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Analysis of the Application of Static Load Test in Bridge Bearing Capacity Testing
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作者 Wei Fu Bo Liu 《Journal of Architectural Research and Development》 2024年第3期36-41,共6页
This article uses real engineering projects as examples to analyze how static load test technology is applied in testing the bridge-bearing capacity.The analysis covers aspects such as testing section layout,test load... This article uses real engineering projects as examples to analyze how static load test technology is applied in testing the bridge-bearing capacity.The analysis covers aspects such as testing section layout,test load and efficiency coefficient,loading plan,evaluation optimization,test result modification,and result evaluation.The aim is to support the accurate detection and evaluation of bridge-bearing capacity. 展开更多
关键词 Bridge engineering Bearing capacity Static load test Loading plan test evaluation
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Functional Capacity of Patients with Venous Thromboembolic Disease Six to Twelve Months after Treatment
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作者 Hamadou Bâ Chris-Nadège Nganou-Gnindjio +3 位作者 Alexis Noé S. Guiakam Kemnang Yemele Honore Danwe Dieudonné Guy S. Wafeu 《World Journal of Cardiovascular Diseases》 CAS 2024年第2期88-98,共11页
Background: Venous thromboembolism (VTE) is among the leading causes of hospital-related disability-adjusted life years lost. We aimed to determine the prevalence and determinants of functional capacity impairment six... Background: Venous thromboembolism (VTE) is among the leading causes of hospital-related disability-adjusted life years lost. We aimed to determine the prevalence and determinants of functional capacity impairment six to twelve months after an acute VTE event. Methods: This was a cross-sectional study conducted between January and April 2021 in two referral hospitals of Yaoundé, including consenting adult patients admitted to these hospitals six to twelve months ago for VTE. We excluded dead patients and those with any comorbidity or symptoms limiting physical activity. The functional outcome was assessed with the six-minute walk test. Functional capacity impairment was defined as walking distance lower than the expected value. Results: We included 27 cases in this study with a mean age of 53.2 ± 14.4 years. The prevalence of functional capacity impairment was 29.6% (95% CI: 14.8 - 48.1). Factors associated with poor functional outcome were obesity (OR: 59.5;95% CI: 4.6 - 767.2;p - 207.4;p = 0.017), massive PE (OR: 30;95% CI: 2.5 - 354;p = 0.004), and poor adherence to treatment (OR: 30.3;95% CI: 2.5 - 333.3;p = 0.004). Conclusion: Functional capacity impairment is common in the medium-term after VTE and factors associated with this poor outcome are obesity, the severity of the VTE, and poor adherence to treatment. 展开更多
关键词 Functional capacity Venous Thromboembolism Six-Minute Walk test Cameroon
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Fast Remaining Capacity Estimation for Lithium-ion Batteries Based on Short-time Pulse Test and Gaussian Process Regression 被引量:1
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作者 Aihua Ran Ming Cheng +7 位作者 Shuxiao Chen Zheng Liang Zihao Zhou Guangmin Zhou Feiyu Kang Xuan Zhang Baohua Li Guodan Wei 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期238-246,共9页
It remains challenging to effectively estimate the remaining capacity of the secondary lithium-ion batteries that have been widely adopted for consumer electronics,energy storage,and electric vehicles.Herein,by integr... It remains challenging to effectively estimate the remaining capacity of the secondary lithium-ion batteries that have been widely adopted for consumer electronics,energy storage,and electric vehicles.Herein,by integrating regular real-time current short pulse tests with data-driven Gaussian process regression algorithm,an efficient battery estimation has been successfully developed and validated for batteries with capacity ranging from 100%of the state of health(SOH)to below 50%,reaching an average accuracy as high as 95%.Interestingly,the proposed pulse test strategy for battery capacity measurement could reduce test time by more than 80%compared with regular long charge/discharge tests.The short-term features of the current pulse test were selected for an optimal training process.Data at different voltage stages and state of charge(SOC)are collected and explored to find the most suitable estimation model.In particular,we explore the validity of five different machine-learning methods for estimating capacity driven by pulse features,whereas Gaussian process regression with Matern kernel performs the best,providing guidance for future exploration.The new strategy of combining short pulse tests with machine-learning algorithms could further open window for efficiently forecasting lithium-ion battery remaining capacity. 展开更多
