Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Civil and Environmental Engineering

First Advisor

Mostafa Tazarv


displacement capacity, mechanical bar splices, moment-resisting frames, pushover analysis, reinforced concrete buildings, seismic performance


Mechanical bar splices, which are commonly referred to as couplers, are currently used in reinforced concrete structures to directly connect steel bars in lieu of conventional lap splicing. With proper detailing, couplers can be utilized to connect precast beams and columns to accelerate the construction. However, the experimental and analytical studies regarding their effect on the performance of RC moment-resisting frames (MRFs) are scarce. Current ACI 318 restricts the use of couplers in plastic hinge regions of special moment-resisting frames (SMRFs). Nevertheless, they can be incorporated at any location of the intermediate and ordinary MRFs. The seismic performance of RC frames incorporating mechanical bar splices in plastic hinge regions was analytically investigated in the present study. Ordinary, intermediate, and special moment-resisting frames (OMRF, IMRF, and SMRF) were included in the study. Three-, six-, and nine-story buildings were designed for each frame type (nine frames in total) according to current ASCE 7 and ACI 318 codes. Modeling methods were proposed for mechanically spliced RC members then the results were verified against large-scale test data from literature. Subsequently, more than 100 pushover analyses were performed on the nine frames by varying the coupler rigid length factor and the coupler length. The results showed that the coupler length, the coupler rigidity, the height and the type of frames affect the displacement capacity of mechanically RC frames. Long and rigid couplers may reduce the displacement capacity of a short SMRF up to 42%. A simple design equation was proposed to quantify the effect of mechanical bar splices on the displacement capacity of RC frames.

Library of Congress Subject Headings

Buildings, Reinforced concrete -- Earthquake effects.
Reinforced concrete construction -- Earthquake effects.
Structural frames.
Reinforcing bars.
Structural design.


Includes bibliographical references



Number of Pages



South Dakota State University


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