challenges for development.... The shale oil resources in the Permian Fengcheng Formation of the Mahu Sag exhibit significant potential but are characterized by strong heterogeneity and complex production dynamics,posing challenges for development.This study conducts a comprehensive analysis of the reservoir characteristics and production performance of the shale oil reservoir in the second member of the Fengcheng Formation within the MX Block.Utilizing data from three appraisal wells(M1X,M2X,M3H),we systematically evaluated the geological structural features,sedimentary characteristics,complex mineralogy,and petrophysical properties of the reservoir.The production dynamics of all wells display a multi-stage decline behavior,indicative of a dual-control flow mechanism dominated by both fracture networks and matrix supply.Based on wellhead pressure and production data,the production lifecycle can be divided into three distinct stages,with the final stage governing the long-term production potential and Estimated Ultimate Recovery(EUR).To address the challenge of predicting EUR in such multi-stage production,integrate Blasingame type-curve analysis to identify the start of the boundary-dominated flow regime and employ a hyperbolic decline model fitted via the Levenberg-Marquardt algorithm for forecasting.The EURs of the three appraisal wells were successfully predicted,all exceeding 40,000 t,confirming the commercial viability of the reservoir.The findings highlight the critical roles of optimized fracturing design,appropriate well type selection,and controlled initial production rates in enhancing recovery.This research provides a robust technical framework for evaluating development potential and formulating effective development strategies for similar shale oil reservoirs. 展开更多
关键词 Shale oil reservoir characteristics production performance decline curve analysis estimated ultimate recovery Fengcheng Formation
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Ultimate Strength Evaluation of Urban Underground UPVC Pipelines Considering Effects of High-Temperatures 认领 引用
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作者 Bin Chen Wanli Cui +2 位作者 Wenhui Li Jiachen Yu Zhanzhan Tang 《Structural Durability & Health Monitoring》 EI 2026年第4期286-298,共13页
The outstanding performance of unplasticized polyvinyl chloride(UPVC)has led to its widespread use in urban underground pipeline systems.However,understanding the effects of high-temperature industrial wastewater on t... The outstanding performance of unplasticized polyvinyl chloride(UPVC)has led to its widespread use in urban underground pipeline systems.However,understanding the effects of high-temperature industrial wastewater on the buried pipes is very complicated.To investigate the influence of industrial wastewater on the safety of pipes,the mechanical properties were tested using the material specimens.The changes in mechanical properties caused by the environmental temperature and heat cycleswere experimentally analyzed.Empirical formulas to predict the mechanical parameters of UPVC pipe material were proposed.The ultimate strength of underground urban pipes was numerically studied by the parametric analysis.Results show that themaximum stress and ductility of UPVC pipe material decrease significantly as the ambient temperature and heat cycle increase.The ultimate strength of the underground pipe decreases exponentially with the increase in the ambient temperature.Both the temperature amplitude and the number of heat cycles have significant influences on the performance of the underground pipes. 展开更多
关键词 Ultimate strength polyvinyl chloride urban pipes high-temperature industrial wastewater mechanical-property
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Lava Ultimate优韧瓷高嵌体修复牙体缺损对龈沟液炎症损伤与微生物学指标及咀嚼功能的影响 认领 引用
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作者 赵文 郑海霞 +1 位作者 贺娟 王锦华 《中国美容医学》 CAS 2026年第7期157-161,共5页
