Structural Engineering Commons^™

Characterization And Modeling Of Asphalt Concrete For Dynamic Properties And Performances, A S M A. Rahman

Civil Engineering ETDs

The recently developed mechanistic-empirical pavement design guide (MEPDG, also known as Pavement M-E design method) uses the nationally calibrated, binder viscosity-based dynamic modulus predictive model for the design and analysis of asphalt pavements. In this study, this model is assessed for its appropriateness for asphalt-aggregate mixtures typically used in New Mexico. In essence, this study investigates the predictability issue of complex modulus of New Mexico mixes. A total of 54 Superpave mixes with different aggregate gradations, air voids, and binder grades were collected from the mixing plants and from the pavement construction sites. The loose asphalt mixtures were then compacted, …

Numerical Evaluation Of The Lateral Behavior Of Vertical And Battered Pile Group Foundations Using 3-D Finite Element Modeling, Ahmad Souri

LSU Doctoral Dissertations

The design of pile foundations to resist lateral loads is essential in offshore structures and bridge foundations. The lateral behavior of piles has been studied in the past by experimental investigations coupled with analytical and numerical methods. The problem is complex due to the nonlinearities from soil behavior, gap formation, and pile-soil-pile interaction in pile groups (or the group effect). In this work, the finite element (FE) modeling was used to study the lateral behavior of pile groups. The FE method is robust and allows incorporating the necessary aspects for studying the behavior of pile groups. The nonlinear material behavior …

Seismic Performance Of Steel Helical Piles, Moustafa K. El-Sawy

Electronic Thesis and Dissertation Repository

Recent earthquakes have highlighted the need for safe and efficient construction of earthquake resilient structures. Meanwhile, helical piles are gaining popularity as a foundation for new structures and retrofitting solution for existing deficient foundations due to their immense advantages over conventional driven pile alternatives. In addition, helical pile foundations performed well in recent earthquakes, proving they can be a suitable foundation option in seismic regions. The objective of this thesis is to evaluate the seismic performance of helical piles by conducting full-scale shaking table tests and nonlinear three-dimensional numerical modeling using the computer program ABAQUS/Standard. The experimental setup involved installing …

Soil-Structure Interaction Effects On The Seismic Response Of Low-Rise Eccentrically Braced Frames, Luis Gerardo Buitrago Goyez

Graduate Theses and Dissertations

The importance of soil-structure interaction (SSI) effects on the seismic response of

buildings has been long recognized and has been researched for over 40 years. However, SSI

analysis has only been applied in a few building projects because the fixed base condition is

considered to provide a conservative estimation for the response of buildings under seismic loads.

This assumption of a fixed base condition adopted by practitioners is not always conservative or

cost-effective, especially for rigid buildings over soft soils. Additionally, for the case of ductile

steel frames with eccentric configurations, the influence of SSI on their seismic performance has …

Characterization Of Unknown Bridge Foundations, Saman Rashidyan

Civil Engineering ETDs

The National Bridge Inventory (NBI) recognized 86,133 bridges in the United States have no foundation data on record in 2003. It is evident that an unknown percentage of the 86,133 bridges identified by NBI with missing foundation data could also be highly vulnerable to scouring induced by water flow coupled with erodible soils. Conventional excavation, coring and boring excavations to identify unknown bridge foundation depths and types are deemed to be expensive, destructive, and limited in their application to the unknown foundation problem. Many surface and borehole nondestructive testing (NDT) technologies have been developed for this purpose. Three economical proven …

Effectiveness Of Small Strain Shear Wave Velocity As A Property For Assessing Damage Associated With Alkali-Silica Reaction In Concrete, Dillon K. Self

Civil Engineering Undergraduate Honors Theses

This research paper details the monitoring of expansion and shear wave velocity for fifteen concrete prisms cast in accordance with ASTM C1293 utilizing five mix designs with varying levels of ASR reactivity. Jobe sand and sodium hydroxide pellets were added in various quantities to increase the reactivity of the prisms. Strain measurements of the prisms were taken according to ASTM C129 and the shear wave velocity of the prisms was measured using ASTM C215. These measurements were taken weekly, then monthly for over a year. It was determined that shear wave velocity of the prisms decrease linearly as strain in …

