BRIDGE-ENGINEERING-MODULE-1_wmark.pdf

BRIDGE ENGINEERING Module #1 PART I - INTRODUCTION BRIDGE  A bridge is a structure that carries traffic over an opening or discon nuity in a landscape such as highway, river, valley and other bodies of water, etc. PRIMARY CONSIDERATIONS IN BRIDGE DESIGN  SAFETY – Safety should not be compr...

BRIDGE ENGINEERING Module #1 PART I - INTRODUCTION BRIDGE  A bridge is a structure that carries traffic over an opening or discon nuity in a landscape such as highway, river, valley and other bodies of water, etc. PRIMARY CONSIDERATIONS IN BRIDGE DESIGN  SAFETY – Safety should not be compromised  FUNCTIONALITY – the func onality of the bridge refers to its intended use  ECONOMICAL – Value Engineering, maximizing resources without compromising the safety, func onality and aesthe cs  AESTHETICS – beauty, geometry WHAT IS BRIDGE ENGINEERING?  is an Engineering discipline branching from Civil Engineering which involves Planning, Design, Construc on, Opera on, Maintenance and Rehabilita on of bridges to ensure safe and effec ve way of transpor ng goods, people and vehicles. STAGES OF BRIDGE ENGINEERING / DESIGN  Planning – Conceptualiza on, Preliminary Site Ocular Inspec on to gather data, conduct studies and feasibili es for bridge schemes.  Design – Preliminary and Detailed o Phases of Design  Preliminary – Selec on of the best concept for bridge scheme/design, ascertain feasibility, and refining budget costs.  Detailed – Finalize all detailed designs and documents to be used for tendering and construc on.   Construc on – Project Implementa on and Execu on o Phases of Construc on  Pre-construc on – Project Ini a on, Bidding and Contrac ng  Actual Construc on/Execu on  Post-construc on – Final Inspec on, Project Turn-over, Project Close-out  Opera on - The opera onal stage refers to the period during which the constructed facility or infrastructure is used for its intended purpose. This involves the management and maintenance of the facility to ensure it operates efficiently and effec vely.  Maintenance – to prolong the usage of the bridge and to slow down deteriora on by iden fying and addressing the issues that contribute to overall infrastructure deteriora on. (e.g. minor repairs)  Rehabilita on – is the act of repairing por ons of an exis ng infrastructure to reset deteriora on process. (e.g. altera ons, major repairs, retrofi ng) PART II – DESIGN CRITERIAS CODES AND SPECIFICATIONS  Refer to the Governing Laws and Department Issuances of implemen ng agencies. (e.g. DPWH) GUIDELINES  DPWH Standard Specifica ons for Highways, Bridges and Airports, 2013  DPWH Bridge Seismic Design Specifica ons, December 2013  Other guidelines provided by interna onal and local organiza ons on specific DPWH projects. May be allowed subject to the minimum requirements of this guideline AASHTO PUBLICATIONS  American Associa on of State Highway and Transporta on Officials (AASHTO) 2012, LRFD Bridge Design Specifica on DESIGN DATA  Topographic / Hydrographic Surveys  Geotechnical Inves ga on o Borehole Loca ons o Borehole Depth o Test on Borehole Samples and Results of Geotechnical Inves ga on  SPT – Standard Penetra on Test  Laboratory Tests – Soil Classifica on, A erberg Limits, Sieve Analysis, Hydrometer Tests, Natural Moisture Content, Specific Gravity, Consolida on test if so soils are encountered, Direct Shear Test or Tri-axial Test.  Summary of Geotechnical Reports – Borehole loca on plan with geographical coordinates and eleva ons, Depth of boreholes, Soil stra graphy at bridge site, Groundwater table eleva on, Soil parameters (e.g. unit weight), Allowable bearing capacity, An cipated se lement, Rock Quality Designa on (RQD), Shear wave velocity, Liquefac on poten al, Recommended Founda on type  Naviga on Data o Observa on and documenta on of marine traffic. o Consulta on with port operators, shipping companies and the Philippine Coast Guard.  Exis ng Bridge Data  Coastal Data o Bridges adjacent to shores or between islands o Tidal waves, storm surges, and tsunami-generated forces  Geohazards o Earthquake phenomena o Volcanic Erup ons  o Storm Surges o Mass flow of debris esp. during major floods o Landslides / mass was ng o Flooding, scour and erosion o Geothermal Ac vity o Climate Change  Environmental Factors o To determine if any local condi ons should be considered in the design of the bridge to minimize environmental damage o To determine if the local environment needs to be taken into account in the design of the bridge; for example, a bridge is located adjacent to the sea would require to be designed for a corrosive marine environment. PART III DESIGN REQUIREMENTS  Bridge Loca on and Alignment – The selec on of favorable river crossing sites should be considered in the preliminary route determina on and feasibility studies to minimize construc on, maintenance and replacement costs.  Bridge Waterway and Length  Span Arrangement  Freeboard or Ver cal Clearance between the Design Flood Level, DFL, and the soffit of the lowest member of the bridge superstructure shall not be less than 1.50 m for rivers carrying debris and 1.00 m for other bridges.  Overflow Type Bridges or Low-level Bridges are usually short-span slab type structures supported on pile substructures with the deck level placed below the 1-year flood level. This type of structure is appropriate for low-  traffic roads where the cost of a conven onal bridge above the flood level cannot be jus fied.  Bridge Deck Drainage – The design of bridge decks shall include the design of bridge deck drainage systems to remove runoff from the bridge deck and divert it to the bridge abutments and discharge it to exis ng stormwater drainage systems or to outlets where stormwater drainage system do not exist. OTHER DESIGN REQUIREMENTS  Clearances o Naviga on o Air clearances o Highway o Underpasses o Tunnels o Through Truss Bridges o Depressed Por on  Curbs and Sidewalks  Traffic Railings – While the primary purpose of traffic railings is to contain and redirect the average vehicle using the structure, considera on should also be given to the following: o Protec on of the occupants of a vehicle in collision with the railing o Protec on of other vehicles or pedestrians on roadways being crossed over o Appearance and freedom of view from passing vehicles