Statistical Methodology Commons^™

Numerical Simulation Of Mechanical Performance For Anti‑Collision Steel Pontoon, Han Xiaolei, Wang Bo, Li Weidong

Journal of China & Foreign Highway

Anti-collision steel pontoo n has good plasticity and energy absorption properties in ship-bridge collision.To explore the factors affecting the anti-collision performance of the anti-collision pontoon,a collision model composed of ship,anti-collision pontoon,and pier system was built based on finite element software Ansys/LS-DYNA.The collision mechanism and process were numerically simulated,and the effects of connection type between anti-collision pontoon and pier,peak angle of pontoon,and anti-collision pontoon stiffness on the collision force of the pier were investigated.The three-stage division method of collision force curve was put forward.The analysis shows that the fixed inwall of the anti-collision steel pontoon and connection to the pier surface …

Deformation And Damage Characteristics Of A Newly Operated Tunnel Caused By Above Foundation Pit Construction, Liu Jiqiang, Zhu Min, Hao Kun, Chen Dengwei, Chen Xiangsheng

Journal of China & Foreign Highway

The construction of foundation pits in granite residual soil layers is prone to causing upheaval deformation and structural damage in shield tunnels below.Based on the engineering case of a newly operated metro tunnel collinear with the above long-distance deep foundation pit in Shenzhen,a three-dimensional finite element model was established to investigate the variation law of the heave and horizontal convergence of the shield tunnel caused by the deep foundation pit excavation.The correlation between the longitudinal stress of the lining structure and the damage was analyzed.The results indicate that the tunnel deformation caused by foundation pit unloading is primarily vertical heave,accompanied …

Dynamic Response Rules Of Adjacent Buildings To Blasting Construction In Shallow Buried Tunnels, Luo Yanping, Li Jigang, Wang Sheng, Zeng Bin, Lai Jinxing, Feng Zhihua, Qiu Junling

Journal of China & Foreign Highway

In order to study the dynamic response rule of overlying buildings during blasting construction in shallow buried tunnels,the urban tunnel in Fuzhou was taken as the engineering background,and the on-site monitoring and Ansys/LS-DYNA simulation were used to analyze the structural response of overlying buildings.The monitoring results show that the building is most obviously affected by blasting in the vertical direction and has an obvious elevation amplification effect,and the maximum vibration velocity is 2.45 cm/s.The vibration velocity in all directions gradually decreases and tends to be stable with the increase in explosion center distance and decays rapidly when the explosion center …

Deflection Basin Characteristics Of Distressed Roads Under Moving Load, Cai Yingchun, Xie Shenjian

Journal of China & Foreign Highway

The deflection basins of roads under moving load imply the distress information of subgrade and pavement.Therefore,how to use the information of deflection basins under moving load to rapidly test road distresses non-destructively has received much attention.In this paper,the finite element model of semi-rigid base asphalt pavement was established.By setting different types and degrees of finite element distress models,the continuous changes of surface deflection basins under moving load were analyzed.The results show that when the load moves to the distress area,the center deflection value of surface deflection basins in each distress model will become larger.When transverse cracks appear in the pavement …

Curing Mechanism And Influencing Factors Of Cement Mixing Piles Reinforcing Peat Soil, Feng Rongxian, Zhong Gaibing, Liu Liang, Liang Jianyuan, Gu Meixiang

Journal of China & Foreign Highway

The cement mixing pile is used to reinforce the deep peat soil foundation in Malaysia's east coast railway construction.The key in this project is to determine the cement mix proportion and additives.Considering the high organic matter content and strong environmental acidity of coastal peat soil,physical and mechanical tests of peat soil and laboratory uniaxial compression tests of cement soil under different mix proportions and influencing factors were conducted.Test results show that the mean compressive strength decreases by 0.35 MPa with the increase in cement-water from 0.5 to 0.9.Adding mineral powder gives a relatively poor curing effect while adding fly ash …

