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Investigating The Effects Of Suspended Algal Content, Dissolved Oxygen, And Temperature On A High-Frequency Acoustic Attenuation System In A Controlled Laboratory Environment, Noah Watson

Honors Theses

The Single Frequency Acoustic Attenuation System (SFAAS) has been developed at the National Center for Physical Acoustics (NCPA). This system uses acoustic methods to monitor fine suspended sediment concentration in streams. Site-specific calibrations are necessary for this system, and previous research has indicated that algal concentration or dissolved oxygen concentration of water may affect collected data. Temperature, dissolved oxygen concentration, and fluorescence, used as a proxy for algal concentration, were monitored during this system’s use, and calibrations were derived to account for the effect of each of these variables on acoustic measurements. It has been shown that temperature has a …

Evaluation Of Error Sources In Dynamic Multiple-Input Multiple-Output (Mimo) Tests, Odey Yousef

Civil Engineering ETDs

Dynamic testing of systems is used to characterize the relationship between inputs and outputs using frequency response functions (FRFs). Multiple input and multiple output (MIMO) techniques are crucial for realistic representation. In MIMO tests, environmental conditions are replicated by inverting the FRF matrix for input estimation. Steps include system identification, FRF inversion, input estimation, and input application. Each of these steps are nontrivial and require careful attention. Error sources manifest as error between desired and experimental outputs. Significant efforts to minimize this error exist, yet literature lacks a formal understanding of their origins. This research focuses on 3 of these …

Multi-Physics-Based Modeling Of Cracks In Asphalt Concrete, Md Amanul Hasan

Civil Engineering ETDs

Cracking is the most prevalent distress in an asphalt concrete (AC) pavement, and it leads to structural deterioration and premature failure, thereby costing taxpayers a lot of dollars. Accurately assessing AC's cracking performance is necessary for pavement longevity, yet current methods often fall short. For instance, relying solely on binder creep tests to determine low-temperature grade inadequately predicts the AC pavement's low-temperature cracking problem. Understanding AC's loading rate- and temperature-dependent fracture behavior is crucial for gaining insight into the crack propagation in AC. In the first part of this study, a new physics-based analytical methodology is developed utilizing the bending …

The Use Of Repurposed Whole Textiles To Modify The Mechanical And Hydrogeological Properties Of Green Roof Media And Granular Soils, Angelis Almanzar-Chevalie, Yehya Elfgeeh, Calvin O. Walters Jr.

Publications and Research

This study investigates using repurposed whole textiles to modify the mechanical and hydrogeological properties of lightweight Green Roof media and granular pavement soils.

Green Roof Media Green roofs aim to bring the advantages of suburban agriculture to urban environments while improving energy efficiency and enhancing stormwater management in public, commercial, and residential buildings. Previous studies by City Tech undergraduate research assistants demonstrated significant modification in hydrogeological properties when incorporating textile fabric up to 3% textile by weight (%Tex) at an aspect ratio of 1:1. The effects of mixing repurposed whole textile fiber with Green Roof media is evaluated with regards …

Performance-Based Risk Assessment For Large-Scale Transportation Networks, Anteneh Deriba, David Y. Yang

Student Research Symposium

Efficiently assessing the risk of asset failure due to deterioration or extreme events is crucial for transportation asset management. Traditional methods often lack effectiveness in directly evaluating system performance-based risks, facing challenges like the exponential increase in system states and the emergence of low-probability high-consequence events ("grey swan" events). To address these, this paper introduces a novel performance-based risk assessment approach for large-scale transportation networks, inspired by the Transitional Markov Chain Monte Carlo (TMCMC) method. This method transforms the risk assessment problem into a high-dimensional posterior distribution, with system risk acting as the normalization factor (evidence). It also provides risk-based …

Comparative Life Cycle Assessment Of Hydrogen Production Via Various Pv-Assisted Electrochemical Water Splitting Techniques, Achyuth Ravilla, Ilke Celik

Student Research Symposium

Photoelectrochemical (PEC) and photovoltaic-electrochemical (PV-EC) water-splitting technologies have emerged as cost-effective options for large-scale green hydrogen production in industrial applications. Solar to hydrogen (STH) efficiencies of these technologies have reached up to 20% and several pathways have been explored to drive down the cost of hydrogen using these technologies to less than $2/kg. However, the environmental impact assessment of these technologies for industry-scale deployment has not been explored in previous studies. This study assesses the environmental impacts of PEC and PV-EC technologies by conducting a cradle-to-gate life cycle assessment. The functional unit considered for this assessment is 1 kg of …

Revitalizing Turtle Creek Park, Michael Hardyway, Ethan Harm, Abbey Jacoby, Casey Stephenson

