Other Civil and Environmental Engineering Commons^™

Sustainable – Low-Cost - Upgrade Of Activated Sludge Process For Nitrogen And Phosphorus (N&P) Removal From Wastewater, Abanoub N. Basta

Theses and Dissertations

Many municipal wastewater treatment plants (WWTPs) in developing countries were designed primarily for organic matter and suspended solids removal and therefore face increasing difficulty in meeting modern nitrogen (N) and phosphorus (P) discharge requirements. Conventional biological nutrient removal upgrades commonly require additional reactor volume, recirculation systems, aeration energy, and capital investment. Accordingly, sustainable retrofit strategies that improve nutrient removal within existing treatment footprints are increasingly needed, particularly in water-scarce and land-constrained regions.

This study investigated the integration of water hyacinth (Eichhornia crassipes) into the aeration stage of an activated sludge process as a hybrid nature-based enhancement for nitrogen and phosphorus …

From Disaster To Resilience: Developing Smart Settlements In The Himalayas, Keshav Bhattarai, Ambika P. Adhikari

Himalayan Research Papers Archive

Nepal’s catastrophic 26 August 2026 Bhote Koshi–Trishuli flood should be understood not only as a humanitarian tragedy but also as a potentially major turning point in updating national settlement and reconstruction policy. Engineers and scientists have described the floods as a glacier–bedrock collapse that triggered an ice-rock avalanche and debris flow. As per the live updates on September 7, 2026, the total death toll was 1,355, and 4,996 people were missing (The Hindu, 2026). Indian and Nepali rescuers worked urgently to locate and rescue people buried under hydropower tunnels, buildings, mud, and landslide debris.

UN News reported on September 3, …

A Framework For Automated Quantity Extraction From .Ifc Models And Normalized Bid Comparison, Asmaa Mohamed Farouk

Theses and Dissertations

Accurate bid comparison remains a major challenge in construction tendering due to

differences in Bill of Quantities formats, item naming conventions, and pricing methods across

contractor submissions. These variations require time-consuming manual work and often lead to

subjective decisions. This research presents a computational framework that uses Building

Information Modeling through the .ifc file format, combined with text analysis techniques for

automated bid normalization.

The developed system uses a dual-component approach. Phase 1 extracts quantities from .ifc

model files using 3D geometric calculations, automated element classification. Phase 2 uses text

mining with a domain-specific dictionary of construction terms to interpret …

Research Status And Prospects Of Monitoring Technology For Large-Span Cable-Stayed Bridges Based On Machine Learning, Liu Guoliang, Liu Guokun, Yan Donghuang, Wang Wenxi, Wang Qishun

Journal of China & Foreign Highway

Machine learning and intelligent optimization algorithms have been increasingly applied to construction and health monitoring of long-span cable-stayed bridges. Based on the construction history of cable-stayed bridges both domestically and internationally, an overview of the origin and development process of cable-stayed bridges was provided. Firstly, from the perspective of the entire life cycle of bridges, bridge monitoring was divided into construction period monitoring and operation period monitoring. The applications of mainstream construction monitoring methods in large cable-stayed bridge projects were elaborated, and the specific composition of bridge health monitoring systems was clarified. Secondly, the basic principles of several machine learning …

A Technoeconomic And Lifecycle Analysis Of Catalytic Non-Thermal Plasma Steam Methane Reforming For Renewable Hydrogen Production, Gustav M. King

Master's Theses

When produced with sufficiently low life-cycle emissions, hydrogen may support low-carbon, dispatchable electricity generation to realize statewide renewable energy regulatory objectives. This thesis develops a screening-level electrothermochemical process model of catalytic non-thermal plasma steam methane reforming (CNTP-SMR) and integrates it with techno-economic and life-cycle assessments. Biogas and natural gas fed CNTP-SMR scenarios are compared with conventional steam methane reforming to evaluate hydrogen production cost, global warming potential, and the effects of key operating parameters. Under the baseline assumptions, CNTP-SMR generated hydrogen at a higher levelized cost (baseline of $3.86/kg H₂ and a range of $3.68 to $4.11) when compared …