目的:探讨Lava Ultimate优韧瓷高嵌体修复牙体缺损对龈沟液炎症损伤指标、微生物学指标及咀嚼功能的影响。方法:选取笔者科室2021年1-2024年6月收治的120例牙体缺损患者,根据治疗方法不同将患者分为观察组(60例)及对照组(60例),观察组行... 目的:探讨Lava Ultimate优韧瓷高嵌体修复牙体缺损对龈沟液炎症损伤指标、微生物学指标及咀嚼功能的影响。方法:选取笔者科室2021年1-2024年6月收治的120例牙体缺损患者,根据治疗方法不同将患者分为观察组(60例)及对照组(60例),观察组行Lava Ultimate优韧瓷高嵌体修复治疗,对照组行铸瓷嵌体修复治疗。比较两组患者的龈沟液炎症指标[白介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、天门冬氨酸氨基转移酶(AST)]、微生物学指标、咀嚼功能、抗折能力,以及牙周指标[探诊深度(PD)、牙齿松动度(PTV)、菌斑指数(PLI)、牙龈指数(GI)]、美观度和并发症。结果:修复后,两组龈沟液IL-1β、TNF-α、AST水平均高于修复前,但观察组各指标水平均低于对照组(均P0.05)。两组修复后PD均高于修复前(P<0.05),GI、PLI均低于修复前(P<0.05),且观察组PD高于对照组(P<0.05),GI、PLI低于对照组(P<0.05);观察组修复体颜色、外形、舒适度满意率均高于对照组(P<0.05)。观察组并发症发生率低于对照组(P<0.05)。结论:采用Lava Ultimate优韧瓷高嵌体修复牙体缺损能够减轻牙龈炎症损伤,维持牙龈微生物学功能,促使咀嚼功能的恢复,且患者满意度较高,并发症较少。 展开更多
关键词 牙体缺损 牙体修复 Lava Ultimate优韧瓷高嵌体 炎症损伤 微生物学
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猛士M817 Ultimate 认领 引用
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《汽车观察》 2026年第2期84-84,共1页
延续“雄魂美学2.0”,采用撕裂式獠牙格栅、隆起式高能量罩、碳纤维负压风道+C柱猎豹勋章饰板,搭配35英寸越野大脚+氮气减震,硬派质感拉满;宝矿蓝专属色采用流光彩漆、铝镁合金饰板等高端工艺,质感越级。搭载磐石底盘2.0+896线激光雷达... 延续“雄魂美学2.0”,采用撕裂式獠牙格栅、隆起式高能量罩、碳纤维负压风道+C柱猎豹勋章饰板,搭配35英寸越野大脚+氮气减震,硬派质感拉满;宝矿蓝专属色采用流光彩漆、铝镁合金饰板等高端工艺,质感越级。搭载磐石底盘2.0+896线激光雷达,实现非铺装路面NCA智能驾驶,精准预判路况、智能分配扭矩,国道行驶可实现0接管,展现出强悍的智能越野核心能力。 展开更多
关键词 猛士M817 Ultimate 隆起式高能量罩
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Einstein The Amp Ultimate Black Serises合并式功放 认领 引用
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《视听前线》 2026年第5期60-61,共2页
Einstein Audio Components成立于1988年,由录音师VolkerBohlmeier与技术专家Rolf Weiler共同创立。其产品涵盖功放、唱盘、音箱等等。The Amp Ultimate Black Series(MK108)是一款采用Circlotron电路的纯A类设计混合功放,具备双单声道... Einstein Audio Components成立于1988年,由录音师VolkerBohlmeier与技术专家Rolf Weiler共同创立。其产品涵盖功放、唱盘、音箱等等。The Amp Ultimate Black Series(MK108)是一款采用Circlotron电路的纯A类设计混合功放,具备双单声道架构、低失真与高动态性能,兼具极简美学和顶级音质,是Einstein品牌追求完美声音的代表作。 展开更多
关键词 The Amp Ultimate Black Series
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放大器 认领 引用
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《视听前线》 2026年第6期33-35,共3页
Einstein The Amp Ultimate Black Serises合并式功放产品代理:威虹音响The Amp Ultimate Black Series(MK108)是一款采用Circlotron电路的纯A类设计混合功放,具备双单声道架构、低失真与高动态性能,兼具极简美学和顶级音质,是德国Einst... Einstein The Amp Ultimate Black Serises合并式功放产品代理:威虹音响The Amp Ultimate Black Series(MK108)是一款采用Circlotron电路的纯A类设计混合功放,具备双单声道架构、低失真与高动态性能,兼具极简美学和顶级音质,是德国Einstein品牌追求完美声音的代表作。透明的中频与精准的低频是它的特长,人声细腻温润,弦乐光泽感十足,打击乐瞬态凌厉却不失层次,动态起伏间始终保持平衡。 展开更多
关键词 The Amp Ultimate Black Series
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Comparison of respiratory mechanics measurement between pressure-controlled ventilation and volumecontrolled ventilation 认领 引用
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作者 Zhi’ang Li Peifang Li +4 位作者 Yiling Jiang Jianjun Zhu Jianliang Zhu Zhiping Xu Lijun Liu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2025年第1期78-81,共4页
Mechanical ventilation is a specialized oxygen therapy and life support technology with significant importance for critically ill patients.In fact,40%–66%of patients in the intensive care unit(ICU)require mechanical ... Mechanical ventilation is a specialized oxygen therapy and life support technology with significant importance for critically ill patients.In fact,40%–66%of patients in the intensive care unit(ICU)require mechanical ventilation.[1,2]However,the mechanical ventilation can lead to ventilatorassociated lung injury(VALI),[3]ultimately resulting in difficulties in weaning from mechanical ventilation,prolonged hospital stays,and even increased mortality. 展开更多
关键词 specialized ventilation ultimately
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Optimizing strength-ductility in NiCoMn medium entropy alloys with atomic-scale rapid composition design 认领 引用 被引量：1
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作者 Qing Gao Weibing Wang +6 位作者 Junqiang Ren Wei Li Biao Sang Le Li Qi Wang Xuefeng Lu Jisen Qiao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2025年第12期71-85,共15页
