Statistics and Probability Commons^™

Study On Anti‐Scattering Performance Of Asphalt Concrete On Aggregate Scattering Pavement Of Highway, Yang Siyuan, Chen Guiliang

Journal of China & Foreign Highway

Due to the lack of quantitative evaluation methods for aggregate scattering degree of expressway asphalt pavement in China and abroad, according to the disease characteristics of surface layer spalling, this paper adopted the Cantabro standard dispersion test to sample the concrete of the section with aggregate scattering of Huangqunan Expressway (G3) in Zhejiang Province. The dispersion impact damage modes of the mixture with different severity were analyzed, and the anti-dispersion performance of concrete was evaluated by mass loss rate and water absorption rate. The results show that aggregate scattering will reduce the density of the concrete structure at the surface …

Variable Speed Limit Control Method For Highway Under Dense Fog, Sun Jiancheng, Qiao Jiaxing

Journal of China & Foreign Highway

In order to solve the problem of traffic safety on expressways under dense fog and change the original fixed speed limit measures, a variable speed limit control method based on the safe allowable speed was proposed. The speed limit value was calculated based on the regulations in road traffic safety law on the speed under dense fog by considering that the traffic law does not mention the road alignment conditions, road conditions, and other factors, and the monitor data was used to approximate replace the data of individual vehicles for data optimization, and the safe speed and safe distance of …

Design And Experimental Study On Special Spherical Support Of Pingtang Bridge, Tang Zhi, Ma Baihu, Du Bin, Xu Xiangdong, Xia Junyong

Journal of China & Foreign Highway

The vertical bearing capacity of the 16# pier of Pingtang Bridge is 10 000 kN, and the horizontal bearing capacity along the bridge is 12 000 kN, which is 120% of the vertical bearing capacity. The support angle needs to reach the technical parameter requirements of 0.05 rad, which far exceeds the requirements of 10–40% horizontal force of conventional highway supports. According to the specific engineering situation, a new type of support with a large horizontal bearing capacity was designed. Firstly, the finite element model of the support was established to analyze the mechanical properties of the support, and the …

Study On Practical Method Of Safety Assessment For Bridges Under Heavy‐Cargo Transportation, Jiang Xu, Wang Wanfeng, He Zhensheng, Gao Xuefeng

Journal of China & Foreign Highway

In order to meet the requirements of the industry for the high efficiency, safety, and reliability of the traffic safety assessment of heavy-duty vehicles, this paper proposed a method that combined a real-time monitoring system with a finite element method for the traffic safety assessment of heavy-duty vehicles on bridges and verified the method through practical projects. The paper evaluated the bridge’s technical condition level before the heavy-duty vehicle passes and determined the resistance reduction factor considering the bridge’s technical condition level. The finite element analysis model of the bridge was established, and the reliability of the model was verified …

Research On Vibration Reduction Measures Of Short‐Hole Blasting For Pile Group Foundation Of Bridge, Long Lidun, Ji Zhongyan, Li Shaofang, Zhou Xu

Journal of China & Foreign Highway

In the construction of pile hole blasting of group pile foundation of bridges, due to the small clear distance between piles, the blasting vibration will have adverse effects on the wall protection of adjacent pile holes and the poured pile core concrete. Measures thus should be taken to control the seismic wave vibration velocity. In view of the inapplicability of conventional blasting vibration reduction measures such as reducing charge and setting isolation ditch in the construction of pile group foundation of the bridge, this paper proposed vibration reduction measures such as setting isolation holes and using air bags to replace …

Analysis Of Influence Parameters Of Steel Corrugated Plate‐Concrete Composite Arch Culvert, Zhang Haijun