Safety Of Optimized Concrete Median Barrier Without Planting Soil, Zhong Chunyao, Ma Qing, Li Yangfan, Gong Shuai, Liu Siyuan, Yan Shuming

Journal of China & Foreign Highway

In order to study the safety of optimized concrete median barrier without planting soil,the technology combining computer simulation,sled test,and full-scale impact test of real vehicles was adopted for analysis and verification.In addition,a scheme was proposed to improve the anti-overturning ability of the barrier without planting soil by strengthening the supporting block,and the scheme of setting a 20 cm-high supporting block between the barrier walls was optimized.The safety of the barrier scheme was evaluated by taking the most unfavorable large truck as an example.The results show that the protection level of the optimized concrete median barrier without planting soil is SAm, …

Aided Design Method And Application Of Rutting Prevention And Maintenance In Asphalt Pavement Based On Digital Holographic 3d Detection, Wang Jingfei, Wang Wang, Xu Xinquan, Huang Zhijian, Ti Jing, Yao Yanru

Journal of China & Foreign Highway

As one of the common diseases of asphalt pavement,rutting has significant impacts on the service life and traffic safety of the pavement.Mild rutting in asphalt pavement during preventive maintenance can lead to increased use of maintenance materials due to rutting deformation.Accurately calculating the amount of materials needed to fill rutting in maintenance designs is of great significance for ensuring maintenance quality and efficiency.Based on the requirements of maintenance engineering,this paper analyzed the problems in maintenance designs that use traditional methods and the data they generate for rutting detection.A design method was proposed for rutting prevention and maintenance in asphalt pavement,assisted …

Extreme Value Statistics Analysis Of Process Defects In Additive Manufacturing Materials, Ayorinde E. Olatunde, Kristen Hernandez, Austin Ngo, Arafath Nihar, Thomas G. Ciardi, Rachel Yamamoto, Pawan K. Tripathi, Roger H. French, John J. Lewandowski, Anirban Mondal

Faculty Scholarship

Fatigue and fracture studies focused on process defects that occur in Additive Manufacturing (AM) materials have shown that defect populations possess features which are better measured with extreme value statistics (EVS). In AM alloys, defect occurrences increase with material volume. This situation facilitates the need to model process defects in the path of fatigue crack growth with suitable statistical tools, such as EVS, which is more cost-effective when compared to destructive experiments. The application of EVS on defect space features helps determine the difference in defects present on fracture surfaces. As the fatigue quality of any material depends on its …

A Contingency Table Alternative To Poisson Regression In Comparing The Frequency Distributions Of Two Populations, Sandra Tay

Dissertations

When testing the conditional independence between a binary outcome and a binary treatment indicator, conditioned on a categorical variable with k levels, typically represented by a K × 2 frequency table, researchers often turn to Poisson regression and the Cochran-Mantel-Haenszel (CMH) test. However, a common challenge encountered in these analyses is the presence of treatment effect heterogeneity. Introducing an interaction term between treatment indicators and effect modifiers in log-linear regression offers potential solutions, yet the equidispersion assumption of Poisson regression remains problematic. On the other hand, the CMH test assumes similar treatment effects across all strata, disregarding potential variations among …

Alternative Adjacency Matrices And Spatial Analysis, Jaeseong Hwang

Dissertations

Spatial analysis is essential for comprehending the spatial distribution of diseases and various phenomena across geographic regions. This study investigates the utilization of alternative adjacency matrices in spatial analysis, with a specific focus on implementing Poisson regression models. This study intricately explores the methodology behind constructing alternative weight matrices, specifying weight matrices, and comparing the performance of Poisson models using five different weight matrices.

