Towards a GIS-T database design and implementation for public transit planning: the case study of Dar-Es-salaam metropolitan city, Tanzania.

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies

Environmental indicator frameworks to design and assess environmental monitoring programs

Impact Assessment and Project Appraisal, vol. 22, n.1, March 2004, p. 47–62

Strategic design of There App’s business model: From product to multi-sided platform

The following work project illustrates the strategic issues There App, a mobile application, faces regarding the opportunity to expand from its current state as a product to a multisided platform. Initially, a market analysis is performed to identify the ideal customer groups to be integrated in the platform. Strategic design issues are then discussed on how to best match its value proposition with the identified market opportunity. Suggestions on how the company should organize its resources and operational processes to best deliver on its value proposition complete the work.

Optimisation and design of post-tensioning anchorage corner blisters in concrete box girder bidges

The design of anchorage blisters of internal continuity post-tensioning tendons of bridges built by the cantilever method, presents some peculiarities, not only because they are intermediate anchorages but also because these anchorages are located in blisters, so the prestressing force has to be transferred from the blister the bottom slab and web of the girder. The high density of steel reinforcement in anchorage blisters is the most common reason for problems with concrete cast in situ, resulting in zones with low concrete compacity, leading to concrete crushing failures under the anchor plates. A solution may involve improving the concrete compression and tensile strength. To meet these requirements a high-performance fibre reinforced self-compacting mix- ture (HPFRC) was used in anchorage corner blisters of post-tensioning tendons, reducing the concrete cross-section and decreasing the reinforcement needed. To assess the ultimate capacity and the adequate serviceability of the local anchorage zone after reducing the minimum concrete cross-section and the confining reinforcement, specified by the anchorage device supplier for the particular tendon, load transfer tests were performed. To investigate the behaviour of anchorage blisters regarding the transmission of stresses to the web and the bottom slab of the girder, and the feasibility of using high performance concrete only in the blister, two half scale models of the inferior corner of a box girder existing bridge were studied: a reference specimen of ordinary reinforced concrete and a HPFRC blister specimen. The design of the reinforcement was based in the tensile forces obtained on strut-and-tie models. An experimental program was carried out to assess the models used in design and to study the feasibility of using high performance concrete only in the blister, either with casting in situ, or with precast solutions. A non-linear finite element analysis of the tested specimens was also performed and the results compared.