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Grout is a high-slump cementitious material frequently used in masonry construction. The primary use of masonry grout is to fill the voids of the concrete masonry units and bind the reinforcement to the structure. However, masonry grout contributes significantly to the overall structural mass; proportionally increasing the applied loads in a seismic event. The motivation of this research focuses on reducing structural mass, therefore decreasing seismic forces, by utilizing lightweight grout. The use of lightweight materials has seen an increase due to the success of lightweight concrete. The Building Code Requirements for Structural Concrete (ACI 318) allows the use of lightweight concrete as long as the prescribed reduction factor is applied to the design. Masonry construction has two main components: concrete masonry units and masonry grout. The Building Code Requirements for Masonry Structures (TMS 402) allows the use of light masonry units but, at the time of this research, lightweight grout is not an acceptable building material. Similar to ACI 318, TMS 402 could apply a reduction factor so that lightweight grout can be utilized. Previous research has focused on the individual components of a masonry structure such as mortar, masonry units, and grout. However, the purpose of this research is to quantitatively compare the compressive strengths and modulus of elasticity for lightweight grout with that of normal weight grout in masonry prisms. The results of the data show a trend that at lower normal weight prism compressive strengths, there is no statistical difference in the use of lightweight grout and normal weight grout. However, as normal weight prism strength increases, the differences between the normal weight and lightweight aggregates can be seen as the lightweight prisms are not as strong as their normal weight counterpart.

The work described in this paper serves to develop earthquake ground motion suites for Memphis, Tennessee. These ground motion suites are useful as design ground motions which may be used in either linear or nonlinear response history structural analysis of bridges and buildings. Ground motion suites for multiple site classes were generated using current design specifications for both bridges (AASHTO) and buildings (ASCE 7-16). Target response spectra were defined for each site class and each structure type. A bin of 100 candidate records was collected from the PEER NGA-West2 database based on appropriate magnitudes and site conditions for Memphis. From these candidate records, eleven-record suites were compiled by establishing match of ground motion spectral shape to target spectra shapes, followed by computation of scale factors to minimize mean-square-error between the target and ground motion spectra. Where necessary, initial scale factors were modified to ensure that all criteria in the design specifications were satisfied. The various suites may be used directly for structures where the target spectrum closely matches one of those used here. The 100 candidate records may be used as a starting point for projects with target spectra near that for Memphis, but with target spectra departing from those used here.

Structural steel special moment resisting frames (SMRF), special concentrically braced frames (SCBF) and eccentrically braced frames (EBF) are designed as a part of building frames to control the damage during earthquakes. Choosing an appropriate lateral force resisting system (LFRS) is related to many parameters. The dynamic response of structural systems is affected by the flexibility of the foundation system adopted. This effect is referred to as soil structure interaction (SSI). Structural damping in nonlinear response history analysis (NLRHA) is routinely assumed to be elastic and viscous. The Rayleigh damping formulation is one common damping approach. Firstly, in this study, a nonlinear RHA simulation procedure was employed. Foundation flexibility with fully nonlinear SSI effects was incorporated in the NLRHA. In addition, the effect of various Rayleigh damping components on the elastic and inelastic dynamic response of the structures was studied. Secondly, the performance levels of SMRF, SCBF and EBF systems were addressed, with and without the foundation flexibility. Thirdly, the simulation procedure was developed to incorporate the embedded depth in the analysis of the SMRF, SCBF and EBF structural systems. In the fourth part, the effect of the near foundation zone on the dynamic response of the SMRF with embedded depth was addressed, proposing a correlation to estimate the dynamic properties of the soil in the near foundation zones. Rayleigh damping approach was mainly affected by the flexibility of the foundation and led to a different dynamic response compared to the fixed base condition, and the dynamic response of the special LFRS was significantly affected by the kind of the motion and the site properties. The existence of soft site condition in the near-foundation zone led to isolate the SMRF systems and change the performance level from the “collapse” to the “life safe”.