The popular Poisson model model is described, and five different definitions of weight matrices are defined, which are the following: binary weight matrix, inverse distance weight matrix using Euclidean distance, Graph distance matrix, Path matrix, and …

Value Added Tax Rate Variation, Import Demand And Sectoral Output In Nigeria, Joshua K. Nomkuha, Aondoawase Asooso, Philip T. Abachi

CBN Journal of Applied Statistics (JAS)

This study employs computable general equilibrium (CGE) model to estimate the effect of increase in value added tax (VAT), from 5 per cent to 7.5 per cent, on import demand and sectoral output in Nigeria. The study uses 2020 as the base year for the data analysis. The results show that increase in VAT affects import demand negatively, based on import penetration ratios, with mixed effect across six sectors. The implication of the result is that the VAT policy discourage consumption of foreign products, and constitute excess burden to consumers of such products in Nigeria. The results further reveal that …

Trade Liberalization, Non-Oil Export And Economic Growth In Nigeria, Jerome T. Andohol, Terhemen Tarzoor, Dennis T. Nomor

CBN Journal of Applied Statistics (JAS)

The study examines the impact of trade liberalization and non-oil exports on economic growth in Nigeria from 1986 to 2021. The study utilizes an autoregressive distributed lag model and found the combined effect of trade liberalization and non-oil exports to be positive and statistical significant. While trade liberalization alone may have negative consequences, its synergy with a robust non-oil export can drive sustainable economic growth. The study recommends that strategies to enhance non-oil exports should be encouraged to support the effectiveness of trade liberalization in promoting growth.

The Effectiveness Of Monetary Policy Transmission In Nigeria: Evidence From The Monetary Policy Rate And The Cash Reserve Ratio, Abdulrahman A. Nadani, Auwal Isah

CBN Journal of Applied Statistics (JAS)

This paper investigates the effectiveness of the Monetary Policy Rate (MPR) and Cash Reserve Ratio (CRR) as policy instruments in Nigeria. A structural VAR model is employed to simulate two distinct models measuring shocks from the MPR and the CRR using monthly data from January 2006 to December 2023. Findings show that contractionary monetary policy impulses using MPR and the CRR contract output and credit to the private sector, inflation remains largely positive in the two models, known as the “price puzzle”, but the puzzle is more persistent in the MPR equation. Moreover, shock to MPR strongly influences short-term interest …

Stock Market Volatility In The United Kingdom: Simulating Post-Covid-19 Recovery, Bala A. Dahiru, Mohammed Shuaibu, Najibullah Hassanov

CBN Journal of Applied Statistics (JAS)

This paper investigates the time it would take for the FTSE-100 index to reach its post-COVID-19 peak. The paper utilises an exponential generalised autoregressive conditional heteroscedasticity (EGARCH) model that accounts for leverage effect and asymmetries. The preferred models amongst competing variants was the Autoregressive Moving Average (ARMA)-EGARCH(2,1) specification and was used to predict daily FTSE-100 data from 5th January 2000 to 21st June 2024. The empirical exercise showed that the COVID-19-induced financial crisis negatively affected the United Kingdom’s stock market performance. The results show that the FTSE100 index could reach its post-pandemic peak around 27th August, 2024 (two months after …

Reasonable Construction Method For Grade Ⅳ Surrounding Rock In Single‑Hole Four‑Lane Super‑Span Highway Tunnel, Li Heyin, Gao Jingming, Li Yanfeng, Xun Wenjie, Dong Fangfang, Zhang Jiangang

Journal of China & Foreign Highway

In order to study the reasonable constr uction method of super-span highway tunnels，the Xinghuacun No.1 tunnel included in the reconstruction and expansion project of the Xiaocaohu –Urumqi section of the Lianyungang –Khorgos Expressway in Xinjiang was studied.The numerical simulation method was used to analyze the deformation and stress of the supporting structure of the Grade tisurrounding rock in the super-span highway tunnel constructed by the center diaphragm （CD） method，the upper-bench CD method，and the three-bench and seven-step excavation method.Under the premise that the deformation and the stress of the supporting structure met the design requirements，the advantages and disadvantages of each construction …

Intelligent Bridge Lifecycl E Maintenance System Based On Long‑Term Inspection, Ye Zhiwei, Zhang Jiaxin, Tan Haishan, Fan Lei, He Wen, Dong You, Wu Wanglin

