LESSON 1.pdf

BICOL UNIVERSITY COLLEGE OF ENGINEERING LEGAZPI CITY CE 414 PRESTRESSED CONCRETE DESIGN LESSON 1: INTRODUCTI...

BICOL UNIVERSITY COLLEGE OF ENGINEERING LEGAZPI CITY CE 414 PRESTRESSED CONCRETE DESIGN LESSON 1: INTRODUCTION TO PRESTRESSED CONCRETE DESIGN PREPARED BY: HANA MYKA C. GATON, MSCE INSTRUCTOR HANA MYKA C. GATON, MSCE FACULTY CE 414 – PRESTRESSED CONCRETE DESIGN PRESTRESSED CONCRETE A pre-stressed concrete structure is different from a conventional reinforced concrete structure due to the application of an initial load on the structure prior to its use. HANA MYKA C. GATON, MSCE FACULTY CE 414 – PRESTRESSED CONCRETE DESIGN PRESTRESSED CONCRETE Cracking in tensile region as concrete is weak in tension. Excessive deflection as stiffness decreases due to cracking. Excessive cracking can create durability problems. High strength steel is not used effectively. HANA MYKA C. GATON, MSCE FACULTY CE 414 – PRESTRESSED CONCRETE DESIGN PRESTRESSED CONCRETE Concrete is weak in tension. After cracking, considerable loss in stiffness. Pre-compression substantially increases the external load required to crack the concrete resulting in a member that is strong, tough and stiff. HANA MYKA C. GATON, MSCE FACULTY CE 414 – PRESTRESSED CONCRETE DESIGN PRESTRESSED CONCRETE Control or eliminate tensile stresses in the concrete (cracking) at least up to service load levels. Control or eliminate deflection at some specific load level. Allow the use of high strength steel and concrete. HANA MYKA C. GATON, MSCE FACULTY CE 414 – PRESTRESSED CONCRETE DESIGN PRESTRESSED CONCRETE Pre-stressed concrete also have higher shear capacity compared to the ordinary reinforced concrete. Pre-stressed concrete can improve the flexural capacity in columns (for typical design region where ku