关键词 capacity estimation data-driven method Gaussian process regression lithium-ion battery pulse tests
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PV Capacity Evaluation Using ASTM E2848: Techniques for Accuracy and Reliability in Bifacial Systems
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作者 Gautam Swami Kajal Sheth Dhvanil Patel 《Smart Grid and Renewable Energy》 2024年第9期201-216,共16页
A variety of test methodologies are commonly used to assess if a photovoltaic system can perform in line with expectations generated by a computer simulation. One of the commonly used methodologies across the PV indus... A variety of test methodologies are commonly used to assess if a photovoltaic system can perform in line with expectations generated by a computer simulation. One of the commonly used methodologies across the PV industry is an ASTM E2848. ASTM E2848-13, 2023 test method provides measurement and analysis procedures for determining the capacity of a specific photovoltaic system built in a particular place and in operation under natural sunlight. This test method is mainly used for acceptance testing of newly installed photovoltaic systems, reporting of DC or AC system performance, and monitoring of photovoltaic system performance. The purpose of the PV Capacity Test and modeled energy test is to verify that the integrated system formed from all components of the PV Project has a production capacity that achieves the Guaranteed Capacity and the Guaranteed modeled AEP under measured weather conditions that occur when each PV Capacity Test is conducted. In this paper, we will be discussing ASTM E2848 PV Capacity test plan purpose and scope, methodology, Selection of reporting conditions (RC), data requirements, calculation of results, reporting, challenges, acceptance criteria on pass/fail test results, Cure period, and Sole remedy for EPC contractors for bifacial irradiance. 展开更多
关键词 Photovoltaic System capacity ASTM E2848 Bifacial PV Modules PV capacity testing PVSyst Simulation Solar Energy Performance Regression Modeling
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An Assessment of Cardiovascular Functional Capacity of a Group of Chronic Heart Failure Patients Using the 6-Minute Walk Test in a Cameroonian Urban Setting
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作者 Félicité Kamdem Chris Nadège Nganou-Gnindjio +10 位作者 Dieudonné Danwe Franc Christ-Roi Soemessabot Elysée Claude Bika Léle Ba Hamadou Sidick Mouliom Lade Viché Henri Ngoté Caroline Kenmegne Marie Solange Ndom Ebongue Siddikatou Djibrilla William Ngatchou 《World Journal of Cardiovascular Diseases》 2023年第6期275-282,共8页
Background: Chronic heart failure is a public health problem worldwide. It has a high mortality rate and is accompanied by a decreased functional capacity and alteration of the quality of life. Objective: This st... Background: Chronic heart failure is a public health problem worldwide. It has a high mortality rate and is accompanied by a decreased functional capacity and alteration of the quality of life. Objective: This study aimed to assess the cardiovascular functional capacity of a group of patients suffering from heart failure using the 6-minute walk test (6 MWT). Methods: This was a cross-sectional study carried out in the cardiology unit of Douala’s general hospital for 4 months. We included all eligible patients aged 18 years or more who had stable chronic heart failure and gave informed consent. Those who had an acute coronary syndrome (≤1 month), tachycardia (HR ≥ 120 bpm), high blood pressure (SBP ≥ 180 mmHg and/or DBP ≥ 100 mmHg) and reduced mobility due to orthopaedic reasons were excluded. A 6 MWT was done according to the American Thoracic Society guidelines. The 6 MWT result was considered poor for - 450 m and good for >450 m. Results: We recruited a total of 81 patients (61.7% women) with a mean age of 65.9 ± 10.6 years. The most frequent risk factor for heart failure was high blood pressure (77.8%), alcohol consumption(69.1%) and a sedentary lifestyle (53.1%). The left ventricular ejection fraction was mostly preserved (42.0%) or mildly altered (46.9). The 6 MWT results were poor in 55.6% of cases, average in 19.8% of cases and good in only 24.7% of cases. More than half (59.3%) of the participants perceived the effort as being difficult. The cardiovascular functional capacity was significantly associated with age, heart failure stage and physical activity (p Conclusion: Most patients suffering from chronic stable heart failure in the general hospital of Douala have poor cardiovascular functional capacity. 展开更多