Journal of China & Foreign Highway

The current bridge maintenance sy stem in China primarily relies on bridge inspection data to prioritize the state of bridges and allocate a limited budget accordingly.This strategy focuses on repairing bridges with low performance，concentrating on restorative maintenance but ignoring preventive maintenance.In view of the total lifecycle cost，the repair-oriented method may require a lower initial investment but leads to significant resource consumption in the mid to late stages.Based on existing highway bridge maintenance systems，an intelligent maintenance system relying on Chinese standards and bridge inspection data and combining repair and prevention was developed.The system model mainly consisted of two modules：the bridge performance …

Mechanical And Deformation Characteristics Of Piles In Coastal Soft Soil Areas Considering Softening Effect, Wang Fei, Yan Yu, Jiao Lidong, Shen Fengqi, Chen Lu, Liu Jianhua

Journal of China & Foreign Highway

In order to discuss the mechanical and deformation behavior of piles in coastal soft soil areas under horizontal load，the corresponding simplified mechanical model was established according to the loading characteristics of piles in coastal soft soil areas.Secondly，the softening effect of coastal soft soil was considered to modify the existing p-y curve model.On this basis，the differential equation of pile deflection in coastal soft soil areas was derived，and its internal force and displacement were solved by the transfer matrix method.A nonlinear calculation method of piles in coastal soft soil areas considering the softening effect was obtained.Finally，the influence of softening parameters，pile diameter，and elastic …

Experimental Study On Fracture Performance Of Emulsified Asphalt Cold Recycled Mixture, Chu Chenfeng, Deng Jun, Zhou Chen, Wang Zi ’Ang, Kuang Ao, Liu Hongfu

Journal of China & Foreign Highway

Cracking in emulsified asphalt cold recycled pavements is one of the main constraints on their large-scale application in road engineering.To study the fracture performance indicators of cold recycled asphalt mixture and the improvement measures of crack resistance performance，this study investigated three types of mixtures：ordinary emulsified asphalt，basalt fiber，and styrene-butadiene rubber （SBR） modified emulsified asphalt.This study conducted a four-point bending strength test on notched beams，and acoustic emission tests of the beam with prefabricated cracks were carried out to evaluate the fracture performance of three different emulsified asphalt cold recycled mixtures in road engineering.The evaluation criteria included strain energy release rate，stress intensity factor，energy …

Experiment On Strength And Deformation Characteristics Of Marine Silt Cement Soil And Their Relationship, Deng Wu, Liu Weizheng, Chen Tie, Ge Mengyuan

Journal of China & Foreign Highway

In order to study the compre ssive，flexural，and shear strength and deformation characteristics of marine silt cement soil，a series of laboratory mix ratio tests were carried out，so as to test the changes in unconfined compressive strength fcu，flexural strength ff，normalized shear strength τqg，normalized principal stress difference （σ1‒σ3）/σ3，and compression modulus Es under different dosage of curing agents，curing ages，and cement-to-lime ratios.In addition，the correlation between different parameters was investigated.The results show that the performance of the improved samples with cement and lime is 2%‒17% higher than that with cement alone under the same dosage.The strength of cement soil is proportional to the dosage and age …

Study On Compression Characteristics Of Solidified Mud‑Sand Mixed Fillers Considering Particle Breakage, Han Chao, Yu Yuezhong, Bai Bin, Xu Zhihao, Zhang Xianmeng, Liu Yinying, Kong Shuoying

Journal of China & Foreign Highway

The mixed filler of solidified mud and sand provides an ideal solution for the resourceful disposal of wasted engineering mud，and the compression characteristics of filling engineering are closely related to the strength characteristics and particle breakage characteristics of mixed fillers.This study conducted large size compression tests on mixed fillers with different particle gradations and established a discrete element method （DEM） model that incorporated particle breakage for the side-limited compression tests of solidified mud-sand mixed fillers.The changes in the compression modulus of the mixed fillers and the amount of solidified soil particle breakage during compaction were investigated.The study placed a special …