The growing demand for material properties in challenging environments has led to a surge of interest in rapid composition design. Given the great potential composition space, the field of high/medium entropy alloys (... The growing demand for material properties in challenging environments has led to a surge of interest in rapid composition design. Given the great potential composition space, the field of high/medium entropy alloys (H/MEAs) still lacks effective atomic-scale composition design and screening schemes, which hinders the accurate prediction of desired composition and properties. This study proposes a novel approach for rapidly designing the composition of materials with the aim of overcoming the trade-off between strength and ductility in metal matrix composites. The effect of chemical composition on stacking fault energy (SFE), shear modulus, and phase stability was investigated through the use of molecular dynamics (MD) and thermodynamic calculation software. The alloy's low SFE, highest shear modulus, and stable face-centered cubic (FCC) phase have been identified as three standard physical quantities for rapid screening to characterize the deformation mechanism, ultimate tensile strength, phase stability, and ductility of the alloy. The calculation results indicate that the optimal composition space is expected to fall within the ranges of 17 %–34 % Ni, 33 %–50 % Co, and 25 %–33 % Mn. The comparison of stress-strain curves for various predicted components using simulated and experimental results serves to reinforce the efficacy of the method. This indicates that the screening criteria offer a necessary design concept, deviating from traditional strategies and providing crucial guidance for the rapid development and application of MEAs. 展开更多
关键词 Medium entropy alloys Molecular dynamics Stacking fault energy Shear modulus Ultimate tensile strength Ductility
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The role of γ/γ interfacial spacing on the tensile behavior in lamellar TiAl alloy via molecular dynamics simulations 认领 引用 被引量：1
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作者 Xiong Zhou Shiping Wang +6 位作者 Zhongtao Lu Xiege Huang Xiaobin Feng Jiayi Fu Wenjuan Li Pengcheng Zhai Guodong Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2025年第2期1-6,共6页
The lamellar microstructure is one of the most typical microstructures of TiAl alloys.There are threeγ/γinterfaces with different microstructures in lamellarγ-TiAl alloys.In this work,we investigated the deformatio... The lamellar microstructure is one of the most typical microstructures of TiAl alloys.There are threeγ/γinterfaces with different microstructures in lamellarγ-TiAl alloys.In this work,we investigated the deformation processes of lamellarγ-TiAl alloys with different interfacial spacing(λ)via uniaxial tensile loading using molecular dynamics simulations,including true twin(TT),pseudo-twin(PT),rotational boundary(RB),and the mixed structure(TT∥PT∥RB).The results show that in all lamellarγ-TiAl samples,the Shockley partial dislocation prefers to nucleate in the region between two neighboring interfaces.Then,dislocations move towards,crossing theγ/γinterface.Finally,the dislocation slippage leads to the destruction of the interface,resulting in cracks and structural failure.With the decrease ofλ,the ultimate strength slightly increases in the TT or PT structure ofγ-TiAl,which follows the Hall-Petch relation.But in general,the interfacial spacing has a slight effect on the ultimate strengths of these four structures ofγ-TiAl. 展开更多
关键词 Lamellarγ-TiAl alloys γ/γinterface Ultimate strength Interfacial spacing
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Online Fault-Tolerant Tracking Control With Adaptive Critic for Nonaffine Nonlinear Systems 认领 引用 被引量：1
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作者 Ding Wang Lingzhi Hu +1 位作者 Xiaoli Li Junfei Qiao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2025年第1期215-227,共13页