关键词 Cardiovascular Functional capacity Chronic Heart Failure 6-Minute Walk test Cameroon
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Deceleration Capacity--A Novel Measure for Autonomic Nervous System in Patients with Vasovagal Syncope on Tilt-table Testing 被引量:9
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作者 黄芬 徐春芳 +5 位作者 邓小燕 左萍 林凡 樊静静 徐文佳 杨晓云 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第3期326-331,共6页
This study was to investigate the changes of autonomic nerve function and hemodynamics in patients with vasovagal syncope(VVS) during head-up tilt-table testing(HUT). HUT was performed in 68 patients with unexplained ... This study was to investigate the changes of autonomic nerve function and hemodynamics in patients with vasovagal syncope(VVS) during head-up tilt-table testing(HUT). HUT was performed in 68 patients with unexplained syncope and 18 healthy subjects served as control group. According to whether bradycardia, hypotension or both took place during the onset of syncope, the patients were divided during the test into three subgroups: vasodepressor syncope(VD), cardioinhibitory syncope(CI) and mixed syncope(MX) subgroups. Heart rate, blood pressure, heart rate variability(HRV), and deceleration capacity(DC) were continuously analyzed during HUT. For all the subjects with positive responses, the normalized low frequency(LFn) and the LF/HF ratio markedly decreased whereas normalized high frequency(HFn) increased when syncope occurred. Syncopal period also caused more significant increase in the power of the DC in positive groups. These changes were more exaggerated compared to controls. All the patients were indicative of a sympathetic surge in the presence of withdrawal vagal activity before syncope and a sympathetic inhibition with a vagal predominance at the syncopal stage by the frequency-domain analysis of HRV. With the measurements of DC, a decreased vagal tone before syncope stage and a vagal activation at the syncopal stage were observed. The vagal tone was higher in subjects showing cardioinhibitory responses at the syncopal stage. DC may provide an alternative method to understand the autonomic profile of VVS patients. 展开更多
关键词 vasovagal syncope deceleration capacity heart rate variability head-up tilt-table testing
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Six Minute Walk Test to assess functional capacity in chronic liver disease patients 被引量:6
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作者 Hatem F Alameri Faisal M Sanai +4 位作者 Manal Al Dukhayil Nahla A Azzam Khalid A Al-Swat Ahmad S Hersi Ayman A Abdo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第29期3996-4001,共6页
AIM: To examine the utility of Six Minute Walk Test (6MWT) in patients with chronic liver disease (CLD). METHODS: Two hundred and fifty subjects between the ages of 18 and 80 (mean 47) years performed 6MWT and the Six... AIM: To examine the utility of Six Minute Walk Test (6MWT) in patients with chronic liver disease (CLD). METHODS: Two hundred and fifty subjects between the ages of 18 and 80 (mean 47) years performed 6MWT and the Six Minute Walk Distance (6MWD) was measured. RESULTS: The subjects were categorized into four groups. Group A (n = 45) healthy subjects (control); group B (n = 49) chronic hepatitis B patients; group C (n = 54) chronic hepatitis C patients; group D (n = 98) liver cirrhosis patients. The four groups differed in terms of 6MWDs (P < 0.001). The longest distance walked was 421 ± 47 m by group A, then group B (390 ± 53 m), group C (357 ± 72 m) and group D (306 ± 111 m). The 6MWD correlated with age (r = -0.482, P < 0.01), hemoglobin (r = +0.373, P < 0.001) and albumin (r = +0.311, P < 0.001) levels. The Child-Pugh classification was negatively correlated with the 6MWD in cirrhosis (group D) patients (r = -0.328, P < 0.01). At the end of a 12 mo follow-up period, 15 of the 98 cirrhosis patients had died from disease complications. The 6MWD for the surviving cirrhotic patients was longer than for non-survivors (317 ± 101 vs 245 ± 145 m, P = 0.021; 95% CI 11-132). The 6MWD was found to be an independent predictor of survival (P = 0.024). CONCLUSION: 6MWT is a useful tool for assessing physical function in CLD patients. We suggest that 6MWD may serve as a prognostic indicator in patients with liver cirrhosis. 展开更多
