Demand continues to increase for bridges with long spans and shallow depths. Due to safety concerns, four-span overpasses are being replaced with two span overpasses to avoid placement of piers near the highway shoulders. In the meantime, the bridge profile is restricted due to existing businesses nearby. Thus, nearly the same superstructure depth must be used for double the span length. This dissertation focuses on topics aiming at providing precast prestressed concrete girders with the shallowest possible depth for a given span. It forms parts of larger projects conducted by the University of Nebraska for the Nebraska Department of Roads and for the Wire Reinforcement Institute. Specifically, the following issues were researched: (1) Use of 0.7 in. diameter Grade 270 ksi strands for pretensioning of precast concrete girders at a strand spacing of 2 inches by 2 inches. This arrangement gives nearly 190 percent of the prestressing with 0.5 in. diameter strands and nearly 135 percent with 0.6 in. strands. The research focuses on the required confinement steel to allow determination of transfer and development lengths according to current procedures in the AASHTO LRFD Bridge Design Specifications for smaller strands. (2) Develop a self consolidating concrete (SCC) mix, using Nebraska aggregates that will allow for a specified design strength at service of 15 ksi and a minimum strength at one day of 10 ksi, representing the demand at the time of release of the prestress to the concrete member. Prior to this study, standard concrete strength prevailing in Nebraska has been 8 ksi at service and 6.5 ksi at release. It was the goal of the research to keep the cost of materials as low as possible but not exceeding 250percubicyard,comparedtotheproprietarymixesthatcostapproximatelyfourtimesthisamount.(3)Useof80ksiweldedwirereinforcement(WWR)astheauxiliaryreinforcementforshear,webendsplittingandflangeconfinement.Thiswouldresultinhigherqualityproduct,lessreinforcementcongestion,about25percentsavingsinthesteelmaterials,andconsiderablesavingsingirderfabricationcosts.Acombinationoftheoreticalandexperimentalworkhasresultedinthefollowingfindings:(1)Ashearfrictionmodelcanbeusedtoestimatetherequiredamountofconfinementofthebottomflange.(2)Areasonablereinforcementdetailisneeded,evenwithveryheavilyprestressedNUIgirderbottomflange,toallowuseofthecurrentmethodsofestimatingstrandstransferanddevelopmentlengths.(3)TwoSCCmixeswithmaterialscostslessthat200 dollars per cubic yard and with the required strengths were able to be developed. The mixes exhibited excellent flowability and predictable engineering properties. (4) Grade 80 WWR was successfully used. Its shear resistance was theoretically predictable. It produced higher capacity than the Ultra High Performance steel fiber concrete demonstrated by the Federal Highway Administration, with much lower costs and conventionally predicable design strength. Advisors: George Morcous, Maher Tadro