In this paper, a fault-tolerant-based online critic learning algorithm is developed to solve the optimal tracking control issue for nonaffine nonlinear systems with actuator faults.First, a novel augmented plant is co... In this paper, a fault-tolerant-based online critic learning algorithm is developed to solve the optimal tracking control issue for nonaffine nonlinear systems with actuator faults.First, a novel augmented plant is constructed by fusing the system state and the reference trajectory, which aims to transform the optimal fault-tolerant tracking control design with actuator faults into the optimal regulation problem of the conventional nonlinear error system. Subsequently, in order to ensure the normal execution of the online learning algorithm, a stability criterion condition is created to obtain an initial admissible tracking policy. Then, the constructed model neural network(NN) is pretrained to recognize the system dynamics and calculate trajectory control. The critic and action NNs are constructed to output the approximate cost function and approximate tracking control,respectively. The Hamilton-Jacobi-Bellman equation of the error system is solved online through the action-critic framework. In theoretical analysis, it is proved that all concerned signals are uniformly ultimately bounded according to the Lyapunov principle.The tracking control law can approach the optimal tracking control within a finite approximation error. Finally, two experimental examples are conducted to indicate the effectiveness and superiority of the developed fault-tolerant tracking control scheme. 展开更多
关键词 Adaptive critic control neural network(NN) nonaffine nonlinear systems online fault-tolerant tracking design uniform ultimate boundedness
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Research on the Ultimate Strength of a Hull Bottom Full-Scale Stiffened Plate Under Axial Compression and Lateral Pressure 认领 引用 被引量：1
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作者 LI Zheng-jie DING Qi-yin +1 位作者 CUI Hu-wei ZHAO Nan 《China Ocean Engineering》 SCIE EI CSCD 2025年第1期1-12,共12页
The influences of different factors,including whether the transverse frames are actually built,longitudinal and transverse welding residual stresses,and unloaded edge boundaries,on the ultimate strength and failure mo... The influences of different factors,including whether the transverse frames are actually built,longitudinal and transverse welding residual stresses,and unloaded edge boundaries,on the ultimate strength and failure mode of a real hull bottom full-scale stiffened plate under axial compression and lateral pressure are investigated via numerical analysis.Result shows that the failure mode of the stiffened plate under axial compression is the tripping of the stiffeners.Whether transverse frames are built has little effect on the ultimate strength of the stiffened plate under axial compression,which can be replaced by the degree of freedom constraint.However,when lateral pressure is present,the transverse frame cannot be simply replaced by a free-degree constraint.The longitudinal residual stress has a greater effect on the ultimate strength,whereas the effect of the transverse residual stress is smaller.Stronger unloaded edge boundary conditions can slightly enhance the stiffness and ultimate strength of the stiffened plate.Under combined axial compression and lateral pressure,the failure mode of stiffened plates changes from the tripping of stiffeners to beam-column failure,as the lateral pressure increases.The ability of stiffened plates in which transverse frames are actually built out to resist beam-column shape deformation becomes weaker with lower ultimate strength.Stronger unloaded edge boundary conditions can improve the ability of stiffened plates to resist beam-column deformation and increase the ultimate strength. 展开更多
关键词 ultimate strength full-scale stiffened plate residual stress lateral pressure
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Lava Ultimate优韧瓷与铸瓷高嵌体修复牙体缺损的效果及其对龈沟液炎症指标、远期保存率的影响 认领 引用 被引量：1
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作者 金文静 吴迪 张杰夫 《川北医学院学报》 CAS 2025年第7期918-921,926,共4页
目的:探讨Lava Ultimate优韧瓷与铸瓷高嵌体修复牙体缺损的效果及对龈沟液炎症指标、远期保存率的影响。方法:选取122例牙体缺损患者为研究对象,依据治疗方法不同分为优韧瓷组和铸瓷组,每组各61例。优韧瓷组患者予以Lava Ultimate优韧... 目的:探讨Lava Ultimate优韧瓷与铸瓷高嵌体修复牙体缺损的效果及对龈沟液炎症指标、远期保存率的影响。方法:选取122例牙体缺损患者为研究对象,依据治疗方法不同分为优韧瓷组和铸瓷组,每组各61例。优韧瓷组患者予以Lava Ultimate优韧瓷高嵌体修复治疗;铸瓷组予以铸瓷高嵌体修复治疗。比较两组患者修复前及修复6个月后的牙周状况、龈沟液炎症指标及修复2年后的修复效果和红色美学指数评分。结果:修复6个月后,两组患者牙周状况、龈沟液炎症指标均改善(P0.05);修复2年后,优韧瓷组患者牙体完整性、软组织形态优于铸瓷组(P<0.05);铸瓷组软组织颜色优于优韧瓷组(P<0.05)。结论:Lava Ultimate优韧瓷与铸瓷高嵌体修复牙体缺损患者均有较好效果,可改善牙周状况和牙龈炎症反应,但铸瓷高嵌体修复颜色更好,而Lava Ultimate优韧瓷高嵌体修复牙体完整性、软组织形态更优,临床可根据患者意愿选择合适修复材料。 展开更多
