PCI eLearning Course T110: Preliminary Precast, Prestressed Concrete Design-PCI BDM Ch 6

PCI BDM Ch 6 – Preliminary Design Tables

Pdf Summary

The PCI Bridge Design Manual's Chapter 6 presents an extensive array of preliminary design data for various types of bridge beams, such as AASHTO Box Beams (BII, BIII, BIV), PCI Bulb-Tee Beams (BT-54, BT-63, BT-72), NEXT Beams (D, F), and U-Beams. The document emphasizes multiple aspects required for the design, including concrete transfer strength, number of strands, camber, and various stress factors.<br /><br />Key sections include:<br /><br />1. **AASHTO Box Beams**: Detailed tables provide specs like spacing, slab thickness, number of strands, camber, and stress limits for beam types BII, BIII, and BIV. The data cater to different span lengths and slab thicknesses, indicating their application mainly for bridge spans ranging from 20 to 120 feet.<br /><br />2. **PCI Bulb-Tee Beams**: Tables for BT-54, BT-63, and BT-72 beams offer parameters for designing beams with spans extending to 150 feet. Data includes minimum transfer strength, final camber, and flexural stresses.<br /><br />3. **NEXT Beams**: Design data for NEXT D and F beam types for widths 96” and 144” cover spans from 20 to 80 feet and detail camber, stress limits, and maximum span capabilities.<br /><br />4. **U-Beams**: Specifications for Texas U-40 and U-54, and Washington U66G5 and U78G5, providing comprehensive data for interior and exterior beams. These cater to complex structures, ensuring the beams’ performance across various spans and loads.<br /><br />5. **Stress and Strength Control**: Each beam's control method is well-documented, indicating whether the design is stress-controlled or strength-controlled, ensuring the structural reliability under specified loads.<br /><br />The manual emphasizes a minimum concrete transfer strength of 3.0 ksi (kilo pounds per square inch) across all designs, corroborating the standards outlined in PCI MNL-116 section 5.3.17. This is crucial in preliminary beam design as it impacts the load-bearing capacity and durability.<br /><br />Overall, the chapter serves as a vital reference for engineers and designers, assisting in the accurate specification and design optimization for different types of bridge beams, ensuring safety, reliability, and cost-effectiveness in bridge construction.

Keywords

PCI Bridge Design Manual

AASHTO Box Beams

PCI Bulb-Tee Beams

NEXT Beams

U-Beams

concrete transfer strength

stress control

design optimization

bridge construction

span lengths