Final Reports in ENST 411: Environmental Community Projects

We current ENST 411 students, Abbey Jacoby, Michael Hardyway, Ethan Harm, and Casey Stephenson have chosen to work with Jim Knight, East Buffalo Township, the Merrill Linn Land and Waterways Conservancy, and many others in an attempt to revitalize Turtle Creek Park for a plethora of reasons. Three of us are majoring in biology, and two are majoring in environmental science, which makes much of the information and techniques relevant in Turtle Creek applicable to our courses of study. This project included heavy hands on work which allowed us students to leave a memorable and impactful influence on the Lewisburg …

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 …

Mechanical Performance Of Uhpc Building Envelope Based On Topological Optimization And Modular Composition, Zhou Zhixuan, Jiang Youbao, Liu Jun, Xiang Yi, Zhou Hao

Journal of China & Foreign Highway

To ensure a safe，aesthetic，and lightweight building envelope，an ultra-high performance concrete （UHPC） building envelope and its node connection mode were proposed based on topological optimization and modular composition.Firstly，the UHPC building envelope was optimized by using the method of minimizing structural compliance subjected to given material volume constraints，and the mechanical performance before and after optimization was compared.The modular design was adopted，and the optimization result of the most unfavorable stress area in the model was taken as the basic configuration unit.Then，UHPC tenon and mortise nodes were proposed，which could be simply assembled into modules.By considering the weak mechanical performance of nodes，the finite element analysis …

Key Techniques For Demolition Of Multi‑Span Continuous Arch Bridge With Concrete‑Filled Steel Tubes, Wan Chengf U, Zeng Wenli

Journal of China & Foreign Highway

Taking the demolition project of Jianhu Bridge as the research background，the demolition of arch bridges with concrete-filled steel tubes under complex conditions was studied.First，the current bridge demolition methods and application status were introduced，and three bridge demolition schemes were put forward according to the difficulties of the bridge demolition.The appropriate demolition scheme for the bridge was selected after comparison，and the sequence of arch bridge demolition was explained.Then，the stress characteristics of the bridge at each construction stage were analyzed，and the theoretical and measured displacement and stress at the most unfavorable stage during demolition were compared.Finally，the influence of material strength and temperature on …

Parameter Sensitivity Analysis Of Single‑Tower Cable‑Stayed Bridge With Mixed Beam, Chen Kongliang, Ye Jianxin, Xu Yufeng, Huang Zhuobin, Guo Fengtao

Journal of China & Foreign Highway

To improve the efficiency of the review simulation model of the bridge monitoring unit and study the influence of different parameters of the single-tower mixed beam cable-stayed bridge on the bridge ’s completed state in the construction process，this paper，taking the cable-stayed bridge of Tongji Road in Foshan with a span of （200+68+46） m as the engineering background，adopted the single control variable method and response surface-Monte Carlo method for sensitivity analysis.Taking the main beam alignment，main tower alignment，main beam stress，and the variation of cable-stayed bridge force as control objectives，this paper studied the influence of the variation of main beam weight，initial tensile force，and …

Design And Installation Technology Of Hanging Basket For Long‑Span Concrete Girder Cable‑Stayed Bridge, Zeng Xianliu, Pang Jianguo, Chen Cheng

Journal of China & Foreign Highway

The main bridge of Zhungeer Yellow River Super Major Bridge is a （160+440+160） m double tower double cable plane full floating system concrete grider cable-stayed bridge.The main beam is a 28.4m wide double box prestressed concrete structure.It was constructed by cantilever pouring with a front fulcrum hanging basket.The maximum weight of the cantilever pouring section is 5 800 kN.To ensure the integral rigidity of the hanging basket，the hanging basket bearing platform adopted the steel box girder structure.The long and large components were connected by high-strength bolts made in sections to facilitate the transportation and installation of the hanging basket.The hanging …

Research On Road Performance Of Carbonaceous Shale Subgrade Filler, Zhang Mengjin, Huang Yafei, Wu Qian, Mao Xuesong, Zhang Jianxun, Chen Xinyi, Wang Yueyue

Journal of China & Foreign Highway

The application of carbonaceous shale for subgrade filling not only alleviates the shortage of subgrade filler in carbonaceous shale distribution areas but also meets the strategic requirements of “resource conservation and saving ” and “green development ” for infrastructure construction in China.However，such rocks are weak and susceptible to weathering and disintegration，and they exhibit significant strength deterioration when exposed to water.To fully apply them，their performance must be comprehensively understood.In this paper，the basic properties of the carbonaceous shale were studied，and filler gradation was designed.The tests on compaction characteristics of the filler and particle crushing characteristics after compaction，RCBR （California bearing ratio ） variation …

Mesoscopic Numerical Simulation Of Concrete Cracking Caused By Nonuniform Corrosion Of Strands, Zeng Tianbao, Chen Hong, Huang Xiaoqi, Tu Ronghui, Dai Lizhao

