Engineering Commons^™

A-Posteriori Estimation Of Random Uncertainty For The Reflection Type Q-Factor Measurements, Darko Kajfez

Engineering Software

No abstract provided.

3d Tunnel Inspection With Photogrammetric And Hybrid Systems, Michael Mett, Heiner Kontrus, Nina Müller, Stefan Eder

Shotcrete for Underground Support XIV

The trend in tunnel assessment is towards comprehensive 3D measurement, either based on high quality digital imagery (photogrammetric systems) or the combination of laser and photo systems (hybrid systems). With digital 3D data, quantification and categorization of damage to the tunnel surface as well as the determination of thickness or volumes of layers (e.g. shotcrete) can performed in a comprehensive, fast and economic way.

The faster such tunnel assessment can be executed on site, the lower are the tunnel block times and environmental impairments related to the building measures. The costs for the operating companies can be significantly reduced as …

Plastic Shrinkage Properties Of Natural Fiber Reinforced Shotcrete, Kyong-Ku Yun, Yoon-Sik Baek, Seung-Yeon Han, Yong-Gon Kim

Shotcrete for Underground Support XIV

Recently, natural hemp fibers have been developed for use in wet or dry mix shotcrete instead of conventional synthetic fibers made from petroleum. Synthetic fibers, which is mainly in polypropylene, has been used for controlling an initial shrinkage cracking in concrete, however, the effect was poor showing a severe plastic shrinkage cracking.

Plastic shrinkage cracking is a nonstructural crack that occurs due to the surface drying of concrete in a plastic condition due to rapid evaporation of bleeding water. The volume reduction due to plastic shrinkage and the resulting tensile stress exceeds the tensile strength of the concrete. In particular, …

Untersammelsdorf Tunnel – Challenges, Special Measures And Use Of Special Shotcrete For Tunneling In Lacustrine Clay, Matthias Beisler, Johannes Benedikt, Sebastian Höser, Hanns Wagner, Klaus Berger

Shotcrete for Underground Support XIV

The 665 m long, twin-track Untersammelsdorf Tunnel is being built in the course of the construction of the Koralmbahn line between Graz and Klagenfurt. The tunnel is located in extremely challenging subsoil conditions consisting of silty to fine sandy lacustrine deposits. The developed tunneling concept provided wide-ranging special underground engineering measures as piling, jet grouting and temporary struts and represents a unique construction method to date. Accordingly, numerous challenges arose in the design phase, which could be verified by carrying out extensive trials and investigations in the preparatory period or for which fallback levels had to be provided for the …

Pumping Shotcrete: Past Knowledge Applied For Modern Shotcrete Mix Design, Marc Jolin

Shotcrete for Underground Support XIV

No Abstract.

Shotcrete Of The Outer Shell And The Sealing System, Dietmar Maehner

Shotcrete for Underground Support XIV

This report deals with the loading of the geomembrane during the construction phase of the inner shell of a tunnel. In a systematic parameter analysis at the institute for underground construction at FH Münster the geomembrane and the geotextile were tested under different realistic conditions. Laboratory testing showed a dependence on the seal support surface of the shotcrete and on the characteristics of the geotextile. The deformations of the membranes due to fresh concrete pressure are significantly smaller than the permitted values in the technical regulations.

Please download the abstract file for full content.

Cgste11 Mediates Cross Tolerance To Multiple Environmental Stressors In Candida Glabrata, Mian Huang, Jibran Khan, Manpreet Kaur, Julian Daniel Torres Vanega, Orlando Andres Aguilar Patiño, Anand Ramasubramanian, Katy Kao

Faculty Publications

Candida glabrata is a human commensal and an opportunistic human fungal pathogen. It is more closely related to the model yeast Saccharomyces cerevisiae than other Candida spp. Compared with S. cerevisiae, C. glabrata exhibits higher innate tolerance to various environmental stressors, including hyperthermal stress. Here we investigate the molecular mechanisms of C. glabrata adaptation to heat stress via adaptive laboratory evolution. We show that all parallel evolved populations readily adapt to hyperthermal challenge (from 47 °C to 50 °C) and exhibit convergence in evolved phenotypes with extensive cross-tolerance to various other environmental stressors such as oxidants, acids, and alcohols. Genome …