关键词 Lava Ultimate优韧瓷 铸瓷 高嵌体修复 牙体缺损 炎症指标
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Cyclic Response Characteristics of Rigid Piles in Dense Sand Under One-way Oblique Tensile Loads 认领 引用
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作者 HUANG Ting DAI Guo-liang +2 位作者 TIAN Ying-hui ZHANG Ji-sheng XU Qing-yun 《China Ocean Engineering》 SCIE EI CSCD 2025年第4期698-707,共10页
The behavior of rigid piles in sandy soils under one-way cyclic oblique tensile loading represents a critical design consideration for floating renewable devices.These piles,when moored with catenary or taut moorings,... The behavior of rigid piles in sandy soils under one-way cyclic oblique tensile loading represents a critical design consideration for floating renewable devices.These piles,when moored with catenary or taut moorings,experience one-way cyclic tensile loads at inclinations ranging from 0°(horizontal)to 90°(vertical).However,the combined effects of cyclic loading and load inclination remain inadequately understood.This study presents findings from centrifuge tests conducted on rough rigid piles installed in dense sand samples.The results demonstrate that load inclinations significantly influence both cyclic response and ultimate capacity of the piles.Based on the observed cyclic response characteristics,the vertical cyclic load amplitude should not exceed 25%of the ultimate bearing capacity to maintain pile stability.A power expression(with exponent m values ranging from 0.055 to 0.065)is proposed for predicting cumulative pile displacement under unidirectional cyclic loading at inclinations from 0°to 60°.The cyclic response exhibits reduced sensitivity to horizontal cyclic load magnitude,with m-value increasing from 0.06 to 0.14 as load magnitude increases from 0.3 to 0.9.For piles maintaining stability under oblique cyclic loading,the average normalized secant stiffness exceeds 1 and increases with decreasing inclination,indicating enhanced pile stiffness under cyclic loading.For load inclinations below 30°,pile stiffness can be determined using logarithmic function. 展开更多
关键词 pile centrifuge test oblique load ultimate capacity cyclic response power expression stiffness
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Model experimental study on the safety characteristics of surrounding rock supports in deep wells 认领 引用
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作者 Renshu Yang Feixiang Lu +3 位作者 Xinmin Ma Liyun Yang Yiyin Hu Shuo Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2025年第12期2866-2879,共14页
To study the use of a shaft support for the auxiliary shaft of the Xi’anshan Iron Mine,in high-stress strata at a depth between 900 and 1000 m,a new type of mold was developed using the physical similarity model test... To study the use of a shaft support for the auxiliary shaft of the Xi’anshan Iron Mine,in high-stress strata at a depth between 900 and 1000 m,a new type of mold was developed using the physical similarity model test method,based on the similarity theory,and an experimental model of the shaft lining and surrounding rock was poured.Two sets of large-scale destructive tests were conducted on the shaft lining and surrounding rock.The deformation and failure laws of the shaft lining and surrounding rock under high ground stress and their ultimate horizontal bearing capacity characteristics were studied,and the safety support characteristics of the shaft lining under the interaction of the shaft lining and surrounding rock were obtained.An experimental study demonstrated that the axial pressure on the shaft wall directly affected its ultimate horizontal bearing capacity of the shaft wall.In designing the shaft wall,the influence of the axial pressure on the stress state of the concrete should be considered,and the vertical pressure should be modified to optimize the utilization of the three-dimensional compressive strength of the concrete.The reliability of the 400-mm C30 concrete shaft wall at a depth of 1000 m in the actual project was verified,and the ultimate horizontal bearing capacity of the shaft wall was obtained for a depth of 1000 m. 展开更多