Journal of China & Foreign Highway

In order to explore the parameter effect of a composite arch culvert with corrugated steel plate and concrete, based on the engineering background of a composite arch culvert, the influence rules of four parameters, namely fill height, pipe diameter, wall thickness, and uneven settlement, on the stress and deformation of the arch culvert were analyzed based on the control variable method. The results show that the deformation and stress of the arch culvert are positively correlated with the fill height h and pipe diameter R. When h < 25 m, the deformation and stress increase linearly with the increase in the fill height, and when h > 25 m, the deformation and stress increase in a curve form. When R …

Research And Analysis On Controlled Blasting Demolition Of Continuous Thin‐Walled Box Ribbed Arch Bridge, Ma Shaojun, Chen Huibin, Chai Wendong, Zhang Chunquan, Wang Yuan

Journal of China & Foreign Highway

The 1st bridge of the Jialing River in Pengan County is erected over the Jialing River, a tributary of the Yangtze River. Due to earthquakes and perennial high load operation, the overall technical condition is “Class Ⅴ”, which cannot meet the requirements of the design load grade. This bridge is the longest highway bridge dismantled in Sichuan Province. Its structure is a multi-span continuous thin-walled box ribbed arch bridge. In addition, there are obvious diseases, so the demolition is difficult, and the safety risk is great. For the demolition of the bridge by controlled blasting, numerical simulation, shaped charge cutting …

Study On Parameter Optimization Of Feet‐Lock Anchor Pipes Of Tunnels In Unconsolidated Formation, Tang Heqing, Jiang Xishan, Yang Peng

Journal of China & Foreign Highway

In order to give full play to the supporting role of the feet-lock anchor pipe in the tunnel with unconsolidated formation, it is necessary to obtain the optimal construction parameters of the feet-lock anchor pipe. Based on a tunnel project on the Huaping–Lijiang Expressway in Yunnan Province, this paper conducted numerical simulation and field test analysis. By comparing the arch subsidence and horizontal convergence of the supporting structure when the feet-lock anchor pipe with different parameters was constructed, the paper explored the characteristics and causes of the influence of construction parameters on the feet-lock effect. The results show that the …

Simulation Study On Flame Retardant Effect Of Warm‐Mixed Flame Retardant Pavement In Highway Tunnel

Journal of China & Foreign Highway

In order to obtain the flame retardant effect of the warm-mixed flame retardant asphalt pavement in highway tunnels, based on the finite element method and thermodynamics theory, the thermal analysis module of Ansys finite element software was used to study the flame retardant effect of ordinary asphalt pavement, flame retardant asphalt pavement, and warm-mixed flame retardant asphalt pavement under different fire scales. The maximum temperature of the three types of pavement increased with the increase in the fire scale. Under any fire scale, the flame retardant effect of the warm-mixed flame retardant asphalt pavement was increased by 4.9%–8.5% compared with …

Installation Construction Technology Of Composite Girder Cable‐Stayed Bridge Superstructure In Deep‐Cutting Gorge, Ren Lei, Lu Liang, Dong Zhengliang

Journal of China & Foreign Highway

In view of the installation problems of superimposed beam cable-stayed bridge across the deep canyon, this paper studied the superimposed beam lifting, transport on beam, and superimposed beam installation and proposed three kinds of lifting technology with tower truss crane, beam lifting door crane, and large tower crane, as well as two kinds of installation technology including piecemeal assembly by full rotating deck crane and whole segment assembly truss deck crane. It also made a relative comparative analysis, solving the difficulty in vertical lifting on such bridges and providing a reference for the construction of the same type of cable-stayed …

Experiment Research Of High Pressure Jet Grouting Pile On Ultra‐Shallow Buried Tunnel In Strong Weathered Stratum, Lu Liyang, Liu Huan, Li Pinpin

Journal of China & Foreign Highway

By taking the ultra-shallow buried construction of Xinwu Tunnel in Luoding–Xinyi Expressway in Guangdong Province as the engineering background, the key construction parameters and formation reinforcement effect of high-pressure rotary churning pile in ultra-shallow buried tunnel surrounding rock of fully weathered strata were compared. The results show that: ① slurry pressure, rotary churning speed, and lifting speed have obvious effects on the static load bearing capacity of a single pile. Under the same static load condition, greater slurry pressure indicates a lower cumulative settlement value of a single pile and a smaller increase in cumulative settlement value, and the change …