Investigations Regarding The Pumping Process Of Wet-Mix Shotcrete Improvement And Upgrading Of Underground Traffic Structures, Johannes Flotzinger, Maria Thumann, Florian Steindl, Florian Mittermayr, Benedikt Lindlar, Wolfgang Kusterle

Shotcrete for Underground Support XIV

Workability is a physical property of fresh concrete, which can’t be described with only one single parameter or measured with one single test method. Pumpability and sprayability plays an important role for wet-mix sprayed concrete. The material must be conveyed through the pipe without changing its properties and mix proportion. The mix should leave the nozzle in a uniform stream intermixed homogeneously with the accelerator.

When concrete is pumped through a pipe, a thin layer of paste is lubricating the wall of the pipe. The interaction of the lubricating layer and the pipe wall is of great importance for pumpability. …

A Practitioner’S Guide To Small Unmanned Aerial Systems For Bridge Inspection, Sattar Dorafshan, Robert J. Thomas, Calvin Coopmans, Marc Maguire

Electrical and Computer Engineering Faculty Publications

Small unmanned aerial system(s) (sUAS) are rapidly emerging as a practical means of performing bridge inspections. Under the right condition, sUAS assisted inspections can be safer, faster, and less costly than manned inspections. Many Departments of Transportation in the United States are in the early stages of adopting this emerging technology. However, definitive guidelines for the selection of equipment for various types of bridge inspections or for the possible challenges during sUAS assisted inspections are absent. Given the large investments of time and capital associated with deploying a sUAS assisted bridge inspection program, a synthesis of authors experiences will be …

Multi-Scale Modeling Of The Lamellar Unit Of Arterial Media, Hozhabr Mozafari, Lulu Wang, Yuguo Lei, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

The heterogeneity of the lamellar unit (LU) of arterial media plays an important role in the biomechanics of artery. Current two-component (fibrous component and a homogenous matrix) constitutive model is inappropriate for capturing the micro-structural variations in the LU, such as contraction/relaxation of vascular smooth muscle cells (VSMCs), fragmentation of the elastin layer, and deposition/disruption of the collagen network. In this work, we developed a representative volume element (RVE) model with detailed micro-configurations, i.e., VSMCs at various phenotypes, collagen fibers, and elastin laminate embedded in the ground substance. The fiber architecture was generated based on its volume fraction and orientations. …

Stability Analysis And Reinforcement Of The Existing Karst Cave Passing Through Yujingshan Tunnel, Junsheng Yang, Yipeng Xie, Chaoyun Zhou, Cong Zhang, Xiong Liang

Shotcrete for Underground Support XIV

High-speed Railway tunneling in karst terrain presents a huge challenge to the engineer including the identification, stability analysis and reinforcement of the karst cavities. The Cheng-Gui high-speed railway tunnel had to pass through the largest karst cave discovered in tunnel construction. To guaranteeing the tunnel construction safety, a series of corresponding prevention and control measures are put forward. To begin with, geological drilling, electromagnetic method and surface electrical resistivity tomography are adopted to detect and delineate the underground karst zone. Based on the detection results, this paper has put forward strategies to make the pre-support of karst cave and the …

Practitioner's Guide To Small Unmanned Aerial Systems For Bridge Inspection, Sattar Dorafshan, Robert J. Thomas, Calvin Coopmans, Marc Maguire

Civil Engineering Faculty Publications

Small unmanned aerial system(s) (sUAS) are rapidly emerging as a practical means of performing bridge inspections. Under the right condition, sUAS assisted inspections can be safer, faster, and less costly than manned inspections. Many Departments of Transportation in the United States are in the early stages of adopting this emerging technology. However, definitive guidelines for the selection of equipment for various types of bridge inspections or for the possible challenges during sUAS assisted inspections are absent. Given the large investments of time and capital associated with deploying a sUAS assisted bridge inspection program, a synthesis of authors experiences will be …

Predicting Agricultural Implement Hydraulic Power Demand Using Synchronized Controller Area Network And Ancillary Sensor Data, Gabriel P. Stoll

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

As agricultural implement designs have progressed in recent years, there has been an increase in hydraulic power demand from the tractor. Current power estimation standards do not accurately estimate hydraulic power demand for implements designed with higher hydraulic power requirements. Several stakeholders, including agricultural producers, tractor and implement manufacturers, and government agencies would benefit from accurate published data on these power requirements.