Journal of China & Foreign Highway

The non-uniform corrosion of spinning strands will induce concrete cracking.A non-uniform expansion model of corrosion products of strands was established，and a mesoscopic numerical model of concrete cracking caused by non-uniform corrosion of strands was built.Concrete was considered as a three-phase composite material composed of mortar matrix，aggregate，and interface layer.The concrete cracking behavior caused by the non-uniform corrosion of strands was simulated by embedding cohesive elements.The rationality of the proposed model was verified by existing experimental data，and the influence of protective layer thickness and aggregate content of concrete on the width of corrosion-induced cracks was discussed.The results show that the proposed non-uniform …

Research And Field Test On Ultra‑Thin Wearing Course Based On Balanced Design Concept, Gu Jianjun, Li Xia, Li Atan, Sun Qiang, Li Jie, Jiang Zhaowei

Journal of China & Foreign Highway

To address the application of an ultra-thin wearing course in expressway asphalt pavement maintenance engineering，the ultra-thin wearing course system based on the balance design concept was systematically studied.In this paper，the action mechanism and application characteristics of modifiers were analyzed，and the proportion design test of the ultra-thin wearing course was designed based on the balance design method.Finally，according to the proportion design test，the optimal proportion of the ultra-thin wearing course material was selected for test road paving.Research shows that the direct-cast high viscosity modifier is convenient for transportation and storage，improves the elastic recovery of asphalt mixtures and reduces permanent deformation.Under the condition …

Experimental Study On Static And Dynamic Mechanical Properties Of Pva Fiber‑Reinforced Coral Concrete, Zhou Jinyi, Long Zhilin, Guo Ruiqi, Kuang Dumin, Cai Yang, Chen Shasha, Chen Jinjie

Journal of China & Foreign Highway

To enhance the mechanical properties of coral concrete，static mechanical tests were conducted at five polyvinyl alcohol fiber volume fractions （0，0.5%，1%，1.5% and 2%）.The impact compression properties were investigated under four strain rates using a split Hopkinson pressure bar with a diameter of 100 mm.The results show that the incorporation of an appropriate number of fibers can significantly improve the static compressive strength and splitting tensile strength of concrete.Dynamic mechanical tests show that coral concrete has an obvious strain rate effect，and the incorporation of fibers can improve the sensitivity of the dynamic reinforcement factor to strain rate，with the reinforcement effect becoming saturated …

Influence Of Warm‑Mixed Flame Retardant Technology On Construction Environment Of Asphalt Pavement In Long Tunnel, Xian Jianglin, Li Yanxiang, Yang Qingyang

Journal of China & Foreign Highway

With the long tunnel as the research object，the variation of volatile organic compound （VOC） volume fraction，CO volume fraction，and illuminance in the construction area of the middle of the tunnel under the conditions of hot mix technology and warm-mixed flame retardant technology was tested respectively，and the influence of warm-mixed flame retardant technology on the construction environment of asphalt pavement in long tunnels was analyzed and evaluated.The results show that when the pavement of a long tunnel adopts hot mix technology，the mass concentration of asphalt fume in the whole operation area is relatively high，and that in some areas exceeds the threshold value.The …

Influence Of Concrete Barrier Slope Parameters On Protective Effect Against Vehicle Collision, Gong Shuai

Journal of China & Foreign Highway

In order to study the influence of concrete barrier slope parameters on the protective effect against vehicle collision，the vehicle models and concrete barrier models were established.The validity of these models was verified using the real vehicle test data.Then，the collision analysis was conducted on the single-slope concrete barrier with different slopes，improved concrete barrier with different slope parameter combinations，and reinforced concrete barrier with anti-climbing function by using the validated models，respectively.The results show that the slope is the key parameter that affects the protective performance of the single-slope barrier，and vehicles cannot be effectively protected if the slope is too small or too large.The …

Evaluation Of Long‑Term Water Stability Of Acidic Diorite Asphalt Mixtures In Different Environments, Cao Zhonglu, Chen Ping, Liu Xuewen, Tan Bo

Journal of China & Foreign Highway

The short-term water stability of acidic diorite asphalt mixtures with acid-alkaline composite aggregates mixed with cement （2% cement instead of mineral powder ），slaked lime （30% slaked lime water for stone immersion ），and anti-spalling agent （modified asphalt with 0.3% anti-spalling agent ） was evaluated by Marshall test of immersion，freeze-thaw splitting test，and rutting test.Then，by repeated freeze-thaw splitting test，repeated freeze-thaw and baking splitting test，and repeated acid-etching freeze-thaw splitting test，the long-term water stability of the treated acidic diorite asphalt mixtures in different environments was tested.The results show that the physical and mechanical properties of acidic diorite meet the specification requirements；the short-term water stability of …

Test And Analysis On Stress And Deformation Of Assembled Geocell Retaining Wall, Kong Yongbo, Li Hao, Zhang Jianwei, Li Junjie, Yang Xiaohua