De-icing salts contain chemicals, specifically magnesium chloride (MgCl), that can be detrimental to concrete. Creating a lower permeability concrete would slow the rate and amount of intrusion of these harmful de-icing chemicals. Reducing the rate and amount of intrusion of de-icing chemicals will reduce the deleterious effects of de-icing chemicals. The Tennessee Concrete Association (TCA) inquired for ideas beyond the specifications in American Concrete Institute Residential Code Requirements for Structural Concrete (ACI 332-14). The specifications outlined in ACI 332-14 are not strenuous enough to create a durable concrete that has the ability to withstand the deleterious effects of de-icing chemicals. The main objective of this research was to design and develop concrete mixtures that go beyond the requirements outlined in ACI 332-14 in order to produce a high durability concrete. A total of 6 mixtures were produced: three current commercial and residential mixtures that are currently being used in Tennessee, one current commercial and residential mixture with a commercial sealer applied to it, and two commercial and residential enhanced durability (CRED) mixtures that go beyond the specifications outlined in ACI 332-14. The two CRED mixtures and the sealed mixture were compared to the three current commercial and residential mixtures and to each other to determine the overall durability of the concrete. Each mixture was subjected to a durability conditioning process to expose the mixtures to de-icing chemicals. The mixtures were tested in an undamaged state and then at two different intervals after the durability conditioning process began. The comparison tests included: compressive strength, splitting tensile strength, static modulus of elasticity, and absorption after boiling. The test results showed that both CRED mixtures and sealed mixture were statistically superior to or had no significant difference in compressive strength loss and tensile strength loss when compared to current commercial and residential mixtures. Due to number of test results, statistical analysis was not conducted on static modulus of elasticity. However, the results obtained for this property showed that the current commercial and residential mixtures had a large decrease while the CRED mixtures and sealed mixture increased or slightly decreased over the course of this research. The results for absorption were compared to high-performance concrete (HPC) criteria. The current commercial and residential mixtures had initial values of absorption that were at or above the criteria and ended well above the criteria. The CRED mixtures had initial and final values within the range for HPC. The results obtained prove that using either the CRED mixtures or the sealed mixture will significantly increase the durability of the concrete in comparison to current commercial and residential mixtures.

Stormwater runoff delivered through conventional drainage systems including pipes, gutters, and sealed channels is generally left not infiltrated and or evapotranspirated. These systems increase the quantity of runoff and pollutants of the receiving waterways. A vegetated swale is, however, one of the stormwater control measures which has been proven to reduce runoff and pollutants discharged into receiving waterways. Swale runoff volume reduction has been reported as 52%-59%. To assess the actual extent, the geometric properties of the vegetated swales, field surveys need to be conducted. Conducting these field surveys on the Tennessee Department of Transportation (TDOT) highways is cost-prohibitive owing to the very large mileage of highways in Tennessee. However, an automated Geographic Information System (GIS) tool called GIS-based Vegetated Swale Algorithm for TDOT Highways (GV-SwATH ) has been developed by the Civil and Environmental Engineering Department at Tennessee Technological University for extracting the vegetated swales using spatial datasets along the State Route 111 (SR 111) and Intestate 40 (I-40) highways in Putnam County, Tennessee. The area of the extracted swales will aid in estimating the flow after rainfall events. The tool works using four different approaches namely; Buffer plus Intensity, Buffer plus Slope, Polyline plus Intensity and Polyline plus Slope. The objective of this thesis was to ascertain the degree of efficiency of the GV-SwATH tool in delineating vegetative swale along two highways in Tennessee. To achieve the objective, analysis was done to assess the performance of the GV-SwATH tool in delineating the vegetated swales along selected sites on the SR 111 and I-40 highways. Statistical analysis was done using observed data collected from Google Earth Pro® Aerial Imagery and through field survey using the Trimble® handheld GPS device on selected sites on the two highways. Analysis done indicates that the Buffer plus Slope approach works better for the SR 111 sites while Polyline plus Intensity works better for the I-40 sites. This was because the slope remains fairly constant for the SR 111 sites compared with the I-40 sites which showed variability in slope. The intensity approach was able to distinguish between the ground cover, the reason why it works better for I-40 sites owing to different ground covers that exist on the I-40 stretch. Overall, the tool performs better for SR 111 sites as compared with the I-40 sites due to the sensitivity of input parameters. Nash–Sutcliffe Efficiency (NSE) value of 0.84-0.96 was recorded for SR111 which is an indication of satisfactory performance. NSE value of 0.20-0.98 for I-40 was recorded for the I-40 sites. Lowest NSE values for the I-40 sites were recorded when the Buffer approach was utilized. Percent Bias (PBIAS) values for SR 111 lie within -28% and 29% while that of I-40 lies within -36% and 42% for different observed datasets.

