Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1999. / Includes bibliographical references (leaves 45-46). / by Philip Michael Iannaccone. / M.Eng.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1996. / Includes bibliographical references (p. 73-74). / by Stephanie Marder Vaughn. / M.S.

Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 107-113). / This paper assesses two cast-iron arch bridges of Thomas Telford (1757-1834) - Bonar Bridge (1810-12) and Mythe Bridge (1824-26) - to draw a broader conclusion about his career in bridge building. The bridges are introduced and Telford's design influences are investigated. While Telford was influenced by theory through the advice of his contemporaries, he was more heavily influenced by experience, especially design precedents, and most of all by his own judgment, which placed great emphasis on both practicality and aesthetics. The structural performance of the two bridges is assessed and compared. The cast-iron arch's ability to resist vertical loading is the main focus of the analysis, following Heyman's framework for limit analysis of arches. Global equilibrium and graphic statics indicate that the each rib, when acting alone, is insufficient to support asymmetric loading, demonstrating that the secondary members are necessary, and therefore that neither bridge is grossly overdesigned. Deck-stiffening effects are tested following Billington's method, and are found to be negligible. The spandrel bracing members are found to be sufficient apart from the development of tension forces in Bonar Bridge. The later Mythe Bridge performs slightly better in all areas; overall, however, the performance is very similar. Based on these results, the paper concludes that Telford chose not to refine his design substantially over the course of his career. It is argued that this was a conscious decision, based on the progression of the industry from cast iron towards wrought iron, and that these bridges are significant because they bookend the short golden age of cast iron bridges, of which Telford was the unquestionable master. / by Ellen Lane. / M. Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2005. / Includes bibliographical references (p. 183-189). / The diversity of sandstones and sandstone properties that exist in nature pose a significant problem for engineers who deal with these materials, whether in oil well exploration and exploitation or art and architectural conservation. The solution proposed in this thesis takes a highly reductionist approach to the problem. Properties of the sandstone material are first reduced to material invariant properties of the material phases present in sandstone. These are universal constants which do not vary from one sample to the other. From these material invariants, it is then possible to 'nanoengineer' the properties of a specific sandstone sample based only on a few easily measured properties - the volume fractions of the material phases. To help identify material invariant phases and reconstruct microstructure, a multi-scale think model for sandstone is developed from ESEM images as well as from the results of mineralogy, grain size, and porosimetry experiments. A nanoindentation campaign is performed to characterize sandstones at multiple scales and an innovative technique is used to separate the various indentation responses that can occur on a heterogeneous composite. Material invariant phase properties are obtained for both the sand grains and the clay minerals. A new technique for estimating volume fractions of composite materials using nanoindentation is developed and verified. Clay stiffnesses are found to be highly dependent on microstructure rather than on mineralogy, and material invariant properties are proposed. A comparison of models to estimate elastic and poro-elastic properties reveal shortcomings that motivate the development of a new predictive model. / (cont.) A multi-scale model employing a self consistent scheme and a double-porosity model is suggested and applied with excellent results predicting poroelastic properties. This model permits the 'nanoengineering' of a specific sandstone sample based only on the volume fractions of the material phases. / by Christopher Philip Bobko. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2003. / Includes bibliographical references (p. 221-236). / This thesis structures a process to support transit agencies in their decision-making when improving their current conventional bus service (CBS) towards a higher quality system such as Bus Rapid Transit (BRT). Four major tasks were conducted as follows. First a literatu re review was performed to study relevant prior research and BRT cases in operation in Pittsburgh, Los Angeles, Bogota, Curitiba, and Ottawa. Second, and based on the case studies and literature review, eight key attributes and components of BRT systems were identified. The key attributes defined were: 1) right of way priority; 2) expedited boarding and alighting; 3) knowledge-based planning and operations; 4) high frequency; 5) high reliability; 6) distinct image; 7) connectivity; 8) land use integration. The physical bus components that could be changed in order to achieve these attributes were identified as the right-of-way, stops, vehicles, fare collection system, signal priority system, and automated vehicle location (AVL) system. The third task focused on developing a prioritization process to understand the variables that would lead to achieve the first two key attributes. All components but AVL systems were identified to impact these key attributes. The evaluation process to prioritize the critical variables of each component was based on the time savings and cost associated with their implementation. Time savings were evaluated from a user standpoint as the total travel time, including access time, waiting time, and in-vehicle time. Time savings for the agency were evaluated through running time reductions. Finally, the process was applied to Chicago transit Authority Express service 49 on Western Avenue in Chicago, IL. As a result, the implementation of the prioritized variables was recommended on two phases. The first phase (1- 3 years) includes reducing the stop spacing on the X49 route to increase coverage and demand, upgrade all buses used in the route to low-floor buses, expedite fare collection process through wider use of transit cards, implement active signal priority, implement preferential treatment for buses, and finally upgrade to contact-less smart cards. The second phase (3 - 5) years, includes implementing off-vehicle fare payment and conducting further analysis to determine the cost-effectiveness and feasibility of an exclusive lane operation. / by María del Pilar Rodríguez. / S.M.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000. / Includes bibliographical references (p. 87-90). / by Heather M. "Shelley" Bramer. / M.Eng.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1968. / Bibliography: leaves 139-140. / M.S.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997. / Includes bibliographical references (p. 101-102). / by Joel D. Guzmán. / M.Eng.