While an increasing amount of operational data available on the Controller Area Network (CAN) of tractors has assisted researchers in more easily obtaining machinery performance data, hydraulic control valve flow rate and pressure measurements are not currently publically …

The Application Of Gray-Scale Level-Set Method In Segmentation Of Concrete Deck Delamination Using Infrared Images, Chongsheng Cheng, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Conventional nondestructive delamination detection of concrete pavements through thermography is often based on temperature contrasts between delaminated and sound areas. Non-uniform backgrounds caused by the environmental conditions are often challenging for contrast-based methods to robustly differentiate the delaminated areas from the sound areas. Instead of focusing on the temperature contrast, this study proposes a temperature gradient-based level set method (LSM) to detect boundaries for delamination segmentations. A modified edge indicator function is developed to represent the normalized temperature gradient of a thermal image. The experimental study was conducted to evaluate its applicability and stability for boundary detection in terms of …

Effective Fuzzing Framework For The Sleuthkit Tools, Shravya Paruchuri

LSU Master's Theses

The fields of digital forensics and incident response have seen significant growth over the last decade due to the increasing threats faced by organizations and the continued reliance on digital platforms and devices by criminals. In the past, digital investigations were performed manually by expert investigators, but this approach has become no longer viable given the amount of data that must be processed compared to the relatively small number of trained investigators. These resource constraints have led to the development and reliance on automated processing and analysis systems for digital evidence. In this paper, we present our effort to develop …

Source-Separated Urine Nitrification And Ion Accumulation In Sub-Irrigated Planters Using Domestic Wastewater, David A. Forrest

Civil Engineering ETDs

Wastewater reuse is a field at the crux of the food-energy-water nexus. This nexus is a modern attempt at qualifying relationships between resource availability and stewardship, and the choices and needs of market-driven culture. This study aims to develop simple low-tech systems to use domestic wastewater or source-separated urine, treated onsite, for domestic container garden water and nutrient supply. Four experiments were conducted to assess specific aspects of this technology to help develop relevant stages in this reuse chain.

The objective of the first experiment was a proof of concept to assess compatibility of sub-irrigated planters (SIP) with treated domestic …

Optimized Shotcrete Design For Irregular Tunnel Excavation, Gottfried Braun

Shotcrete for Underground Support XIV

No Abstract.

Sika Waterproofing Solutions For Tunnels (Traditional Excavation), Philippe Doriot

Shotcrete for Underground Support XIV

No Abstract.

Steelfibre For High Performance Shotcrete, The Way To More Cost Efficiency, Martin Eberli

Shotcrete for Underground Support XIV

This paper shows the relations between costs and time of high performance products and process optimazing.

Owner and at least contractors are under permanent cost and time pressure. The experiance in the shotcrete pumps and machine are in a high level in case of volume and performance. However looks the contractor for more value engineering too save money and time. The important step is to change the established way and optimazing the process to more efficiency. The ready mix are fast, well applicable and the end result of the concrete is allways in a good or high quality. Steel fibre …

Performance Improvement Of Shotcrete By Polymer Binder Modification, Klaus Bonin

Shotcrete for Underground Support XIV

Tunneling construction engineering cannot exist without sprayed concrete – whether it is in tunneling, mining or equivalent constructions. Underground construction is a vast field and will be of strategic urban importance in the future. On the one hand, many existing tunnels will need in short term repair work or enlargements, while there is huge demand for the construction of new ones.

Polymer-modified sprayed concrete is suitable for the most used wet shotcrete application, but, as it is also common to use dry shotcrete, it’s also possible to be used there.

The used polymer amount depends highly on the requirements, in …

Meaningful Testing Of Fibre Reinforced Shotcrete For Lining Designs, Des Vlietstra, Ralf Winterberg

Shotcrete for Underground Support XIV

The routine use of Fibre Reinforced Shotcrete (FRS) as an integral component of ground support systems is well-established. FRS, employing steel or macro synthetic fibres, is used worldwide in service conditions ranging from low stress friable ground to high stress hard rock, and over a wide range of exposure conditions, often harsh, such as at high temperature, chemically aggressive ground or waters, static stresses and dynamic loadings, etc.