Transient seepage analysis of rapid drawdown (RDD) loading condition for dams and levees assumes a state of full saturation prior to drawdown. This assumption is likely incorrect for levees due to the relatively short duration of floods prior to drawdown; and hence requires that methods be developed to estimate the extent of saturated zone within levees after floods for undrained RDD analysis. Levees can be founded on soils with a range of permeability, and therefore it is important to investigate how levee foundations influence levee through-seepage under transient conditions. Also the initial conditions of a levee prior to flooding play an important role in estimating the hydraulic conductivity of soils as seepage progresses through levees under transient conditions. Transient seepage analysis of unsaturated levee soils requires that the hydraulic conductivity and volumetric water content be estimated based on the soil water characteristic curve (SWCC) and hydraulic conductivity function (HCF), and these are both dependent on the initial suction values within the levee. As part of a broader research focused on prediction of post-flood levee saturation, this thesis examines trends in the position of the phreatic surface within levees at the start-of-drawdown by considering the effects of (i) levee foundation soils and (ii) initial soil suction within levees. Conservative methods are developed for predicting the phreatic surface based on parametric consideration of the soil coefficients of consolidation, levee geometry, flood hydrograph, and initial soil suction. The study found that foundation soils influence seepage within levees when their coefficient of consolidation is greater than that of levee soils. However, initial distributions of suction have little influence in driving seepage from the upstream slope of levees. The methods will allow for the prediction of start to drawdown phreatic surface for RDD analysis, and may be applied to different levee conditions and flood scenarios.

Compacted clay slopes are often constructed for civil engineering projects, such as highway embankments and land development. Many times, only limited information about soil properties is available at the time of design (e.g., soil classification, Atterberg limits, and relative compaction specifications). Design of compacted and stiff clay slopes is most often controlled by drained or long-term conditions. Over a long period of time, these clays tend to lose their initial compaction or stiff consistency due to various mechanisms, such as weathering and excavation. These mechanisms eventually cause the strength of the clay to reduce to a peak normally consolidated strength, which is also known as the fully softened shear strength. This study seeks to evaluate the use of an efficient response surface method that could be used in preliminary design of such slopes. Six different landslides in central Tennessee were analyzed in an attempt to validate a preliminary slope design method that is simpler to perform than limit equilibrium analysis. Each of these slopes was analyzed with two different approaches: a closed-form response function and limit equilibrium analysis using Slide 8.0. The limit equilibrium software was used to check the accuracy of the response function. For slopes with geometry and soil conditions that fell within the range used to develop the response function, it was found to be an appropriate means to estimate the factor of safety. For most of the slopes a pore pressure ratio of 0.1 to 0.3 caused a factor of safety equal to 1.0. These conclusions allowed the development of preliminary design charts for slopes angles 2H:1V or flatter. Acknowledging the uncertainty in soil properties and response function a reliability approach was used rather than a specific factor of safety. The Taylor series First-Order Second Moment (FOSM) method was used to determine sets of design conditions with a consistent reliability or probability of failure. Sets of design charts were made for probabilities of failure of 1% and 5%. These charts provide a simple way of estimating the maximum slope height and/or angles that can be used in preliminary design of stiff clay cut slopes and compacted clay embankments. For future work this method can be compared to other methods to show any flaws that may be obtained in this method or other forms of analysis. This method also gives the ability to determine whether or not slopes in central Tennessee are being design for long term conditions.

The Fixing America’s Surface Transportation Act (FAST act) changed the existing weight limit restrictions for highway vehicles. The new restrictions now allow for certain heavier vehicles to traverse highways without acquiring permits. In response to this, the Federal Highway Administration (FHWA) has required state transportation departments to load rate all bridges and structures within a mile of the interstate system for two new loading configurations. The configurations are named EV2 and EV3 and must be evaluated as legal loads per the Load and Resistance Factor Rating method. In addition, the FHWA has developed a new load posting procedure based on the rating results of the new emergency vehicle configurations. The main objectives of this research are to compile a database of culvert ratings for new emergency vehicle loading, conduct a parametric study of the rating results, and investigate possible changes that can be made to culvert models to increase accuracy. This thesis summarizes an investigation into the effects of new emergency vehicle loading configurations on load ratings of concrete culverts in Tennessee. The Tennessee Department of Transportation funded the research and provided all pertinent information. Based on the information provided, structural computer models for all of the culverts were built using the software program AASHTOWare. The culverts were load rated for different loading configurations. The ratings for every load configuration for each culvert was recorded. Upon completion of load rating the culverts affected by new emergency vehicles, it was found that EV2 and EV3 ratings were less than HL-93 truck and HL-93 tandem operating ratings for every culvert. There were culverts whose ratings were sufficient for HL-93 truck and tandem loading, but are now insufficient for the new emergency vehicle loading. The reason for the decrease in ratings is due to EV2 and EV3’s heavier weight and shorter length compared to HL-93 loading, larger required live load factor of 2.0 for EV2 and EV3 loads for buried structures versus 1.35 for HL-93 truck and tandem loads, and lack of compliance of EV2 and EV3 loading to federal bridge formula B weight restrictions. The new emergency vehicle load posting procedure and the relatively low EV2 and EV3 load ratings will significantly impact recommended load postings for culverts in Tennessee. The correlations found between HL-93 and emergency vehicle loading are strong and can be used to reasonably estimate EV2 and EV3 ratings when HL-93 ratings are available.

