Effects of postcast connection locations on the seismic performance of precast concrete frame joints

Abstract

Summary For the precast structure with postcast connections, the location of the connection is usually the midspan of the beam, joint core, and beam end. However, the postcast connections located at the midspan of the beam or the joint core would increase the difficulty of construction because of the large dimension of the precast components or reinforcement congestion at joint core, respectively. A connection located at the beam end could decrease the seismic performance the energy dissipation mechanism being disturbed. To balance the requirements on the transportation, construction, and seismic performance, the connection is proposed to be located at one plastic hinge length from the beam end. A quasi‐static test was conducted on three 6 m × 3 m beam‐column joints, including two precast joints and a monolithic joint. The results show that the joint with connections located outside the plastic hinge zone had good seismic performance. When the connection located at the beam end, the ductility, strength, and energy dissipation reduced 8%, 10%, and 30%, respectively. To optimize the postcast location, finite element analysis was conducted and 2h was suggested for the postcast location according to the analysis results.

Service Life Prediction of Precast Concrete Structures Exposed to Chloride Environment

“…A more reasonable mode is ductile flexural failure, which is consistent with the results of some experimental investigations [17,61,62]. Despite the uneven stiffness introduced by grout sleeve and connection interface, there is little difference between the bearing capacities of precast and monolithic joints [17,63], so the bearing capacity models proposed for corroded cast in situ components are used to evaluate the flexural performance of PC structures. When calculating flexural capacity, the influence of axial force is nonnegligible, especially for columns, so a moment, axial force curve (M-N curve), is necessary.…”

Experimental Study on a Novel Dry Connection for a Precast Concrete Beam-To-Column Joint

“…Precast concrete architecture is a new type of architecture that combines precast construction technology with sustainable technology. Compared with cast-in-place concrete structures, precast ones are advantageous in terms of less resource consumption, more rapid construction, better quality control and less field wet operation [1][2][3]. Currently, the precast concrete structure system is greatly developed and popularized in China.…”

“…Many research results show that the precast joint with the wet connection has a similar seismic performance to the monolithic joint with good energy dissipation and bearing capacity [6][7][8][9]. In addition, the wet connection does not require high production accuracy for its components, so it has convenience in assembling [2]. However, the advantages of precast structures are not fully utilized in the wet connection due to numerous on-site activities, such as casting wet joints and the grouting of ducts and connections [10].…”

“…Dry connection does not require cast-in-place, which greatly improves the construction efficiency, and avoids the drawback of environmental pollution. Dry connection can be mainly classified as (1) welded connection [11,12], (2) prestressed connection [13][14][15][16][17][18], and (3) bolted connection [11,[19][20][21][22][23][24][25].…”

“…Besides, the energy dissipation is comparable to those of monolithic structures [11,12]. However, the quality of welded connections relies heavily on the skill of the welders, and is difficult to be guaranteed [2].…”