Thesis: S.M. in Transportation, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 63-68). / Data from mobile phones is constantly increasing in accuracy, quantity, and ubiquity. Methods that utilize such data in the field of transportation demand forecasting have been proposed and represent a welcome addition. We propose a framework that uses the resulting travel demand and computes fuel consumption. The model is calibrated for application on any range of car fuel efficiency and combined with other sources of data to produce urban fuel consumption estimates for the city of Riyadh as an application. Targeted traffic congestion reduction strategies are compared to random traffic reduction and the results indicate a factor of 2 improvement on fuel savings. Moreover, an agent-based innovation adoption model is used with a network of women from Call Detail Records to simulate the time at which women may adopt driving after the ban on females driving is lifted in Saudi Arabia. The resulting adoption rates are combined with fuel costs from simulating empty driver trips to forecast the fuel savings potential of such a historic policy change. / by Adham Kalila. / S.M. in Transportation

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2013. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 55-61). / A study was performed to examine a possible source of fecal bacteria contamination originating from within the stormwater drainage system in Singapore. The extent of fecal bacteria presence in storm drain biofilms was evaluated as a pathway for fecal bacteria contamination. In the research, biofilms were evaluated as reservoirs for fecal indicator bacteria (FIB), FIB concentrations were measured over time within biofilms and stormwater, and relationships between FIB in biofilms and FIB in stormwater were examined. The concentrations of three bacterial groups (total coliform, Escherichia coli, and enterococci) were used as indicators of fecal bacteria contamination. In the Singaporean districts of Choa Chu Kang and Toa Payoh, five locations within the storm drains were monitored once per week each between January 8, 2013 and January 22, 2013. Well-developed biofilms were observed and measured using concrete coupons in the storm drains at Choa Chu Kang Crescent, Verde View, Lorong 6 Toa Payoh, and two points at Lorong 8 Toa Payoh. An initial biofilm growth condition was observed for secondary research at Nanyang Technological University. The biofilms in the storm drains were observed to be reservoirs for FIB due to measured concentrations of each fecal indicator. The measured FIB concentrations fluctuated over time in the biofilms and the overlying storm drainage waters due to natural processes within the biofilms and the storm drain environments. Greater fluctuations in FIB concentrations in biofilms than in storm drainage waters indicate that the stormwater is more stable and has additional sources of FIB contributing to the contamination. FIB detachment from biofilms is a potential pathway for fecal bacteria contamination of stormwater. / by Tsung Hwa Burkhart. / M.Eng.