关键词 physical similarity model high ground stress shaft support ultimate bearing capacity law of destruction
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In-Plane Bearing Capacity of CFST Truss Arch Bridges with Geometric Defects 认领 引用
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作者 Chao Luo Zhengsong Xiang +3 位作者 Yin Zhou Dingsong Qin Tianlei Cheng Qizhi Tang 《Structural Durability & Health Monitoring》 EI 2025年第3期683-703,共21页
Failure tests were conducted on two concrete-filled steel tubular(CFST)truss arch bridges with a span of approximately 12 m to investigate the influence of initial geometric defects on the in-plane bearing capacity of... Failure tests were conducted on two concrete-filled steel tubular(CFST)truss arch bridges with a span of approximately 12 m to investigate the influence of initial geometric defects on the in-plane bearing capacity of CFST truss arch bridges.The effects of antisymmetric defect on the ultimate bearing capacity,failure mode,structural response,and steel–concrete confinement effect of CFST truss arch bridges under quarter-point loading were analyzed.On this basis,numerical simulations were conducted to investigate the in-plane bearing capacity of CFST truss arch bridges further under different scenarios.The initial defect formof the archwas obtained by using theoretical deduction,and the theoretical basis for the weakening of the ultimate bearing capacity of the arch bridge caused by geometric defects was clarified.Results indicate that the antisymmetric defect does not change the four-hinge failure mode of the model arch under quarter-point loading but increases the local cracking area and crack density of the concrete inside the pipe.The sine geometric defect with an amplitude of L/250 resulted in a 44.4%decrease in the yield load of the single hinge of the model arch,a 10.5%decrease in the failure load of the four hinges,and a 40.9%increase in themaximum vertical deformation during failure.At the initial stage of loading,the steel pipe and the concrete inside the pipe were subjected to relatively independent forces.After reaching 67%of the ultimate load,the catenary arch ribs began to produce a steel pipe concrete constraint effect.The initial geometric defects resulted in a decrease in the load when the constraint effect occurred.The antisymmetric defects with the same amplitude have a greater impact on the in-plane bearing capacity of the CFST arch bridge than the initial geometric defects with symmetry.The linear deviation at L/4 caused by constructionmust be controlled to be less than L/600 to ensure that the internal bearing capacity of the CFST arch bridge reaches 95%of the design bearing capacity.The structural deformation caused by geometric initial defects increases linearly with the increase in defect amplitude.The bearing capacity is weakened because the structural deflection and bending moment are amplified by initial defects. 展开更多
关键词 Geometric defects CFST arch bridge ultimate bearing capacity model test numerical simulation theoretical derivation
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Lava Ultimate优韧瓷与E-max铸瓷高嵌体在根管治疗后大面积牙体缺损修复中的应用效果比较 认领 引用 被引量：1
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作者 王娴 《中国民康医学》 2025年第22期148-150,共3页
目的:比较Lava Ultimate优韧瓷与E-max铸瓷高嵌体在根管治疗后大面积牙体缺损修复中的应用效果。方法:回顾性分析2022年1月至2023年10月该院收治的90例根管治疗后大面积牙体缺损患者的临床资料,根据修复方法不同将其分为对照组和观察组... 目的:比较Lava Ultimate优韧瓷与E-max铸瓷高嵌体在根管治疗后大面积牙体缺损修复中的应用效果。方法:回顾性分析2022年1月至2023年10月该院收治的90例根管治疗后大面积牙体缺损患者的临床资料,根据修复方法不同将其分为对照组和观察组各45例。对照组应用E-max铸瓷高嵌体修复,观察组应用Lava Ultimate优韧瓷高嵌体修复,比较两组修复疗效,治疗前后咀嚼效率、牙周指标(牙龈指数、菌斑指数)水平,以及修复满意度评分。结果:两组治疗总有效率比较,差异无统计学意义(P>0.05);治疗后,两组咀嚼效率均高于治疗前,但组间比较,差异无统计学意义(P>0.05);治疗后,两组牙龈指数、菌斑指数均低于治疗前,但组间比较,差异均无统计学意义(P>0.05);观察组修复满意度评分高于对照组,差异有统计学意义(P<0.05)。结论:Lava Ultimate优韧瓷高嵌体应用于根管治疗后大面积牙体缺损修复可提高修复满意度评分,效果优于E-max铸瓷高嵌体,其余临床指标效果二者相当。 展开更多
关键词 牙体缺损 修复 Lava Ultimate优韧瓷 E-max铸瓷 高嵌体
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