Capacity Analysis Method Research Articles

Degradation mechanism of limestone and time-varying pile capacity assessment in bank slopes under dynamic erosion of CO2 solution

The dynamic erosion effect of the corrosive medium formed by aqueous solution and CO2 gas on rock will lead to the decline of the mechanical properties of rock and seriously threaten the long-term stability and durability of rock mass in the reservoir area. In this paper, a dynamic erosion test method of CO2 solution on rock mass is proposed to study the deterioration effect of CO2 solution on rock, based on the gas–liquid cycle. A total of 210 limestone samples were tested under various dynamic erosion cycles (0, 5, 10, 15, 20, 25, and 30 cycles). A systematic analysis of key physical properties related to the degradation behavior of rock (Young's modulus, uniaxial compressive strength, tensile strength, shear strength, cohesion, and internal friction angle) was performed. Additionally, the changes in dissipated energy, fractal dimension, and micro-pore evolution during the solution erosion process were examined. The results indicate that with the increase in erosion cycles, the mechanical parameters of the samples gradually decreased, while both the proportion of dissipated energy and the fractal dimension of fragmentation increased nonlinearly by 29.58% and decreased by 9.95%, respectively. The porosity of the samples increased from 0.04% to 6.89%, and their multifractal spectrum gradually shifted to the right, indicating the development of internal pores and decreased microscopic structural stability. Finally, a limit analysis method for time-varying bearing capacity analysis of limestone pile foundation was established to analyze the time-varying evolution characteristics of pile capacity based on the deterioration effect of solution on rock.

Enhancing State of Health Prediction Accuracy in Lithium-Ion Batteries through a Simplified Health Indicator Method

Accurately predicting the state of health (SOH) of lithium-ion batteries is crucial for optimizing battery performance and achieving efficient energy management, especially in electric vehicle applications. However, the existing incremental capacity analysis methods, which are mostly based on curve multi-parameter analysis, still have limitations in terms of computation, prediction accuracy, and adaptability to actual operating conditions. This paper conducts an in-depth analysis of the incremental capacity (IC) curve and proposes a feature parameter based on the area under the IC curve. By incorporating charge and discharge data, a weighted health indicator sequence is constructed and three mathematical models are proposed to link health indicators with cycle number, capacity, and SOH. The feasibility of using impedance as an additional input is also explored, despite the challenges of measurement, revealing its potential applications. Validation of the models with different datasets shows that the proposed method achieves both average relative error and root mean square error within 5%, outperforming other methods in terms of minimizing error and ensuring stability. The results demonstrate that the area-weighted incremental capacity method significantly enhances battery health monitoring accuracy, contributing to the development of sustainable and efficient energy storage systems.

Degradation analysis of lithium-ion batteries under ultrahigh-rate discharge profile

Degradation analysis of lithium-ion batteries under ultrahigh-rate discharge profile

A Coupled NMR and Differential Capacity Study of the Consumption of Electrolyte and Additive Components during the Formation Cycle of Li-Ion Pouch Cells

Understanding the side reactions occurring inside lithium-ion cells remain a significant challenge, presenting opportunities for innovation. In this context, we developed a coupled 1H NMR (nuclear magnetic resonance) and dQ/dV (differential capacity) analysis method aimed at enhancing our understanding of these reactions during the formation cycle. Using deuterated acetonitrile as an extraction solvent, we measured the relative consumption of electrolyte components inside different electrolyte, including in 1.2M LiPF6 EC:EMC 3:7 2% VC and 1.2M LiPF6 EC:EMC 3:7 2% VC + 1% DTD electrolytes at different voltage. Our NMR observations were subsequently compared with electrochemical data to better understand and validate the results. These findings offer valuable insights into lithium-ion cell dynamics and mark a significant step towards the advancement of diagnostic techniques.

Shear resistance test analysis and calculation method of shear capacity of UHPC-NC beam without web reinforcement

In order to study the failure phenomenon and shear resistance performance of UHPC-NC beams without web reinforcement, shear resistance tests were carried out on 15 UHPC-NC beams without web reinforcement. The variation parameters were shear span ratio, web thickness, steel fiber content, and compressive stress level. The load-deflection curve, failure phenomenon and crack development of the test beam are analyzed. The test results show that the joint between the top plate and the bottom plate of UHPC-NC I-beam without web reinforcement is the weakest, and the cracked web is easy to be “cut off” at the joint; The “banding crack area” of web is closely related to the shear span ratio, and the width of ribbon area increases with the increase of shear span ratio. The shear capacity of UHPC-NC I-beam without web reinforcement decreases with the increase of shear-span ratio. The shear capacity increases with the increase of web thickness and compressive stress level. The shear capacity has little relationship with steel fiber content, and the initial stiffness of the structure can be improved by applying prestress. Finally, considering the influence of the top slab compression-shear zone and the bottom slab tension-shear zone on the shear capacity of UHPC-NC prestressed composite beams without web reinforcement, the corresponding calculation method of shear capacity is given based on the modified compression field theory and the idea of sub-item superposition, and the applicability of the calculation method is verified by the test results.