A Machine-Learning-Based Systematic Framework For Modeling Compression And Recompression Indices For Florida Soils, Michael Morales

Doctoral Dissertations and Master's Theses

This thesis develops a machine-learning framework for estimating the compression index and the recompression index of Florida soils from routinely measured index properties, and reports two studies that build it. Consolidation settlement design requires both indices, and both are obtained from the incremental-loading oedometer test, which occupies a specimen for one to two weeks; the index tests that accompany it are complete within hours. Empirical correlations have filled that interval since the 1950s, but their coefficients are calibrated on specific soil populations and transfer poorly between regions. The first study analyzes 376 consolidation tests compiled for the Florida Department of …

Study On Deformation Characteristics Of Kaolin Under Dry-Wet And Freeze-Thaw Cycles, Yang Shang, Xiao Dingyuan

Journal of China & Foreign Highway

In seasonally frozen areas, surface soil is subjected to prolonged and drastic fluctuations in temperature and humidity, causing excessive deformation and resulting in engineering issues such as subgrade settlement and building deformation. The deformation characteristics of kaolin in seasonally frozen areas under the combined influence of freeze-thaw and dry-wet cycles were studied. Through a self-designed experimental setup, experiments with interleaved dry-wet and freeze-thaw cycles were conducted on compacted specimens, and wetting-freezing-thawing-drying cycle experiments were performed to explore the swelling-shrinkage deformation characteristics of kaolin under the combined action of different freeze-thaw and dry-wet cycles. The results indicate that intermittent freeze-thaw cycles …

Material Point Method Simulation Of Soil Landslide Considering Interface Friction Effect, Zuo Zhipeng, Hu Shengliang, Li Maowen, Tong Chenxi, Li Haichao

Journal of China & Foreign Highway

During the high-speed and long-runout sliding failure process of large landslides, severe friction and heat generation in the sliding zone induce an interface friction effect between the debris flow and the bedrock, influencing the final accumulation morphology of the landslide. In this paper, a two-dimensional landslide model of the Yangbaodi landslide in Shenzhen was established using the material point method. A contact algorithm was introduced through a multi-background grid method to conduct numerical simulations on the initiation, sliding, and accumulation processes of the landslide. The results show that after initiation, the landslide moves over a long distance in a flow-like …

Influence Of Geocell Technical Parameters On Bearing Characteristics Of Highway Subgrades In Oasis Areas, Zhu Chunsheng, Shu Xingyu, Lu Huiyu, Yang Xiaohua

Journal of China & Foreign Highway

To study the effects of technical parameters, such as geocell specifications and laying types, on the bearing capacity and deformation of highway subgrades in oasis flood irrigation areas, the shear properties of plain soil and geocell-reinforced layers with different specifications were studied through large-scale direct shear tests. Based on indoor compression tests and field load tests, numerical simulation parameters, such as the deformation modulus of different foundation soil layers, were calibrated. A numerical model of the geocell-reinforced highway subgrade was established using, and the effects of geocell specifications and laying types on the vertical settlement of the subgrade, the displacement …

Stratified Multi-Well Pumping Tests And Back-Analysis Of Hydraulic Conductivity In Ultra-Deep Circular Foundation Pits, Luo Renkun, Wang Jie

Journal of China & Foreign Highway

Dewatering prior to foundation pit excavation is a critical measure to prevent engineering hazards such as slope instability at the pit top, seepage around the pit, and bottom heave. As a key parameter in dewatering design, hydraulic conductivity directly influences the risk control in foundation pit engineering. Based on the east anchor foundation pit project of the Shiziyang Passageway, single-well pumping tests and stratified multi-well pumping tests were conducted. The water level variations in the internal dewatering wells and the external observation wells were monitored in stages. Accordingly, a finite difference numerical model for the pumping tests was established. The …

Study On Effects Of Phase Change Materials On Thermal Erosion Resistance Of Airport Pavement, Li Ping, Li Yunlong, Zheng Zhipeng, Wang Zhijian, Yi Chengxi

