Structural Materials Commons^™

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 …

Hdd Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony James Robinson

Datasets

In this study, a thermal-economic analysis was conducted to determine the optimum insulation thickness of retrofitted insulation walls in different regions in Ireland. This was based on the Heating Degree Day method (HDD). This dataset contains optimum insulation thickness, payback period, cost savings and carbon emission for all 25 counties in the Republic of Ireland

Reduction Of Embodied Carbon In Buildings Through Use Of Low Carbon Strategies And Standardization And Enforcement Of Life Cycle Assessment, Bhargavi Sai Sudhakar

Master's Projects and Capstones

The building and construction industry is energy intensive and as of 2021, this industry is responsible for 37% of the total global greenhouse gas emissions. In previous studies of conventional buildings, the operational energy of a building contributed to 80% and the embodied energy contributed to 20% of the total life cycle energy. With increase in policies and standards that focus on reducing the operational energy, low energy and certified green buildings have emerged where the operational energy has considerably reduced. The relative and absolute share of embodied energy in these energy efficient buildings have increased due to excessive use …

Initial Exploration Of Reduced Gyrations For Arkansas Asphalt Mix Designs, Jocie L. Baker

Graduate Theses and Dissertations

The most common distresses in asphalt pavement are cracking and rutting. These distresses plague almost every asphalt roadway in the world. Finding ways to mitigate these distresses will improve the performance of asphalt pavements. One way to combat the premature cracking of asphalt in the field is to ensure there is enough asphalt binder within the mix. This will help the flexibility of the asphalt undergoing large loads and deformation. However, it is widely accepted that mix designs across the country lack the appropriate amount of asphalt binder in their mixes, causing dry mix designs that are subject to cracking …

Crack Control And Bond Performance Of Alternative Coated Reinforcements In Concrete, Sachin Sreedhara

All Dissertations

Concrete cracking in structures is a ubiquitous problem which can lead to the deterioration of the structure. Other than affecting the strength aspect of a structure, cracking impacts the serviceability criteria as well. Although cracking phenomenon in any structure is highly inevitable, it has to be minimized in order to maintain a structure’s life effectively. Cracking in reinforced concrete structures is related to the bond strength developed between the bar and the concrete. It also depends on an ability of the bar to resist the stresses due to shrinkage to minimize the crack. Another important aspect is the resistance offered …

The Living Breakwaters Pdr Efforts: Conceptual Scheduling, Calvin O. Walters Jr.

Publications and Research

On October 29, 2012, Superstorm Sandy caused nearly $19 billion in damages in New York City including 69,000 residential units across the five boroughs. This disaster precipitated a post-disaster-rebuilding (PDR) project including roughly $4.2 billion in a Community Development Block Grant allocated towards PDR projects. A portion of the grant was used to construct a living breakwater in Tottenville, Staten Island, consisting of a resiliency approach to risk reduction through erosion prevention, wave energy attenuation, and enhancement of ecosystems and social resiliency to improve resistance to storms for the community of Tottenville. The ridges of each breakwater are designed with …

Optimizing The Self-Healing Efficiency Of Hydrogel Encapsulated Bacteria In Concrete, Ricardo Hungria

LSU Master's Theses

Calcium carbonate precipitation through microbial means is a promising pathway for concrete self-healing technologies, mainly for its microcrack sealing attributes. The main goal of this project was to study and optimize the crack healing efficiency of hydrogel encapsulated bacteria in concrete. To achieve this purpose, Bacillus pseudiformus was implemented as the bacteria strain at a concentration of 10⁸ cells/ml. This bacterium strain along with yeast extract was combined along with three different mineral precursors corresponding to magnesium acetate, calcium lactate, and sodium lactate. All these three precursors were evaluated at two concentrations (67.76 mM/l and 75 mM/l). For each …

Effects Of Bonding Pressure And Lamina Thickness On Mechanical Properties Of Clt Composed Of Southern Yellow Pine, Cody S. Bates

Theses and Dissertations

This study produced cross-laminated timber panels at a range of four lamina thickness (5/8, 1, 1 1/8, and 1 1/4 inch) and three bonding pressures (50, 125, 200 psi), producing a total of 12 panels for mechanical testing. The goal of this study is to observe how the thickness and pressure trends affect the mechanical properties of CLT. Tests include flatwise bending, flatwise shear, internal-bond, and delamination. Results showed that bending MOE decreases as the panel thickness increases while bonding pressure had no significance. Bending MOR was less significant for the thickness and more significant for pressure compared to the …

Shear Strength Of Concrete Beams Made With Belitic Calcium Sulfoaluminate Cement, Caleb W. Chesnut

Graduate Theses and Dissertations

The need for a cleaner alternative to portland cement (PC) concrete has led to increasing interest in alternatives to PC. Structural properties of most of these alternative cements are still an open research topic. One promising alternative cement is belitic calcium sulfoaluminate (BCSA) cement. The study presented in this paper investigated the shear strength, long term compressive strength, and carbonation in BCSA cement and PC concrete beams. A total of twelve eight-foot long beams were made; eight BCSA cement concrete beams and four PC concrete beams to be tested at various ages depending on cement type. Two beams of each …

Semi Real-Time Detection Of Subsurface Consolidation Defects During Concrete Curing Stage, Chongsheng Cheng, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Subsurface consolidation defect is a common issue in concrete pavement construction, and the hidden defects often require costly repairs after project delivery. Therefore, being able to identify this type of defect during construction will enable contractor to conduct quick repairs to avoid costly post-construction rework. In this paper a semi real-time detection approach using infrared thermography is introduced. The developed approach utilizes the hydration heat during curing time to identify the subsurface voids based on the regional temperature contrast. Experimental studies were conducted using artificial void-defect in different sizes and depths. The thermographic analysis is employed to locate the void-defects …