关键词 Six Minute Walk test Chronic liver disease Functional capacity
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Regressive approach for predicting bearing capacity of bored piles from cone penetration test data 被引量:3
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作者 Iyad S. Alkroosh Mohammad Bahadori +1 位作者 Hamid Nikraz Alireza Bahadori 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第5期584-592,共9页
In this study, th e least sq u are su p p o rt v ecto r m achine (LSSVM) alg o rith m w as applied to predicting th ebearing capacity o f b ored piles e m b ed d ed in sand an d m ixed soils. Pile g eo m etry an d c... In this study, th e least sq u are su p p o rt v ecto r m achine (LSSVM) alg o rith m w as applied to predicting th ebearing capacity o f b ored piles e m b ed d ed in sand an d m ixed soils. Pile g eo m etry an d cone p e n e tra tio nte s t (CPT) resu lts w ere used as in p u t variables for pred ictio n o f pile bearin g capacity. The d ata u se d w erecollected from th e existing litera tu re an d consisted o f 50 case records. The application o f LSSVM w ascarried o u t by dividing th e d ata into th re e se ts: a train in g se t for learning th e pro b lem an d obtain in g arelationship b e tw e e n in p u t variables an d pile bearin g capacity, and testin g an d validation sets forevaluation o f th e predictive an d g en eralization ability o f th e o b tain ed relationship. The predictions o f pilebearing capacity by LSSVM w ere evaluated by com paring w ith ex p erim en tal d ata an d w ith th o se bytrad itio n al CPT-based m eth o d s and th e gene ex pression pro g ram m in g (GEP) m odel. It w as found th a t th eLSSVM perform s w ell w ith coefficient o f d eterm in atio n , m ean, an d sta n d ard dev iatio n equivalent to 0.99,1.03, an d 0.08, respectively, for th e testin g set, an d 1, 1.04, an d 0.11, respectively, for th e v alidation set. Thelow values o f th e calculated m ean squared e rro r an d m ean ab so lu te e rro r indicated th a t th e LSSVM w asaccurate in p redicting th e pile bearing capacity. The results o f com parison also show ed th a t th e p roposedalg o rith m p red icted th e pile bearin g capacity m ore accurately th a n th e trad itio n al m eth o d s including th eGEP m odel. 展开更多
关键词 Bored piles Cone penetration test(CPT) Bearing capacity Least square support vector machine(LSSVM) TRAINING VALIDATION
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Uplift Pile Test in Rocks and Its Bearing Capacity 被引量:2
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作者 吴兴序 于志强 袁文忠 《Journal of Southwest Jiaotong University(English Edition)》 2002年第1期84-89,共6页
This paper reports in situ tension test and laboratory model test for large diameter, manually digging anchorage piles in the 2nd Luzhou Changjiang Bridge. Tension behavior, uplift bearing capacity and influenc... This paper reports in situ tension test and laboratory model test for large diameter, manually digging anchorage piles in the 2nd Luzhou Changjiang Bridge. Tension behavior, uplift bearing capacity and influence of rock characteristics on bearing capacity are discussed. Proposes are presented with respect to issues related to the construction and design of uplift piles. 展开更多
关键词 uplift pile ROCK bearing capacity test
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Analysis of Capacity Decay, Impedance, and Heat Generation of Lithium-ionBatteries Experiencing Multiple Simultaneous Abuse Conditions
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作者 Casey Jones Meghana Sudarshan Vikas Tomar 《Energy Engineering》 EI 2023年第12期2721-2740,共20页
Abuse of Lithium-ion batteries,both physical and electrochemical,can lead to significantly reduced operational capabilities.In some instances,abuse can cause catastrophic failure,including thermal runaway,combustion,a... Abuse of Lithium-ion batteries,both physical and electrochemical,can lead to significantly reduced operational capabilities.In some instances,abuse can cause catastrophic failure,including thermal runaway,combustion,and explosion.Many different test standards that include abuse conditions have been developed,but these generally consider only one condition at a time and only provide go/no-go criteria.In this work,different types of cell abuse are implemented concurrently to determine the extent to which simultaneous abuse conditions aggravate cell degradation and failure.Vibrational loading is chosen to be the consistent