Shotcrete linings require a rotation capacity in order to follow ground movements while the arching effect in the surrounding rock mass develops. The fibre reinforcement within the shotcrete overcomes the brittleness of …

Recent And Future Infrastructure Development In Thailand, Preedee Ngamsantikul

Shotcrete for Underground Support XIV

No Abstract.

Evaluating The Cracking Potential Of Shotcrete, Marc Jolin

Shotcrete for Underground Support XIV

No Abstract.

Design Optimization And Application Of Bolt-Shotcrete Support For East Tianshan Tunnel Project In China, Junsheng Yang, Li Linyi

Shotcrete for Underground Support XIV

Bolt-shotcrete support is a form of support with low cost, convenient for construction, uniform structural stress, which is widely used in international tunnel engineering. In this paper, the 2# inclined shaft of East Tianshan tunnel in China is taken as the research object. The stress characteristics of composite lining support and bolt-shotcrete support are analyzed and compared by FLAC^3D software, and the bolt-shotcrete support scheme suitable for this project is put forward. Based on the principle of orthogonal experiment, the most reasonable shotcrete material proportion is selected, and structural stress and displacement monitoring is carried out during the construction …

High-Dimensional Clustering Method Based On Variant Bat Algorithm, Kou Guang, Guangming Tang, Jiajing He, Hengwei Zhang

Journal of System Simulation

Abstract: With the advent of the era of big data, the information resource is growing rapidly, and the data are becoming high-dimensional. Traditional clustering methods have a good effect for low-dimensional data, but no longer apply to high-dimensional data. On the basis of existing high-dimensional clustering algorithm, a high-dimensional clustering algorithm based on intelligent optimization SSC-BA is proposed. A novel objective function is designed, which integrates the fuzzy weighting within-cluster compactness and the between-cluster separation. A variant bat algorithm is introduced to calculate the weight matrix, giving the new learning rules. Simulation experiments are made for the proposed algorithm, and …

Restoration Of Defaced Serial Numbers Using Lock-In Infrared Thermography (Part I), Ikwulono Unobe, Lisa Lau, John Kalivas, Rene Rodriguez, Andrew D. Sorensen

Civil and Environmental Engineering Faculty Publications

Infrared thermal imaging is an evolving approach useful in non-destructive evaluation of materials for industrial and research purposes. This study investigates the use of this method in combination with multivariate data analysis as an alternative to chemical etching; a destructive method currently used to recover defaced serial numbers stamped in metal. This process involves several unique aspects, each of which works to overcome some pertinent challenges associated with the recovery of defaced serial numbers. Infrared thermal imaging of metal surfaces provides thermal images sensitive to local differences in thermal conductivity of regions of plastic strain existing below a stamped number. …

Restoration Of Defaced Serial Numbers Using Lock-In Infrared Thermography (Part Ii), Ikwulono Unobe, Lisa Lau, John Kalivas, Rene Rodriguez, Andrew D. Sorensen

Civil and Environmental Engineering Faculty Publications

This paper details continuing work on the development of a substantive non-destructive method to recover defaced serial numbers stamped or laser engraved into metallic objects based on lock-in infrared thermography. This method relies on the existence of a local zone of plastic strain created from stamping pressures in mechanically stamped pieces and a heat-affected zone in laser engraved samples, both extending to depths below the visible characters. The grain structure within these zones is dislocated due to the external forces applied. These deformed areas are exposed to the surface when the serial numbers are defaced. Infrared thermography utilises the change …

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• Georgia Engineering Foundation Scholarships
• GDOT and FHWA Fund Traffic Safety Research at Georgia Southern

Using Phenomenography In Engineering Education, Una Beagon

Other resources

A phenomenographic study of academic conceptions of professional skills in engineering programmes in Ireland

Algorithms For Designing Processes Of Electronic Interactive Services, Ozod Radjabov

Bulletin of TUIT: Management and Communication Technologies

Today, the integration of electronic interactive services is based on the correct placement of algorithms to ensure solidarity in information systems, the design stages of information systems based on interactive services and the corresponding events, the implementation of functions in a strict sequence.