Online two-dimensional filter for anti-interference aging features extraction to accurately predict the battery health

Online two-dimensional filter for anti-interference aging features extraction to accurately predict the battery health

An implicit stabilized node-based smoothed finite element method for ultimate bearing capacity analysis of strip footing

An implicit stabilized node-based smoothed finite element method for ultimate bearing capacity analysis of strip footing

Research on energy storage capacity analysis and short-term load prediction method for new energy high penetration system

The uncertainty of high penetration new energy is strong. After the proportion of electric units is reduced, the flexible resources are suppressed, and the system-level energy storage can effectively relieve the frequency modulation pressure. In this paper, an energy storage capacity analysis method is proposed for new energy high permeability system. The short-term load is predicted by quantile regression analysis, so as to obtain the optimal peak regulation and frequency modulation frequency in operation, so as to further analyze the relationship between new energy permeability, capacity and energy storage power. The results show that the analytical method proposed in this paper can determine the demand capacity of the new energy high permeability system.

Calculation method of deep-water surface conductor bearing capacity based on jetting operation parameters

Calculation method of deep-water surface conductor bearing capacity based on jetting operation parameters

ANALISIS PENGGUNAAN ALAT BERAT TERHADAP WAKTU DAN BIAYA (STUDI KASUS : PROYEK JALAN RAYA BABATBOJONEGORO KM 72-73)

Roads are infrastructure built by the government to facilitate regional development so that they become assets that must be managed and function optimally. The transportation infrastructure and facilities system as a basic infrastructure is a prerequisite for the economic movement of the region, where the supporting system and transportation infrastructure drivers play a major role in the efficiency and effectiveness of regional economic activities. The purpose of this study is to determine the time and cost of using heavy equipment used in Babat-Bojonegoro Highway Project KM 72-73 completion on paving work. 
 This research uses the work capacity analysis method, namely by calculating data to find the working capacity of the heavy equipment used, as a basis for calculating the time and cost required for heavy equipment in the implementation of paving work. 
 From the analysis of the time required by heavy equipment in paving work with a volume of 3612 tons / m3 is 167,5 hours or 24 days. For the total cost of heavy equipment analyzed in paving work amounting to Rp. 405.486.106.

Coupling Dual Nonlinearity of Arch Bridge Bearing Capacity Analysis Method

In order to realistically restore the mechanical properties of the arch bridge under load and damage processes, a coupled dual nonlinear analysis method is established for the arch-bridge load–carrying capacity by considering the effects of bidirectional force transfer and adaptive section stiffness. First, based on the geometric nonlinear theoretical method of bidirectional force transfer, the macroscopic structural deformation of arch ribs under different loading conditions and load levels is preliminarily calculated, including the bending and axial deformation of each section of the arch, which is used to characterize the development of plasticity. According to deformation or strain, the fiber model analysis method is used to determine the true moment–curvature and axial force–curvature development paths of key sections, and then the elastic–plastic flexural and compressive stiffnesses of each section under different deformation states are derived. The elastic–plastic stiffness is substituted back to the geometric nonlinear equations to obtain the deformation and internal force along the arch ribs considering the cross-sectional plasticity. Finally, the above process is cycled until the equivalence condition is satisfied between the structural internal force/deformation and cross-sectional ones. In order to verify the rationality and accuracy of such a coupling method, a model test is carried out on a stiff skeletal concrete suspension chain line arch with a span of 12[Formula: see text]m, whose results match satisfactorily with that of calculated by the coupling dual nonlinearity method. Compared with the method suggested in the code JTG3362-2018, the proposed method can better predict the development of deflection of different arch rib sections, as well as the actual internal force state. The bending moment calculated as per the code is 7–16% larger than the test result at the ultimate capacity state, while the method of this paper is within 5%.

Experimental study on heat transfer performance of high temperature heat pipe under axial non-uniform heat flux

Experimental study on heat transfer performance of high temperature heat pipe under axial non-uniform heat flux

Comparative Analysis of Bearing Capacity of Pile Foundation Using Van Der Ween, Philipponnat, and Meyerhof Methods