type of physical abuse,and the first group of cells is cycled at different vibrational frequencies.The next group of cells is cycled at the same frequencies,with multiple charge pulses occurring during each discharge.The final group of cells is cycled at the same frequencies,with a partial nail puncture occurring near the beginning of cycling.The results show that abusing cells with vibrational loading or vibrational loading with current pulses does not cause a significant decrease in operational capabilities while abusing cells with vibrational loading and a nail puncture drastically reduces operational capabilities.The cells with vibration only experience an increase in internal resistance by a factor of 1.09–1.26,the cells with vibration and current pulses experience an increase in internal resistance by a factor of 1.16–1.23,and all cells from each group reach their rated lifetime of 500 cycles without reaching their end-of-life capacity.However,the cells with vibration and nail puncture experience an increase in internal resistance by a factor of 6.83–22.1,and each cell reaches its end-of-life capacity within 50 cycles.Overall,the results show that testing multiple abuse conditions simultaneously provides a better representation of the extreme limitations of cell operation and should be considered for inclusion in reference test standards. 展开更多
关键词 Lithium-ion batteries dynamic abuse testing electrochemical impedance spectroscopy incremental capacity analysis thermal profile analysis
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Lateral load-carrying capacity analyses of composite shear walls with double steel plates and filled concrete with binding bars 被引量:1
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作者 周德源 刘凌飞 朱立猛 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第8期2083-2091,共9页
A method is developed to predict the lateral load-carrying capacity of composite shear walls with double steel plates and filled concrete with binding bars(SCBs). Nonlinear finite element models of SCBs were establish... A method is developed to predict the lateral load-carrying capacity of composite shear walls with double steel plates and filled concrete with binding bars(SCBs). Nonlinear finite element models of SCBs were established by using the finite element tool, Abaqus. Tie constraints were used to connect the binding bars and the steel plates. Surface-to-surface contact provided by the Abaqus was used to simulate the interaction between the steel plate and the core concrete. The established models could predict the lateral load-carrying capacity of SCBs with a reasonable degree of accuracy. A calculation method was developed by superposition principle to predict the lateral load-carrying capacity of SCBs for the engineering application. The concrete confined by steel plates and binding bars is under multi-axial compression; therefore, its shear strength was calculated by using the Guo-Wang concrete failure criterion. The shear strength of the steel plates of SCBs was calculated by using the von Mises yielding criterion without considering buckling. Results of the developed method are in good agreement with the testing and finite element results. 展开更多
关键词 composite shear wall double steel plate binding bar lateral load-carrying capacity nonlinear finite element analysis
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Shape design of the reinforcement for bending load-carrying capacity of under-matched butt joint under four-point bending load 被引量:1
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作者 王佳杰 杨建国 +3 位作者 张敬强 董志波 方洪渊 刚铁 《China Welding》 EI CAS 2012年第3期50-54,共5页
To improve the bending load-carrying capacity ( BLCC) of under-matched butt joint under four-point bending load in the elastic stage, the shape design of the reinforcement is studied based on the theoretics of mecha... To improve the bending load-carrying capacity ( BLCC) of under-matched butt joint under four-point bending load in the elastic stage, the shape design of the reinforcement is studied based on the theoretics of mechanics of materials. The concept, criterion, realization condition and design proposal of equal bending load-carrying capacity (EBLCC) are put forward. The theoretical analysis results have been verified by the finite element method. The simulation results are coincident basically with the ones of theoretical analysis. The research results show that the shape design of the reinforcement of EBLCC can improve BLCC of under-matched butt joint and the unilateral-side type reinforcement can replace double-side symmetry 展开更多
