TY - BOOK AU - Garcia, Ronald R. AU - ED - ED - ED - ED - SN - 2 PY - 0000///46 CY - PB - KW - KW - 2 KW - 0 KW - 6 KW - 20 N1 - Thesis (M.A.) -- Pamantasan ng Lungsod ng Maynila, 2004.;A directed study presented to the faculty of Graduate School of Engineering in partial fulfillment of the requirements for the degree Master of Engineering (MEng) with specialization in Structural Engineering; 5 N2 - ABSTRACT: Generally, there are different types of bridge structures that were built several years ago and are still in use today. Bridges like the arch bridge, concrete box bridge, cabled stayed bridge or the suspension bridge are among these types. However, the most integral component in any transportation network are the common highway bridges. Common highway bridges typically consist of slab-on-stringer configuration. They are usually made of concrete deck slab, which rest on a set of longitudinal girders. Most of these bridges that were built in the past have performed so well and that they are so durable and because of these reasons, most people and even engineers take them for granted. Old bridges don't die or fade away, they deteriorate. Thus it is very necessary to load rate these existing bridges, particularly if they have developed material deterioration and loss of section strength, bet these due to poor condition-survey or inspection, and consequent lack of maintenance (repair and strengthening), accidental damages, overload, under design, poor quality construction or poor detailing in the first place. Three bridges were selected among the common highway bridges sets of plans derived from DPWH. These bridges were composed of different kind of girders that support the deck slab above the common highway bridges, i.e., the San Diego Bridge for reinforced concrete girders, the Bagsit Bridge for the prestressed girders and the Amlosong Bridge for the plate girders. The main objective of the study is to determine the load rating of these 3 selected common highway bridges in the Philippines, by making approximate methods of calculations of the live load capacity of the bridges in accordance to the Manual for Condition Evaluation of Bridges, 2nd edition 1994, with interim revisions through to 2001 (hereinafter referred as the (Manual). The study aims also to analyze the adequacy of the existing bridges superstructure element, i.e., the cantilever slab using the Load Factor Method of AASHTO Standard Specifications for Highway Bridges, 17th edition 2004 (hereinafter referred to as Standard Specifications). These bridges were analyzed and satisfied the equations specified in the Standard Specifications that were presented in English systems of units. Table 31, Conversion Factors-US Customary Units to SI Metric Units, is very useful for those who wish values in different systems of unit. The study will benefit the commuting public in general, and the transport industry in particular, who make use of these bridges in their daily living. The owners of the bridges and the person responsible for the bridges, academe; fellow engineers and students will also benefit in the study. The study reveals that considering the inventory level, all the three bridges have lower safe truck live load capacity as compared to what was considered in design and as indicated in the supplied reference drawings. Calculated HS 18.75, HS 16.53 and HS 15.167 are for San Diego Bridge, Bagsit Bridge and Amlosong Bridge respectively. Also, it reveals that in the adequacy checking of the cantilever slab, the San Diego Bridge although safe for both in shear at d distance from the support and in bending at the face of the support, fails in shear when the wheel load is directly below the section being considered. The Bagsit Bridge cantilever slab portion as well, is not adequate in both shear location where the wheel load is directly underneath the section considered and at d distance from the support although safe in bending about the face of support ER -