Soil has different characteristics so that it becomes a lot of problems in Civil Engineering construction, especially in foundation planning, it must be done carefully and use several methods as a comparison. This research is to compare the three methods of calculating the bearing capacity of bored pile foundations: Van Der Ween, Phillipponnat, and Meyerhof. The selection of an apposite method in bearing capacity analysis is important to confirm the safety of the building structure. The Van Der Ween Method is a more modern and detailed approach compared to the Meyerhof Method, it takes into account the negative impact of the lateral deformation of the pile, which improves the accuracy of its calculation. The Philipponnat Method is a method that combines aspects of both the Meyerhof Method and the Van der Ween Method, it considers load characteristics and soil properties like Meyerhof, while also accounting for lateral deflection of the piles like Van der Ween. The results show that each method has advantages and disadvantages in determining the bearing capacity of bored pile foundations. Analysis revealed factors such as pile diameter, soil depth, and maximum applied load affect the accuracy of the three methods. This research provides important insights for construction planners in selecting a suitable method for bored pile foundation bearing capacity analysis. It is recommended that soil characteristics and pile geometry be considered before selecting the most appropriate calculation method. This research can be extended by considering other methods and conducting validation through experimental analysis.

Analysis Method for Photovoltaic Absorption Capacity of Distribution Network Based on Risk Quantification and Network Reconstruction

The random characteristics of photovoltaic (PV) power will cause changes in node voltage and line power, which is an important factor affecting the photovoltaic absorption capacity of the distribution network (DN). So as to accurately evaluate the impact of photovoltaic randomness on the absorption capacity of DN, an analysis method of photovoltaic absorption capacity of DN is proposed based on risk quantification. Firstly, a photovoltaic absorption capacity evaluation model is proposed based on risk quantification, which considers the randomness of load and PV power and can improve the accuracy of photovoltaic absorption capacity assessment. Secondly, the photovoltaic absorption capacity DN is calculated with the network topology and photovoltaic access capacity of the DN as the optimization variables. The probabilistic power flow is performed by linear power flow, which effectively improves the calculation speed. Finally, the proposed PV absorption capacity analysis method is simulated and analyzed. The simulation results show that the proposed method can effectively take into account the impact of load and photovoltaic randomness and improve the photovoltaic absorption capacity of DN.

A Battery Capacity Estimation Framework Combining Hybrid Deep Neural Network and Regional Capacity Calculation Based on Real-World Operating Data

Efficient battery capacity estimation is of utmost importance for safe and reliable operations of electric vehicles (EVs). This paper proposes a battery capacity estimation framework based on real-world EV operating data collected from forty electric buses of the same model operating in two cities. First, a reference capacity calculation method is presented by combining the Coulomb counting method with the incremental capacity analysis method. Then the impacts of temperature, current, and State-of-Charge on battery degradation are quantitatively analyzed. Using the historical probability distributions as battery health features, a hybrid deep neural network model that combines a convolutional neural network with a fully-connected neural network is proposed for battery capacity estimation. The validation results show that the proposed model outperforms the state-of-the-art methods and reaches a mean absolute percentage error of 2.79 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\%$</tex-math></inline-formula> , while maintaining low computational cost.

Deterministic and Probabilistic Analyses of the Bearing Capacity of Screw Cast in Situ Displacement Piles in Silty Soils as Measured by CPT and SDT

The bearing capacity of screw cast in situ displacement piles is mostly unexplored. There is also insufficient research on piles in silty soils. Therefore, five cone penetration tests (CPT) and one piezocone penetration test (CPTu) using direct methods were utilised to determine the load-bearing capacity of four displacement piles in Estonia. In addition to the CPT sounding data, static-dynamic test (SDT) results were used to analyse the load-beating capacity of the piles. Both deterministic and probabilistic methods were used in the analysis. Characteristic values as a 95% reliable mean and 5% fractile values for sounding parameters, according to the Eurocode 7, were included. Additionally, Monte Carlo simulation was included in the reliability-based design (RBD). The bearing capacities of screw cast in situ displacement piles in silty soils, here based on the CPT and SDT sounding data, were similar. The adaptation of SDT results for the CPT direct methods for pile load-bearing capacity analysis certainly deserves attention and further investigation. For both sounding types, the Eurocode 7 method provided the best results for all piles. The results of pile-bearing capacities in the absolute difference varied within ±11% between the average, RBD and characteristic values.

The future capacity prediction using a hybrid data-driven approach and aging analysis of liquid metal batteries

The future capacity prediction using a hybrid data-driven approach and aging analysis of liquid metal batteries

Kinematic horizontal slice method for uplift capacity analysis of plate anchors in nonhomogeneous soils with a nonlinear failure criterion

Kinematic horizontal slice method for uplift capacity analysis of plate anchors in nonhomogeneous soils with a nonlinear failure criterion

Electric vehicle battery state of health estimation using Incremental Capacity Analysis

Electric vehicle battery state of health estimation using Incremental Capacity Analysis

State of health and remaining useful life prediction of lithium-ion batteries based on a disturbance-free incremental capacity and differential voltage analysis method

State of health and remaining useful life prediction of lithium-ion batteries based on a disturbance-free incremental capacity and differential voltage analysis method