NEHRP Clearinghouse

Title
Strengthening Methodology for Lightly Reinforced Concrete Frames-II. Recommended Calculation Techniques for the Design of Infill Walls.
File
PB94187648.pdf
Author(s)
Phan, L. T.; Todd, D. R.; Lew, H. S.
Source
May 1994, 35 p.
Identifying Number(s)
NISTIR-5421
Abstract
Empirical equations were developed for estimations of ultimate lateral shear strength, story drift ratio at ultimate load, and ductility factor of existing lightly reinforced concrete frames (bare frames), existing monolithic shear walls, and reinforced concrete frames strengthened either by cast-in-place infilled walls or by single or multiple precast concrete panels. These equations were derived based on experimental results of many independently conducted test programs. Estimations of the ultimate shear stress, ultimate story drift ratio (story drift at ultimate load divided by story height), and ductility factor using the empirical equations compared favorably with the experimental results. The estimations confirm many observations made independently in individual test programs. The empirical expressions also provide benchmark values or ranges for these important parameters and thus provide a useful means for quick estimations of seismic capacity of bare, monolithic, and strengthened lightly reinforced concrete frames.
Keywords
Dynamic response; Reinforcement (Structures); Earthquake engineering; Loads (Forces); Frames; Reinforced concrete; Infilled walls; Displacement; Concrete structures; Shear strength; Dynamic structural analysis