Journal of China & Foreign Highway

To investigate the effect of phase change materials (PCMs ) on improving the thermal erosion resistance of airport pavements and to provide recommendations for selecting optimal PCMs to obtain airport pavements with longer service lives, three PCMs, PCM-G- 98 (A), LB- 2 (B), and TH-HC- 120 (C), were purchased based on literature summaries and market research. Based on microscopic test results and the actual preparation conditions of modified asphalt, PCMs A and B were selected. Subsequently, based on a self-made high-content SBS modified asphalt (S), four groups of composite modified asphalts (S-A- 5, S-A- 10, S-B- 5, and S-B- 10) …

Research On Mechanical Properties And Particle Breakage Of Construction Solid Waste Concrete Under Cyclic Loading, Li Xuejian, Song Yang, Dong Chenxi, Li Shengkai, Li Wangyuan

Journal of China & Foreign Highway

To investigate the mechanical properties and particle breakage effect of construction solid waste, a series of static and dynamic direct shear tests were carried out using a dynamic interface shear tester. Different coarse particle contents (40%, 50%, and 60%), amplitudes (45 kPa, 60 kPa, and 75 kPa), and frequencies (0.5 Hz, 1 Hz, and 2 Hz) were used as variables, and the variation rules of shear stress‒shear displacement curves, shear strength parameters, and particle breakage under three normal stresses (50 kPa, 100 kPa, and 150 kPa) were analyzed. The results indicate that under the same initial normal stress, with the …

Study On Influence Of Elastic Modulus Of Fiber On Compaction Characteristics Of Asphalt Mixtures, Zou Zexi, Luo Kaiyan, Lin Zhiming, Qiu Xiang, Lu Xudong, Yao Xiaoyang, Wang Yaolong

Journal of China & Foreign Highway

To investigate the influence mechanism of fiber incorporation on the compaction characteristics of asphalt mixtures, six types of typical road fibers (polyester fiber, polyacrylonitrile fiber, aramid fiber, basalt fiber, polypropylene fiber, and polyvinyl alcohol fiber) were selected in this paper, and gyratory compaction tests were conducted based on AC- 20 graded mixtures. The compaction coefficient (a larger compaction coefficient indicates easier compaction) was used as the core evaluation index. The results indicate that the elastic modulus of the fiber is the key influencing factor. When the fiber modulus is 50% lower than the aggregate modulus (such as polyester fiber and …

Angularity Evaluation Of Coarse Aggregates Based On Local Feature Extraction Of Point Clouds, Ma Quanzhuo, Feng Ponan, Feng Zezhong, Lei Mingyu, Wang Zhenfeng, Li Jiange

Journal of China & Foreign Highway

The morphological characteristics of coarse aggregates significantly affect the mechanical properties of asphalt mixtures and thus directly influence their road performance and durability. This paper aims to innovatively propose an evaluation method for the angularity of coarse aggregates. A three-dimensional (3D) scanner was used to acquire the surface profile information of coarse aggregates, and local angularity features were extracted through point cloud data analysis. Subsequently, a comprehensive 3D angularity evaluation index for coarse aggregates (A3D) was proposed by combining local normal vectors and curvature characteristics. The results indicate that A3D can be more accurately and independently used for angularity evaluation. …

Study On Mechanical Properties Of Ultra-High Performance Concrete With Granite Manufactured Sand After Heating And Cooling Treatment, Li Gang, Zhou Feilong, Lu Qiuju, Du Kun, Liu Kai

Journal of China & Foreign Highway

Due to the frequent occurrence of building fires, the mechanical properties of concrete, as the most widely used construction material, are severely challenged under high temperatures. To explore the effect of granite manufactured sand content on the performance of ultra-high performance concrete (UHPC) after heating and cooling treatment, three types of UHPC specimens with different manufactured sand contents (0, 50%, and 100%) were prepared in this study. Then, the effects of manufactured sand content, heating temperature, and cooling regime on the P-wave velocity and uniaxial compressive strength of UHPC were obtained through experiments. The results indicate that the P-wave velocity …