关键词 under-matched joint equal bending load-carrying capacity shape design of the reinforcement finite elementmethod
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Using a GIS to Assessment the Load-Carrying Capacity of Soil Case of Berhoum Area, Hodna Basin, (Eastern Algeria) 被引量:1
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作者 Amar Guettouche Farid Kaoua 《Journal of Geographic Information System》 2013年第5期492-497,共6页
The concept of load-carrying capacity of the soil can be evaluated by two main components: permissible stress and permissible depth;and therefore, running it begins its assessment that allows an outline of exploitatio... The concept of load-carrying capacity of the soil can be evaluated by two main components: permissible stress and permissible depth;and therefore, running it begins its assessment that allows an outline of exploitation. Nevertheless, the assessment of the load-carrying capacity made the object of several works of research and many models, based on the multi-criteria analysis, have been established. This work examines the contribution of GIS approach to assessment load-carrying capacity of the soil. This one has been finished in two practicums: 1) Assessment of the capacity of soil by a multi-criteria approach, using the Weighted Sum Model (WSM);2) It brought to use the GIS approach to evaluate and spatialize degree of soil bearing stresses resulting from the buildings, as well as load distribution. The method has been applied to the Berhoum area of Hodna Basin, in eastern Algeria, where each is characterized by its various natural properties and density of equipment. Final results are better in the classification of the degree of load-carrying capacity possible in each site. This results in allowing exploiters to program their optimal designs for the rational management of the area. 展开更多
关键词 load-carrying capacity WSM GIS Berhoum Hodna Basin’s Algeria
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Boundary slippage for generating hydrodynamic load-carrying capacity
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作者 张勇斌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第9期1155-1164,共10页
Boundary slippage is used to generate the load-carrying capacity of the hydrodynamic contact between two parallel plane surfaces. In the fluid inlet zone, the fluidcontact interfacial shear strength on a stationary su... Boundary slippage is used to generate the load-carrying capacity of the hydrodynamic contact between two parallel plane surfaces. In the fluid inlet zone, the fluidcontact interfacial shear strength on a stationary surface is set at low to generate boundary slippage there, while in the fluid outlet zone the fluid-contact interfacial shear strength on the stationary surface is set at high enough to prevent the occurrence of boundary slippage. The fluid-contact interfacial shear strength on the entire moving surface is set at high enough to prevent boundary slippage on the moving surface. These hydrodynamic contact configurations are analyzed to generate the pronounced load-carrying capacity. The optimum ratio of the outlet zone width to the inlet zone width for the maximum load-carrying capacity of the whole contact is found to be 0.5. 展开更多
关键词 hydrodynamic contact load-carrying capacity boundary slippage
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A Discusion on Limited Load-Carrying Capacity of Rectangular Plates
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作者 Li Changchun Shi Depei Wang Bocheng Associate Professor, Department of Naval Architecture and Ocean Engineering, Jiao Tong University,Shanghai 200030Engineer, Shangsha Shipyard, Shangsha 410013 《China Ocean Engineering》 SCIE EI 1996年第4期401-408,共8页
The elastic-plastic method is often used in designing the inner flat bulkhead plates of submarines, and the upper structure of ships and drilling platforms. Such bulkhead plates can bear the load only once. For the im... The elastic-plastic method is often used in designing the inner flat bulkhead plates of submarines, and the upper structure of ships and drilling platforms. Such bulkhead plates can bear the load only once. For the improvement of the load-carrying capacity or the reduction of the weight of plates, the yield line analytical method is employed in this paper to design the bulkhead plate to improve economy and increase the effiective load. Besides, a further sutdy of this method has been made theoretically and experimentally, and the data of the limited load-carrying capacity of the plate have been obtained. Furthermore, the safety coefficients for such a method are presented, which can be used as reference for related departments and staffs. 展开更多