Ground motion selection and modification for nonlinear response history analysis (NRHA) is typically based on mean, elastic acceleration target spectra. However, structures are typically designed to behave in an inelastic manner during strong ground shaking, with inelastic displacement the variable of prime interest. In order to place confidence in the use of elastic acceleration target spectra as the basis for NRHA, the variance of inelastic displacement needs to be studied. Since seismic response is typically presented as log-normally distributed, a comparison of the variability in inelastic displacement and variability in elastic acceleration can be performed. Further, knowledge of the variance of inelastic spectral displacement can lead to a better understanding of the appropriate number of records required for analysis. A total of 66 design ground motion records were selected and scaled based on site-specific hazard conditions to generate elastic acceleration and inelastic displacement spectra. Of the 66 records, 55 were separated into five non-pulse type design suites containing 11 records for varying significant earthquake durations: 10-20 seconds, 20-30 seconds, 30-40 seconds, 40-50 seconds, and 50-99 seconds. The remaining 11 records are comprised of pulse-type ground motions that belonged to a single characteristic bin. Each design suite was used to develop elastic acceleration and inelastic displacement spectra in order to compare the variability in inelastic displacement to the variability in elastic acceleration. The study shows that the use of elastic acceleration target spectra for ground motion selection and modification for NRHA is more appropriate for structures with a fundamental period typically less than 1-second. For fundamental structural periods greater than 1-second, the variability and trend in inelastic displacement spectra changes significantly with respect to significant earthquake duration, ductility, and post-yield stiffness.

Flood Impact Assessment (FIA) is an integral part of flood risk management (FRM) that requires extensive data collection and rigorous modeling. Elevation data is one of the main inputs for this venture that is often fulfilled by digital elevation models (DEM). DEM provides a continuous representation of terrain and may cover a large area. However, the accuracy and details of terrain in a DEM depend on its source and spatial resolution. Regardless of the source and spatial resolution, DEMs most often do not provide accurate river bathymetric elevations thus misrepresent conveyance. Additionally, DEM is a static dataset providing a snapshot of the terrain during the time of data acquisition. Therefore, DEM cannot show any change in terrain that may have happened afterward. But, waterbodies such as rivers are among the most dynamic terrain features that change both in short (annual) and long term (decadal) scale. Therefore, representing the conveyance and capturing the planform dynamics of rivers in terrain dataset is especially critical for FIA. These shortcomings of a DEM is often addressed via merging ground surveyed data with DEM. However, collecting ground surveyed data is challenging in remote, inaccessible and data-poor areas. Thus, the objective of this dissertation is to assess the uncertainties in DEMs for representing river morphology (planform and conveyance) and propose DEM correction algorithms for producing morphologically consistent DEM to improve riverine FIA in data-poor areas. This dissertation has proposed three algorithms (or methods) that can predict planform and effective river conveyance for developing morphologically consistent DEM. The methods are Slope Adjusted Mean Bed Level Elevation (SAMBLE), River Bathymetry via Satellite Image Compilation (RiBaSIC) and Altimeter-based River Bathymetry via Satellite Image Compilation (Alt-RiBaSIC). They are designed to suit hydrologically well gauged, partially-gauged, and ungauged areas. The algorithms are tested on multiple rivers representing different river characteristics and varying levels of data-gap. The application of these algorithms for FIA over the Kushiyara River in Bangladesh showed DEMs corrected by each of these algorithms outperform the FIA via uncorrected DEM. Therefore, the algorithms are expected to be useful in FIA in other data-poor areas.

