The topic of this diploma thesis is an analysis of a process of deformation measure-ments performed during bridge structure load tests and their following evaluation. The aim of this thesis is to describe commonly used methods of measurement, their principles and difficulties, and to find ways of usage in modern methods. The main point of the thesis is to solve the problematic of suspension wire – to find through laboratory measurement suit-able alternatives to so far most commonly used steel wire. The first part of the thesis is focused on theoretical hypotheses for load testing of bridge structures and is based on the ČSN 73 6209 norm, including description of the measurement methods. The next part is focused on the evaluation of particular bridge load test and practical evaluation of the laboratory experiment.

The aim of the offered thesis is an analysis of usage of uncommon concrete matrix and its contribution to steel-concrete composites structures. It especially refers to the area of internal supports, where usually acts negative bending moments. These statical systems are very often used for bridge structures, or even for building constructions. Nowdays, the static infuence of concrete at the area of negative moment is neglected. Only the steel part of cross section and steel reinforcement are included to the static action. This work is focused on the usage of tensile strength of uncommon concrete. The improvement of tensile strength of cement matrix is due to glass fiber reinforcement acting as scattered reinforcing. The introduction is focused on common approach of design of the structures mentioned above. Next, there is a part which describes possibilites of using fibre reinforcing until nowdays.

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Full scale lateral load tests were performed on four piles located at various distances behind MSE walls. Three of the four test piles were production piles used to support bridges, and the other pile a production pile used as part of the bridge abutment. The objective of the testing was to determine the effect of spacing from the wall on the lateral resistance of the piles and on the force resisted by the MSE reinforcement. Lateral load-displacement curves were developed for pile at various spacing and with various reinforcement ratio (reinforcement length, L divided by wall height, H). The force in the reinforcement was measured using strain gauges. Lateral load analyses were performed to determine the minimum spacing required to eliminate any effect of the wall on the pile resistance (p-multiplier of 1) and the reduction in soil resistance at closer spacings (p-multiplier less than 1). With the addition of the data fro Price (2012) tentative curves have been developed showing p-multiplier vs. normalized spacing behind wall for a length to height ratio of 1.6, 1.2, and 1.1. The data suggest that with a L/H ratio of 1.6, a p-multiplier of 1 can be used when the normalized distance from the back face of the MSE wall to the center of the pile is at least 3.8 pile diameters. When the L/H ratio decreases to 1.2 and 1.1 a p-multiplier of 1 can be used when the pile is at least 4.5 and 5.2 pile diameters behind the wall respectively. For smaller spacings, the p-multipliers decreased essentially linearly with normalized distance from the wall. A plot showing the increased load in the reinforcement as a function of distance from the pile has been developed. The data in the plot is normalized to the maximum lateral load and to the spacing from the wall to the pile. The best fit curve is capped at a normalized tensile force of approximately 0.12. The data show that the increase in tensile force on the reinforcement when a lateral load is applied to the piles decreases exponentially as the normalized distance from the pile increases. The plot is limited to the conditions tested, i.e. for the reinforcement in the upper 3 ft. of the wall with L/H values at 1.2.

The geotechnical parameters of the different lithologies are of great importance regarding mining, infrastructures development and safety. The main aims of this thesis project are the evaluation of the previously acquired point load tests (PLT) data and the acquisition of a larger set for the various lithologies and alterations. In addition, the correlation to the Leeb Hardness test (LHT) method, and the determination of correlation factors (K) for estimating the uniaxial compressive strength (UCS) index from PLT data for various lithologies were evaluated. In total, 5236 previously PL tested samples, 1113 newly PL tested samples and 569 LHT measurements were obtained. The results showed that the highest values come from the footwall lithologies (Sp) ranging between 11-19 MPa, while the hanging wall lithologies (Qp) fall in range 10-14 MPa and the different ore types between 6-11 MPa. The correlation between PLT and LHT was poor, with the results completely overlapping for all country rock lithologies in the range 800-900 LHD, while the ore types fall in the range 600-700, and anhydrite at 500 LHD. On the other hand, the correlation factors K for the lithologies tested vary between 13-20 for the weaker and more altered rock types and 25-30 for the stronger ones, correlating well when compared to the actual UCS values found in the literature. In conclusion, it is evident that the LHT is not able to substitute the PLT as it captures different properties of the rock. The conversion from PLT to UCS gave rather accurate results, with slightly different correlation factors K for the tested lithologies.