关键词 elastic-plastic design limited load-carrying capacity yield line analytical method safety coefficient
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Model tests on uplift capacity of double-belled pile influenced by distance between bells
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作者 SUN Tao CUI Xin-zhuang +5 位作者 SUN Yan-feng HAN Ruo-nan MA Rui-jin YANG Jun-jie WANG Yi-lin CHANG Yu-jun 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第5期1630-1640,共11页
To optimize the distance between the bells in pile design,this paper reports a series of small scale tests on the uplift capacity of double belled piles embedded in dry dense sand considering different bell space rati... To optimize the distance between the bells in pile design,this paper reports a series of small scale tests on the uplift capacity of double belled piles embedded in dry dense sand considering different bell space ratios.Finite element modelling is also performed to evaluate the range of soil failure around the piles during pile uplift displacement.Test results show that when bell space ratio is 6 or 8,the uplift capacity reaches the peak value.The upper bell bears more load than the lower one for the piles with bell space ratio less than 6,while the lower bell bears more load than the upper one for the piles with bell space ratio larger than 8. 展开更多
关键词 doubled-belled pile optimized distance uplift bearing capacity model test sand foundation
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The Clinical Role of Changes of Maximum Expiratory Flow at 25%and 50%of Vital Capacity before and after Bronchodilator Reversibility Test in Diagnosing Asthma
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作者 Xu-xuc GUO Xiao-fan LIU +7 位作者 Ai-ling WANG Qian-hui CHEN Shuo CHEN Ni-shan DENG Rui-yun LI Xu-hong DING Su ping HU Han-xiang NIE 《Current Medical Science》 SCIE CAS 2020年第4期677-682,共6页
Summary:Changes of maximum expiratory flow at 25%and 50%of vital capacity(MEF2s and MEFso,respectively),and predominant parameters indicating small airways function in asthmatics before and after bronchodilator(BD)rev... Summary:Changes of maximum expiratory flow at 25%and 50%of vital capacity(MEF2s and MEFso,respectively),and predominant parameters indicating small airways function in asthmatics before and after bronchodilator(BD)reversibility test have been less interpreted.Our study aimed to investigate the clinical role of changes of MEF2s and MEFso before and after BD reversibility test in diagnosing asthma.Forced expiratory volume in the first second(FEV),MEF2s,and MEFso were measured before and after BD reversibility test in 207 asthmatic patients using standard process.Forty healthy individuals were enrolled as controls.Receiver operating characteristic(ROC)curve was used to assess the diagnostic accuracy of reversibility of MEF2s and MEFgo before and after BD reversibility test(OMEF 2s%and AMEF so%,respectively)in diagnosing asthma.Among these functional criteria,AMEF2;%and 0MEFs%≥25%performed the best diagnostic performance.The sensitivity,specificity,and accuracy of AMEF 25%≥25%as an objcctive diagnostic test for asthma were 63.29%,87.50%,and 67.21%,and of AMEFs0%≥25%were 79.23%,85.00%,and 80.16%,respectively.The area under the ROC curve of the indicators was 0.8203 and 0.9104,respectively.By contrast,an increase in FEV≥12%and 200 mL demonstrated a sensitivity of 62.32%,specificity of 82.50%,and accuracy of 65.59%in diagnosing asthma.The changes of MEF2s and MEFso before and after BD reversibility test may be of additional value in the clinical diagnosis of asthma,with cutoff values of 25%being the most. 展开更多
关键词 ASTHMA bronchodilator reversibility test maximum expiratory flow at 25%of vital capacity maximum expiratory flow at 50%of vital capacity
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Effect of Fine Content on the Bearing Capacity of Replaced Sand Gravely Subgrad-Field Test
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作者 Mohamed Nabil EL Siragy 《Journal of Civil Engineering and Architecture》 2019年第11期715-721,共7页