Frequency Effect On Peak Pressure Coefficients Using The Narrowband Synthesis Random Flow Generator (Nsrfg) Method, Zayuris Del Carmen Atencio Mojica

Graduate Theses and Dissertations

The collapse of the Tacoma Narrows Bridge in Washington state in 1940 due to high wind forces gave structural engineers notice of the importance of understanding the behavior of wind forces on infrastructure. Wind forces play an important role in the design of buildings and other structures. ASCE 7-16 is the manual used for the design of these buildings and other structures throughout the country. These design criteria have been approved based on research projects involving experimental procedures. For the design of wind loads, ASCE 7-16 uses criteria based on wind tunnel (WT) tests. However, since the development of computing …

Assessment Of Carbon Dioxide Emission And Its Impact On High-Rise Mixed-Use Buildings In Egypt, Ahmed Salah Hamza

Theses and Dissertations

With Egypt's vision of 2030 focusing on sustainable development with a true emphasis on Carbon Dioxide (CO₂) emission reduction in the newly built cities and high-rise buildings, efforts are exerted on various levels towards accomplishing the vision’s goals. This is achieved through multiple tools and models associated with aiding the reduction of carbon emissions, yet not a clear one was introduced for the mixed-use buildings in Egypt.

Through this work, a significant gap was identified with respect to high-rise buildings carbon emission assessment in Egypt. This was a main driving force for this work in an attempt to …

Enhancement Of Asphalt Performance By Graphene-Based Bitumen Nanocomposites, Sara Moghtadernejad, Ehsan Barjasteh, Ren Nagata, Haia Malabeh

Mineta Transportation Institute

As the State of California continues to grow, demand for enhanced infrastructure such as roadways and highways escalates. In view of the current average highway lifespan of 15–20 years, the improvement of asphalt binders leads to material sustainability by decreasing required maintenance and increasing the lifespan of roadways. In the present investigation, enhancement of asphalt binder properties was achieved by different methods of mixing varying compositions of graphene nanoparticles with an SBS polymer and asphalt binder. Additionally, experimental evaluation and comparison of the rheological and mechanical properties of each specimen is presented. Graphene nanoparticles have attracted great curiosity in the …

Computational Design Of Nonlinear Stress-Strain Of Isotropic Materials, Askhad M.Polatov, Akhmat M. Ikramov, Daniyarbek Razmukhamedov

Chemical Technology, Control and Management

The article deals with the problems of numerical modeling of nonlinear physical processes of the stress-strain state of structural elements. An elastoplastic medium of a homogeneous solid material is investigated. The results of computational experiments on the study of the process of physically nonlinear deformation of isotropic elements of three-dimensional structures with a system of one- and double-periodic spherical cavities under uniaxial compression are presented. The influence and mutual influence of stress concentrators in the form of spherical cavities, vertically located two cavities and a horizontally located system of two cavities on the deformation of the structure are investigated. Numerical …

Comparing The Environmental Impacts Of Using Mass Timber And Structural Steel, Khang Hoang Nguyen, Steelee Knight Morgan

Construction Management

Although mass timber has seen a gradual rise in demand in the past, there has been a lack of extensive research on the environmental impacts of using mass timber as a primary structural framing material. This paper compares structural steel, and mass timber’s total embodied carbon emissions. Accurate estimates were made using plans and specs for different projects retrieved from semi-structured interviews. The estimates were input through the EC3 Calculator to provide extensive total carbon emissions measurements between each construction material. Using structural steel framing increased the project’s overall environmental impact by roughly 84% compared to using mass timber. The …

Initial Assessment Of Liquefied Scrap Tire Concrete, Abdulkareem Kuaryouti, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

A new approach to incorporate scrap tire material into concrete was investigated, where two reclaimed waste tire components, carbon black and fuel oil, were used to replace a portion of water. The effect of “liquid tire” content to water ratios from 5-40% on an otherwise typical concrete mix were assessed, where compressive and flexural strength, flexural toughness, modulus of elasticity, and several fresh concrete properties were determined. Results were compared to typically expected results of traditional shredded tire mixes with equivalent tire content. It was found that the liquid tire mixes experienced significantly less losses of compressive strength and workability …

Hydraulic Balsa Wood Rising Bridge, Kaitlyn Greenfield

All Undergraduate Projects

What is the solution to allowing tall vessels to navigate past a vehicle bridge that is less than 10 [ft] above the water? To answer this question, a balsa wood bridge was designed, constructed, and tested. The bridge needed to articulate by mechanical means, allow for travel through the bridge, and be able to withstand ample force while the main structure only being constructed of balsa wood and glue. The project was analyzed in sections. These sections include: the bridge structure and its members, the hydraulic lift, and the pins needed for the bridge and hydraulic lift to operate. The …

Laboratory Testing And Mechanistic Analysis Of Treated Subgrade Soils, Hari Kumar Reddy Yarrapureddi

Civil Engineering Theses

Calcium-based stabilizing agents such as cement and lime have been extensively used to improve the engineering properties of base and subgrade layers of pavement systems. Recently, polymers and chemical stabilizers have become popular due to cost efficiency, ease of application, and fast curing times. In this study, California Bearing Ratio (CBR) values of polymer and chemical treated soils were compared with the CBR values of soils treated with conventional stabilizers. Parametric sensitivity analyses was carried out on key parameters including the type of subgrade soil, stabilizing agent, stabilizing agent treatment levels, and moisture conditioning. Additionally, numerical analyses was performed to …