Study On Anti‐Scattering Performance Of Asphalt Concrete On Aggregate Scattering Pavement Of Highway, Yang Siyuan, Chen Guiliang

Journal of China & Foreign Highway

Due to the lack of quantitative evaluation methods for aggregate scattering degree of expressway asphalt pavement in China and abroad, according to the disease characteristics of surface layer spalling, this paper adopted the Cantabro standard dispersion test to sample the concrete of the section with aggregate scattering of Huangqunan Expressway (G3) in Zhejiang Province. The dispersion impact damage modes of the mixture with different severity were analyzed, and the anti-dispersion performance of concrete was evaluated by mass loss rate and water absorption rate. The results show that aggregate scattering will reduce the density of the concrete structure at the surface …

Variable Speed Limit Control Method For Highway Under Dense Fog, Sun Jiancheng, Qiao Jiaxing

Journal of China & Foreign Highway

In order to solve the problem of traffic safety on expressways under dense fog and change the original fixed speed limit measures, a variable speed limit control method based on the safe allowable speed was proposed. The speed limit value was calculated based on the regulations in road traffic safety law on the speed under dense fog by considering that the traffic law does not mention the road alignment conditions, road conditions, and other factors, and the monitor data was used to approximate replace the data of individual vehicles for data optimization, and the safe speed and safe distance of …

Application Of Digital Image Processing In Cracks Of Concrete Pavement, Gao Fan, He Chunguang, Wang Pengzhang, Qin Yanping, Duo Huaqiong

Journal of China & Foreign Highway

The image obtained by using the traditional crack detection method of concrete pavement has some problems, such as low contrast and high noise, which makes it difficult to meet the requirements of modern road engineering management or non-destructive testing. In order to eliminate the interference in crack images, digital image processing technology was used to improve the image quality through computers. This paper took digital image processing as the core and introduced its development and application in pavement cracks. Based on the research progress and achievements of digital image processing on pavement cracks in recent years, the principles and characteristics …

Design And Experimental Study On Special Spherical Support Of Pingtang Bridge, Tang Zhi, Ma Baihu, Du Bin, Xu Xiangdong, Xia Junyong

Journal of China & Foreign Highway

The vertical bearing capacity of the 16# pier of Pingtang Bridge is 10 000 kN, and the horizontal bearing capacity along the bridge is 12 000 kN, which is 120% of the vertical bearing capacity. The support angle needs to reach the technical parameter requirements of 0.05 rad, which far exceeds the requirements of 10–40% horizontal force of conventional highway supports. According to the specific engineering situation, a new type of support with a large horizontal bearing capacity was designed. Firstly, the finite element model of the support was established to analyze the mechanical properties of the support, and the …

Study On Practical Method Of Safety Assessment For Bridges Under Heavy‐Cargo Transportation, Jiang Xu, Wang Wanfeng, He Zhensheng, Gao Xuefeng

Journal of China & Foreign Highway

In order to meet the requirements of the industry for the high efficiency, safety, and reliability of the traffic safety assessment of heavy-duty vehicles, this paper proposed a method that combined a real-time monitoring system with a finite element method for the traffic safety assessment of heavy-duty vehicles on bridges and verified the method through practical projects. The paper evaluated the bridge’s technical condition level before the heavy-duty vehicle passes and determined the resistance reduction factor considering the bridge’s technical condition level. The finite element analysis model of the bridge was established, and the reliability of the model was verified …

Study On Pavement Performance Of Waterborne Epoxy Emulsified Asphalt And Its Application In Micro‐Surface, Jiang Hai, Liu Dachang