Journal of China & Foreign Highway

The variable cross-section geocell retaining wall of the Chengdu –Yibin Expressway test road in Sichuan Province of China was studied.First，the construction method of the new-type assembled geocell retaining wall was introduced，and the new-type glass fiber reinforced plastic lightweight panel was used to effectively solve the problem that the panel of the retaining wall is not neat and easy to be damaged.Secondly，the supporting effect of the retaining wall was analyzed by field monitoring.The field monitoring results show that the earth pressure at different parts of the retaining wall is nonlinearly distributed along the height of the retaining wall.The earth pressure at …

Reasearch On Fatigue Failure Law In Tension‑Shear Zone Behind Wheel In Rigid And Flexible Composite Pavement, Cheng Xiaoliang, Deng Fuhao, Wang Yang, Han Leilei, Zhou Wujun

Journal of China & Foreign Highway

In order to study the slippage mechanism of asphalt concrete overlay on continuous reinforced concrete composite pavement （CRCP），the structure of the composite pavement was modeled using the elastic layered system，and the interlayer bonding state of the model was calibrated by the measured data of the road.In the analysis of interlayer mechanical behavior，it was found that when the horizontal force coefficient was 1，there existed a tension-shear zone behind the wheel，which may lead to the failure of this zone prior to the position of the maximum interlayer shear stress.Relevant test data analysis shows that when the horizontal force coefficient is 1，under the …

Experimental Research On Anti-Uv Aging Performance Of Tire Pyrolysis Carbon Black （Tpcb） Modified Asphalt, Yang Wansheng, Yi Shuaibing, Dai Tianle, Li Tiantian, Gan Youwei

Journal of China & Foreign Highway

To investigate the anti-ultraviolet （UV） aging performance of waste tire pyrolysis carbon black （TPCB）-modified asphalt，TPCB-modified asphalt was prepared and subjected to UV aging tests alongside the base asphalt at various intervals.The micro changes and surface roughness of two kinds of asphalt surfaces were studied by atomic force microscopy （AFM）.The behavior changes in ductility，softening point，and penetration of two asphalts before and after UV aging were tested by asphalt performance tests.The results show that the reduction height of TPCB-modified asphalt is smaller than that of base asphalt，and the surface roughness is larger than that of base asphalt at each time.The performance change …

Structure And Material Of Rigid‑Flexible Composite Pavements And Development, Liu Zhaohui, Huang You, Yu Shiqing, Liu Jingyu, Li Sheng, Liu Li, Pan Yu

Journal of China & Foreign Highway

The rigid-flexible composite pavement，as a kind of durable pavement structure，has been widely used for heavy-duty traffic，special geological conditions，bridge tunnel paving，etc.In order to promote the application of durable rigid-flexible composite pavements and clarify the key research issues and development directions，relevant research progress of rigid-flexible composite pavements in China and abroad was reviewed.Based on the structure design theory and construction technology of rigid-flexible composite pavements，the structural mechanical behavior characteristics of rigid-flexible composite pavements were described，and the stress induced by load and temperature of asphalt surface layer and rigid base layer，as well as their interactions were analyzed.The asphalt surface layer on the rigid …

Experimental Study On Double‑Mixture Solidification And Ratio Optimization Of Dredger Fill Sludge, Qin Liang, Chen Zhimin, Lu Yongfei

Journal of China & Foreign Highway

In order to study the optimal r atio of cement and calcium oxide by double-mixture solidification for improving dredger fill sludge，the soil modification results by double-mixture solidification were analyzed based on orthogonal experiments.Finally，the fuzzy comprehensive evaluation method was used to quantitatively optimize each ratio scheme.The results show that：① Under the same addition ratio （addition amount of 1.0%‒4.0%），there is a positive linear correlation between the optimal moisture content and the addition amount，and there is a negative linear correlation between the optimal moisture content and the maximum dry de nsity.Under non-equal addition ratios，the law is not obvious.However，compared to cement，the water-reducing effect of …

Road Performance Of Reclaimed Asphalt Mixture Mixed With Bagasse Fibers And Rubber‑Modified Asphalt, Jiang Xin

Journal of China & Foreign Highway

Given the potential resource value of rec laimed asphalt pavement，waste rubber powder，and bagasse fibers，it is meaningful to develop the cooperative utilization of various solid wastes.This paper studied the microstructure and thermal characteristics of bagasse fibers，carried out the mix design of a reclaimed asphalt mixture with bagasse fibers and rubber-modified asphalt，and evaluated its road performance.At the same time，the test road was paved successfully and observed for a time.The results show that the hollow lumen with multilayer fiber structure in bagasse fibers contributes to absorbing free asphalt in mixtures and enhances the adhesion between bagasse fibers and asphalt.The thermal properties of bagasse …