The compacted soil replacement procedure has been widely used worldwide for overcoming the unfavorable actions of some problematic soils,such as expansive,collapsing soils and ground fill.Compaction of the replacement... The compacted soil replacement procedure has been widely used worldwide for overcoming the unfavorable actions of some problematic soils,such as expansive,collapsing soils and ground fill.Compaction of the replacement soil is necessary for stabilizing such layer for improving its performance.In this study,gravelly-sand soil,which consists of gravel,sand and fines,is widely used as replacement soil in the field.The effect of fines content on possibly achieved density of such soil is experimentally investigated.A series of laboratory compaction and plate loading tests were carried out on the replaced soil at different fine contents of 0,5,8,10,12 and 15%.The results showed that,the supporting capacity of a replacement soil increases with the increase of its dry density.Therefore,the density of the replacement layer is the major factor controlling its behavior under the effect if external stresses.Compacted sand and gravelly sand are preferred materials when used for soil replacement.They tend to have better engineering properties,if they are placed according to the standard specifications.Another experimental stage of the effect of fines on the bearing capacity of circular footings on gravelly-sand with different percentages of fines was performed.It was found that a fine content of 10%gives the highest dry density,if the soil is compacted according to modified proctor specifications and with the addition of fines,the footing settlement increases and the ultimate bearing carrying capacity decreases. 展开更多
关键词 REPLACEMENT soil FINE content plate load test SETTLEMENT and BEARING capacity
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California Bearing Ratio Test on the Bearing Capacity of a Foundation in Unsaturated Soil
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作者 Reine Chancelvie Dimi Eboukou Durell Esperance Ndinga Manguet 《Journal of Geoscience and Environment Protection》 2022年第6期12-25,共14页
The value of the California bearing ratio (CBR) test is an index making it possible to evaluate the load of the foundation soil and the resistance of the pavement materials. The California Bearing Ratio (CBR) of unsat... The value of the California bearing ratio (CBR) test is an index making it possible to evaluate the load of the foundation soil and the resistance of the pavement materials. The California Bearing Ratio (CBR) of unsaturated soils is particularly related to their quality. The mechanism affecting the bearing capacity, in the case of California Bearing Ratio (CBR), has been studied as a transformation of red clay for the backfill. In this study, the effect of compaction energy on compaction characteristics and California Bearing Ratio (CBR) values was investigated. The relationship between the CBR value (California Ratio Ratio) and the degree of compaction is characterized by a gradual evolution of unsaturated soils with different water contents. The results show that the compaction degree and California Bearing Ratio (CBR) value of the soil in the cold region are insufficient, but the bearing capacity of the compacted soil after immersion under the maximum dry density can still meet the filling requirements. The red clays tested are considered useful as bedding in areas of unsaturated soils. 展开更多
关键词 Compacted Soil CBR testing Bearing capacity COLONIES
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Discussion on bearing capacity of soft rock ground based on in-situ load test
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作者 Gao Wenhua Zhu Jianqun Huang Ziyong Liu Dong 《Engineering Sciences》 EI 2010年第4期37-41,共5页
The suitability of five methods was discussed here,taking the typical results from in-situ load test of Renshou Mansion and Caifu Plaza in Yueyang City for example.It shows that bearing capacity can be obtained by the... The suitability of five methods was discussed here,taking the typical results from in-situ load test of Renshou Mansion and Caifu Plaza in Yueyang City for example.It shows that bearing capacity can be obtained by the proportion load and limit load from p-s curve with the first and the second point of contraflexure easily.It is recommended that the accurate value of bearing capacity can be obtained by hyperbola fitting method and minimum curvature radius method theoretically.The rebound method is clear in principle,in which the elastoplasticity characteristic is thought about.Out of consideration for the unsteadiness and unobviousness of bearing capacity from relative settlement method,it can be only adopted as reference.So bearing capacity of soft rock ground should be determined by weathering condition of soft rock and curve type. 展开更多
关键词 rock mechanics soft rock bearing capacity of ground in-situ load test of rock ground characteristic curve
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