A large amount of research has been conducted to investigate the influence of incorporating geosynthetics in highway pavements in laboratory-scale and full-scale experiments, and performance improvement has been well documented. In most cases, geosynthetics have been found to improve rutting resistance or reduce vertical pressure on the subgrade. Airfield pavements are typically thicker than highway pavements and are subjected to higher wheel loads and tire pressures. Thus, the benefit of geosynthetics within airfield pavements may not be as pronounced as that observed in relatively thin highway pavements. Prior to the writing of this dissertation, few documented studies focused on the performance of geosynthetic inclusion in airfield pavements and existing Department of Defense (DOD) guidance for geosynthetic inclusion had not been updated for several decades. The primary objectives of this dissertation were to update the DOD geosynthetic design methodology, to interpret results of laboratory-scale and full-scale experiments conducted specifically to evaluate geosynthetic performance in airfield pavements, and to determine if a competitive market exists for geosynthetic inclusion in airfield pavements. The main body of this dissertation is a compilation of four complementary articles that build upon the primary components of the main objectives. Chapter 1 and Chapter 2 present an introduction and a literature review, respectively. Updates to the DOD design methodology are presented in Chapter 3, results of laboratory-scale and full-scale evaluations are presented in Chapter 4 and Chapter 5, respectively, and potential implications of geosynthetic inclusion in airfield pavements are presented in Chapter 6. Chapter 7 presents overall conclusions and recommendations. Overall, it was found that, while some geosynthetics can be beneficial in airfield pavements, more rutting than would typically be allowed on an operational airfield was required to realize a meaningful performance benefit. In cases where geosynthetics were included in an airfield pavement, it was found that an extension of service life rather than a reduction in aggregate thickness was more optimal in assigning a geosynthetic value. Finally, the results of this dissertation indicated that geosynthetic inclusion in airfield pavements did not yield the same benefit level as that documented in the literature for highway pavements.

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As America's infrastructure ages, many of the nation's bridges approach the end of their service life. In order to develop a method for handling the rising number of deficient and functionally obsolete bridges, nondestructive tests and evaluations must be undertaken. Valuable information from these tests regarding the strength and condition of bridges will help in making decisions about their rehabilitation and replacement. Two adjoining open spandrel reinforced concrete arch bridges in downtown Appalachia, Virginia were selected for live load testing by Virginia Department of Transportation (VDOT). Both bridges have supported an increasing amount of extreme coal truck traffic throughout their service life and are essential to the efficient transport of coal in the region. Because of their age, having been built in 1929, and the amount of visible damage and repairs, VDOT was concerned about their remaining capacity and safe operation. The live load tests focused on global behavior characteristics such as service strain and deflection as well as local behavior of the arches surrounding significant repairs. It was found that the strain and deflection data collected during load testing displayed linear elastic behavior, indicating excess capacity beyond the test loads. Also, given the loading applied, the measured strains and deflections were small in magnitude, showing that the bridges are still acting as stiff structures and are in good condition. Data collected during these tests was compared to results from a finite element model of the bridges to determine the coal truck size which is represented by the live load test loading configurations. The model comparisons determined the test loads produced comparable deflections to those produced by the target coal truck load. Through this approach, a recommendation was given to VDOT regarding the satisfactory condition of the aging bridges to aid in the process of load rating and maintenance scheduling for the two bridges. / Master of Science

Over the past 50 years, several advancements have been made in the research area of the mechanics of unsaturated soils. These advancements can be categorized into two groups; (i) development (or improvement) of testing techniques (or apparatus) to determine the mechanical properties of unsaturated soils and (ii) development of (numerical, empirical or semi-empirical) models to estimate the variation of mechanical properties of unsaturated soils with respect to suction based on the experimental results. Implementation of the mechanics of unsaturated soils in conventional geotechnical engineering practice, however, has been rather limited. The key reasons for the limited practical applications may be attributed to the lack of simple and reliable methods for (i) measuring soil suction in the field quickly and reliably and (ii) estimating the variation of mechanical properties of unsaturated soils with respect to suction. The main objective of this thesis research is to develop simple and reliable techniques, models or approaches that can be used in geotechnical engineering practice to estimate sol suction and the mechanical properties of unsaturated soils. This research can be categorized into three parts. In the First Part, simple techniques are proposed to estimate the suction values of as-compacted unsaturated fine-grained soils using a pocket penetrometer and a conventional tensiometer. The suction values less than 300 kPa can be estimated using a strong relationship between the compressive strength measured using a pocket penetrometer and matric suction value. The high suction values in the range of 1,200 kPa to 60,000 kPa can be estimated using the unique relationship between the initial tangent of conventional tensiometer response versus time behavior and suction value. In the Second Part, approaches or semi-empirical models are proposed to estimate the variation of mechanical properties of unsaturated soils with respect to suction, which include: - Bearing capacity of unsaturated fine-grained soils - Variation of bearing capacity of unsaturated fine-grained soils with respect to matric suction - Variation of initial tangent elastic modulus of unsaturated soils below shallow foundations with respect to matric suction - Variation of maximum shear modulus with respect to matric suction for unsaturated non-plastic sandy soils (i.e. plasticity index, Ip = 0 %) In the Third Part, approaches (or methodologies) are suggested to simulate the vertically applied stress versus surface settlement behavior of shallow foundations in unsaturated coarse-grained soils assuming elastic-perfectly plastic behavior. These methodologies are extended to simulate the stress versus settlement behavior of both model footings and in-situ plates in unsaturated coarse-grained soils. The results show that there is a reasonably good comparison between the measured values (i.e. soil suction, bearing capacity, elastic and shear modulus) and those estimated using the techniques or models proposed in this thesis research. The models (or methodologies) proposed in this thesis research are promising and encouraging for modeling studies and practicing engineers to estimate the variation of mechanical behavior of unsaturated soils with respect to matric suction.