Journal of China & Foreign Highway

In order to improve the pavement performance at micro-surface, waterborne epoxy resin was used to modify the emulsified asphalt, and the compatibility, microstructure, mechanical properties, rheological properties, and pavement performance of mixtures of the modified emulsified asphalt were studied. The storage stability test shows that the epoxy emulsion has good compatibility with emulsified asphalt. With the increase in waterborne epoxy resin content, the modified emulsified asphalt tends to form an epoxy resin-dominated skeleton structure. At the same time, with the increase in waterborne epoxy resin content, the adhesion and mechanical properties of emulsified asphalt and aggregate are significantly improved. At …

Reducing Print Time While Minimizing Loss In Mechanical Properties In Consumer Fdm Parts, Long Le, Mitchel A. Rabsatt, Hamid Eisazadeh, Mona Torabizadeh

Mechanical & Aerospace Engineering Faculty Publications

Fused deposition modeling (FDM), one of various additive manufacturing (AM) technologies, offers a useful and accessible tool for prototyping and manufacturing small volume functional parts. Polylactic acid (PLA) is among the commonly used materials for this process. This study explores the mechanical properties and print time of additively manufactured PLA with consideration to various process parameters. The objective of this study is to optimize the process parameters for the fastest print time possible while minimizing the loss in ultimate strength. Design of experiments (DOE) was employed using a split-plot design with five factors. Analysis of variance (ANOVA) was employed to …

Statistical Study Of The Effect Of Implementing An Airveyor System On The Warpage Of Injection Molded Closures, Charles Wesley Bozarth

Masters Theses & Specialist Projects

Berry Global in Bowling Green, Kentucky produces predominantly polypropylene container closures. One variant, the 83mm lined jar closure, is produced by first being injection molded, placed in work-in-progress (WIP) hold for 24 hours to cool, and then finished through the auxiliary liner operation into a final product. While this process is an effective method to produce a quality large-diameter closure and allows the polypropylene adequate time to cool without warping out of shape, the 24-hour WIP time and the manpower needed to accomplish this can negatively impact several business metrics as well as employee safety.

The purpose of this thesis …

Methods Of Uncertainty Quantification For Physical Parameters, Kellin Rumsey

Mathematics & Statistics ETDs

Uncertainty Quantification (UQ) is an umbrella term referring to a broad class of methods which typically involve the combination of computational modeling, experimental data and expert knowledge to study a physical system. A parameter, in the usual statistical sense, is said to be physical if it has a meaningful interpretation with respect to the physical system. Physical parameters can be viewed as inherent properties of a physical process and have a corresponding true value. Statistical inference for physical parameters is a challenging problem in UQ due to the inadequacy of the computer model. In this thesis, we provide a comprehensive …

Time-Dependent Reliability Framework For Durability Design Of Frp Composites, Rajneesh Kumar Bharil

Graduate Theses, Dissertations, and Problem Reports (ETD)

The life-cycle performance, durability, and aging characteristics of Fiber Reinforced Polymer (FRP or Structural Composites) have been of keen interest to the engineers engaged in the FRP design, construction, and manufacturing. Unlike conventional construction materials such as steel and concrete, the design guidelines to account for the aging of FRP are somewhat scattered or not available in an approved or consistent format. Loss of strength over time or aging of any structural material should be of concern to engineers as the in-service lifespan of many engineering structures is expected to exceed 100 years. Use of durability strength-reduction factors or factors …

Implementation Of Multivariate Artificial Neural Networks Coupled With Genetic Algorithms For The Multi-Objective Property Prediction And Optimization Of Emulsion Polymers, David Chisholm

Master's Theses

Machine learning has been gaining popularity over the past few decades as computers have become more advanced. On a fundamental level, machine learning consists of the use of computerized statistical methods to analyze data and discover trends that may not have been obvious or otherwise observable previously. These trends can then be used to make predictions on new data and explore entirely new design spaces. Methods vary from simple linear regression to highly complex neural networks, but the end goal is similar. The application of these methods to material property prediction and new material discovery has been of high interest …