Post-yield stiffness is a key parameter in determining the inelastic displacement demand on structures during strong ground shaking. Current models in AASHTO assume zero post-yield stiffness (elastic-perfectly-plastic behavior). While options other than bilinear models are available, the level of detail available in preliminary design is often insufficient to completely define these models. A simple bilinear model is needed which has the capability of providing accurate estimates of maximum displacement, ductility demand, and energy dissipation through effective damping. The analysis was conducted using a pushover analysis with SeismoStruct. Load displacement plots for varying parameters including axial load ratio, column height to diameter ratio, longitudinal reinforcement ratio, and volumetric ratio of confinement steel ultimately serve as the basis for comparison to other analytical models. The load-displacement graphs were used to simplify the seismic response of the bridge column into an equivalent bi-linear representation with yield and maximum displacement identical to values from pushover analysis. These representations were then compared to current AASHTO models assuming zero post yield stiffness to assess the accuracy of current models and the implications to bridge designers.

Concrete has many durability issues that cause failure, which can be worse than applied loads. Cyclic freezing and thawing is one of the durability issues and can be mitigated by the use of air-entraining admixtures (AEA). These chemical admixtures create voids in the concrete to help reduce the degradation of the cyclic freezing and thawing. However, the use of AEA with certain fly ashes has proved problematic. The Environmental Protection Agency puts limits on the amount of nitrogen oxide emissions from coal combustion plants and this is affects the fly ash (FA) that is being produced. These limitations create a FA that does not meet the standards for Class C and F fly ash, therefore the FA cannot be used in concrete and is disposed of in landfills. This marginal fly ash (MFA) has a high carbon content and acts like an active carbon. It will absorb the chemical air-entrainers that are used to prevent freezing and thawing degradation. Thus, alternative means of entraining air are sought. Superabsorbent polymers (SAP) are used in the production of diapers because the polymers can absorb large amounts of water. SAP has been used in concrete for internal curing; because the SAP will absorb water while the concrete is in its fresh state. As the concrete sets, it will draw water from the SAP and use it for cement hydration. Voids are left in the hardened concrete after the water is removed from the SAP. The voids left in the concrete are similar to the voids created by AEA. For this reason, the SAP was used as a physical air-entrainer in this research. Shown in this research are concrete mixtures using AEA and SAP each containing different types of FA. One Class F FA is commonly used in concrete mixtures while the other two types are MFA obtained from landfills. The concrete mixes were subjected to cyclic freezing and thawing test. The AEA concrete mixes all passed the freezing and thawing test and the dosage of AEA was increased with the use of the marginal fly ash. The water cured physically air entrained concrete all failed the freezing and thawing test. Allowing the physically air entrained concrete to dry prior to freezing and thawing proved beneficial. Thus, SAPs may be used as a substitute for AEA with MFA so long as curing and drying is controlled.

The Hernando DeSoto Bridge in Memphis, Tennessee, was implemented with a static-based structural health monitoring system. This was due to the seismic vulnerability and importance to travelers crossing the Mississippi River. Using specifically placed sensors throughout the structure, one objective was to examine the functionality and performance of the friction pendulum bearings implemented in a seismic retrofit. In addition, it was desired to track the bearing movements and member strains before, during and after a seismic event. The implemented structural health monitoring system consists of strain gages, short-range displacement gages and long-range displacement sensors implemented on the west and east ends of the main arch section. Vibrating wire strain gages were placed on each member framing into the bearings to determine the force distributions. Vibrating wire short-range displacement gages were also installed at the east and west arch piers. Using the force distributions and thermal movements captured, the coefficient of friction in each bearing was calculated and compared to the design values. In addition, high-speed non-contact laser displacement sensors were installed at each bearing to more comprehensively track the bridge movements during a seismic event. All the sensor data is being visualized in a real-time monitoring display. The display also includes a basic alerting system with threshold criteria to aid in proactively detecting and addressing any anomalies that may occur on the structure. The result of the bearing performance investigation for the west end (Pier A) indicated adequate performance. The coefficient of friction for the upstream and downstream bearings were 0.05 and 0.06, respectively. The design (installation) value was 0.06. In addition, the measured thermal movements of the west end bearings were within 5% of the theoretical movement. Bearing performance could not be determined at the east end (Pier C) as limited thermal movement was measured. Furthermore, relatively low member force build-up was measured. These responses were attributed to probable substructure movement. Tracking the substructure movement is proposed for system upgrades and future research on the Hernando DeSoto Bridge.