ACI 550.7-19 (IN-LB) PDF Download

ACI 550.7-19 (IN-LB) is a standard that provides procedures for designing special precast concrete shear walls that are post-tensioned with unbonded tendons. These walls are intended for use in regions with high seismic activity and in structures that require high seismic design categories. The main objective of this standard is to ensure that these special precast shear walls can withstand major seismic events with minimal damage and negligible permanent displacements.

Unlike conventional monolithic shear walls, these precast shear walls do not meet the prescriptive requirements of Chapter 18 of ACI 318-14. Therefore, their acceptance requires evidence from experimental tests and analysis to demonstrate that they have strength and toughness equivalent to or greater than monolithic reinforced concrete walls that comply with the prescriptive requirements.

This standard provides design requirements and a commentary to guide engineers in demonstrating the strength and toughness of the unbonded post-tensioned precast walls through analysis. It outlines the procedures for designing these walls to meet or exceed the performance of special reinforced concrete monolithic walls.