Waste Management By Waste: Removal Of Acid Dyes From Wastewaters Of Textile Coloration Using Fish Scales, S M Fijul Kabir

LSU Master's Theses

Removal of hazardous acid dyes by economical process using low-cost bio-sorbents from wool industry wastewaters is of a pressing need, since it causes skin and respiratory diseases and disrupts other environmental components. Fish scales (FS), a by-product of fish industry, a type of solid waste, are usually discarded carelessly resulting in pungent odor and environmental burden. In this research, the FS of black drum (Pogonias cromis) were used for the removal of acid dyes (acid red 1 (AR1), acid blue 45 (AB45) and acid yellow 127 (AY126)) from wool industry wastewaters by absorption process with a view to …

A Preliminary Study Of Smithport Plain Bottle Morphology In The Southern Caddo Area, Robert Z. Selden Jr.

CRHR: Archaeology

This study expands upon a previous analysis of the Clarence H. Webb collection, which resulted in the identification of two discrete shapes used in the manufacture of the base and body of Smithport Plain bottles. The sample includes the Smithport Plain bottles from the Webb collection, and four new bottles: two previously repatriated specimens in the Pohler Collection, and two from the Mitchell site (41BW4) to test whether those specimens align morphologically with the Belcher Mound or Smithport Landing specimens. Results indicate significant allometry and a significant difference in Smithport Plain body and base shapes for bottles produced at the …

Self-Similar Random Process And Chaotic Behavior In Serrated Flow Of High Entropy Alloys, Shuying Chen, Liping Yu, Jingli Ren, Xie Xie, Xueping Li, Ying Xu, Guangfeng Zhao, Peizhen Li, Fuqian Yang, Yang Ren, Peter K. Liaw

Chemical and Materials Engineering Faculty Publications

The statistical and dynamic analyses of the serrated-flow behavior in the nanoindentation of a high-entropy alloy, Al_0.5CoCrCuFeNi, at various holding times and temperatures, are performed to reveal the hidden order associated with the seemingly-irregular intermittent flow. Two distinct types of dynamics are identified in the high-entropy alloy, which are based on the chaotic time-series, approximate entropy, fractal dimension, and Hurst exponent. The dynamic plastic behavior at both room temperature and 200 °C exhibits a positive Lyapunov exponent, suggesting that the underlying dynamics is chaotic. The fractal dimension of the indentation depth increases with the increase of temperature, and …

Metals Additive Manufacturing Powder Aging Characterization, Thomas Russell Lovejoy, Nicholas Karl Muetterties, David Takeo Otsu

Mechanical Engineering

The metallic additive manufacturing process known as selective laser melting requires highly spherical, normally distributed powder with diameters in the range of 10 to 50 microns. Previous observations have shown a degradation in powder quality over time, resulting in unwanted characteristics in the final printed parts. 21-6-9 stainless steel powder was used to fabricate test parts, with leftover powder recycled back into the machine. Powder samples and test specimens were characterized to observe changes across build cycles. Few changes were observed in the physical and mechanical properties of the specimens, however, there were indications of chemical changes across cycles. Potential …

Blunt Impact Performance Evaluation Of Helmet Lining Systems For Military And Recreational Use, Jaclyn Siniora, Ryan Taylor, Darren Suey

Industrial Technology and Packaging

With the increasing problem in collegiate athletes experiencing injuries to the brain, different helmet liners where put to the test to see which liner provided athletes the greatest protection under specific conditions.

This senior project evaluates five different liners in football helmets. Each of the helmet liners were tested at three different temperatures: hot, cold, and ambient. Each helmet had seven different impact locations which were put to the test. The project was designed to be used to test ACH military combat liners as well. Due to shipping bottle necks the ACH combat liners have been left to future Cal …