Induced Earthquakes And Public Safety, Lyndsey L. Dickson

Civil Engineering Undergraduate Honors Theses

Like the number of earthquakes felt in Oklahoma, the number of media reports regarding large-magnitude earthquakes in Oklahoma has increased in recent years. News headlines that mention property damage and question who is responsible have sparked heated debated. In this document, a discussion is presented over the responsibility of engineers for the public’s safety in relation to earthquakes. Input from various groups is discussed, the action taken in Oklahoma is outlined, and ethical obligations presented by the American Society of Civil Engineers are considered. The United States Geological Survey (USGS) has reported a major grievance against building-code committees, but many …

Mathematical Model Of The Shell With The Infill For Retaining Structures, Alexander T. Bekker, Nikita Ya. Tsimbelman, Dmitriy A. Potyanikhin, Andrey I. Mamontov, Ömer Bilgin, Tatiana I. Chernova

Ömer Bilgin

A description of finite element model and analysis of a shell with an infill is performed. A large diameter thin cylindrical shell structure with the edge leaning against compressible foundation soil is analyzed. Different materials are considered individually for the models of each structure shell and infill component (metal or reinforced concrete shell, and granular or elastic infill in a shell and foundation soil loaded by the structure). Contact conditions between 1) the infill and the shell’s inner surface and 2) between the foundation material and the shell edge are analyzed. An example of calculating strain conditions in the shell …

Practical Considerations In Determining Timber Pile Depth Using The Sonic Echo Method, Ali F. Jwary

Civil Engineering ETDs

The Federal Highway Administration indicates that about 85,000 bridges in the United States have no original contract documents with information about the type, depth, geometry and material of their foundations (FHWA, 2010). Furthermore, the National Bridge Inventory (NBI) provides information about 86,133 bridges nationwide that are rated as scour critical because of unknown foundation condition. In New Mexico, there are more than 281 bridges with unknown foundations, which are owned by the New Mexico Department of Transportation; 71 of these are timber bridges. These data indicate a serious problem that needs decisive action to assess the unknown bridge foundation characteristics …

Bicp Global Bim Study - Lessons For Ireland’S Bim Programme, Barry Mcauley, Alan Hore, Roger West

Reports

The Construction IT Alliance (CitA) has been promoting the benefits of digitisation in the construction and engineering industry in Ireland since its formation back in 2002. Whilst the Alliance has always strived to ensure that its members are exposed to a wide spectrum of contemporary digital tools and processes, the concept of Building Information Modelling (BIM) has dominated the focus of its activities over the past five years.

BIM can be described as a digital tool that facilitates everybody to better understand a building or structure through the use of a digital model which draws on a range of data …

Site Specific Sinkhole Risk Assessment In Central Florida Using Cone Penetrometer Testing, Ryan Shamet

Electronic Theses and Dissertations

As Florida's population is expanding and greater fluctuations in groundwater levels are being recorded, Central Florida has been experiencing a higher frequency of sinkhole occurrences than ever before in recorded history. Sinkholes in Central Florida are formed by a combination of bedrock weathering and overburden soil erosion due to the groundwater recharge and are a part of Florida's past and future geology. The initial stage of a sinkhole is referred to as soil raveling and is the most effective time to perform soil improvement measures, such as grouting, to mitigate further expansion of a subterranean void. Subsurface exploration tests, commonly …

Air Injection As A Scour Countermeasure At Bridge Piers, Ravi Teja Reddy Tippireddy

Dissertations, Master's Theses and Master's Reports

Local scour is a major cause of concern for the stability of bridge piers and the safety of the public using the bridges. Structural countermeasures and flow-altering devices have been developed to deal with local scour. Many armoring structural countermeasures are very effective and efficient in clear water conditions but are susceptible to moving bed forms and leaching. The flow-altering devices are effective in both clear water conditions and moving bed forms, but are prone to clogging, less efficient in changing flow direction, etc. This study aims to reduce the local scour by injecting air in order to reduce the …