Characteristic Analysis Of Detection Profiles For Internal Moisture Content Of Asphalt Pavements Based On Ground Penetrating Radar, Yang Li, He Pingping, Liu Weizhen, Fu An

Journal of China & Foreign Highway

As a novel non-destructive testing method for roads, ground penetrating radar (GPR) can effectively prevent road water damage by regularly detecting the internal moisture condition of roads. However, when the moisture data of GPR are analyzed, the moisture conditions obtained by relying solely on the analysis of a single profile characteristic may be misjudged. To improve the accuracy and reliability of GPR in detecting the internal moisture content of pavements, focus was placed on the time-frequency domain analysis of GPR moisture content detection profiles in this paper. Simulation tests were conducted, and the influencing factors and results of moisture detection …

Optimization Design And Experimental Study On Strength Of Ternary Industrial Solid Waste Mixtures, Yang Shu, Ai Yi, Sheng Shanwang, Li Chuangmin

Journal of China & Foreign Highway

This paper aims to explore whether fly ash, lithium slag, and slag powder (ternary industrial solid wastes) can effectively replace cement as cementitious materials for interlocking large-particle crushed stone bases. A uniform design table U9(94) was used to design the test scheme for the mixing ratios of ternary industrial solid waste mixtures; the correlation between the mortar strength and the ternary industrial solid waste mixtures was analyzed by Pearson correlation; with the help of the mathematical statistical software SPSS 26.0, mathematical models for the flexural strength and compressive strength of the ternary industrial solid waste mixture mortar specimens were established. …

Research On Mechanical Properties Of Concrete At High Temperatures Based On Machine Learning, Liu Junhua, Liu Bin, Cao Haifeng, Liu Zhiguang, Li Zhiyong

Journal of China & Foreign Highway

Structural safety is directly affected by the mechanical properties of concrete at high temperatures. Firstly, based on the existing compression and tension test data of concrete at high temperatures, the Abaqus finite element software was adopted for numerical simulation reproduction, and the reliability of the simulation method was verified. Secondly, by simulating the uniaxial tension-compression and confining pressure tests of normal concrete with different strength grades under high temperatures of 20‒800 ℃, the influence rules of temperature on the compressive strength, splitting tensile strength, elastic modulus, and stress ‒ strain relationship of concrete were elucidated. Finally, based on three commonly …

Research On Dic Monitoring Of Dynamic Deflection And Damage Identification Method For Small And Medium-Span Bridges, Wang Yong, Li Derui, Tang Haotian, Yan Xingfei, Cheng Bin

Journal of China & Foreign Highway

A large number of built small and medium-span bridges in China are facing the problem of increasingly degrading structural performance. Therefore, it is of great significance to carry out lightweight intelligent monitoring and realize damage identification and early warning, so as to ensure the safe operation of these bridges. For typical small and medium-span simply supported beam bridges, a damage analysis method based on measured dynamic deflection data was established by combining the influence line theory and mechanical constitutive equations. Furthermore, based on the high-precision monitoring algorithm and instruments of digital image correlation (DIC), the real-time dynamic deflection data of …

Calculation Of Tensile Force For Cable-Stayed Buckling Bracket Combined With Temporary Tie Rod Structure Of V-Shaped Pier, Zhao Xiaolu, Yang Guang, Liu Junle, Qiu Zhiwei, Meng Lingxin, Peng Weibing

Journal of China & Foreign Highway

To solve the problem of excessive tensile stress of the cross-section during the cantilever casting process of high piers with inclined legs, a determination method of tensile force based on the linear programming theory and unstressed state control was proposed. Based on the internal force equilibrium method and the principle of influence matrix, the method optimized the tensile force with “stress control as the primary and alignment control as the auxiliary”. The unstressed state control method was adopted for forward iteration, and the effect of tangential displacement between segments was considered to verify the alignment of the inclined legs. Finally, …