A novel structural detailing for the improvement of seismic and progressive collapse performances of RC frames

Abstract

Summary Earthquake‐induced building collapse and progressive collapse due to accidental local failure of vertical components are the two most common failure modes of reinforced concrete (RC) frame structures. Conventional design methods usually focus on the design requirements of a specific hazard but neglect the interactions between different designs. For example, the progressive collapse design of an RC frame often yields increased reinforcement and flexural strength of the beams. As a result, the seismic design principle of “strong‐column‐weak‐beam” may be violated, which may lead to unfavorable failure modes and weaken the seismic performance. To avoid these adverse effects of the progressive collapse design on the seismic resistance of RC frames, a novel structural detailing is proposed in this study. The proposed detailing technique intends to concurrently improve the seismic and progressive collapse performances of an RC frame by changing the layout of the newly added longitudinal reinforcement against progressive collapse without introducing any additional reinforcement. A six‐story RC frame is used as the prototype building for this investigation. Both cyclic and progressive collapse tests are conducted to validate the performance of the proposed structural detailing. Based on the experimental results, detailed finite element (FE) models of the RC frame with different reinforcement layouts are established. The seismic and progressive collapse resistances of different models are compared based on the incremental dynamic analysis (IDA) and nonlinear dynamic alternate path (AP) methods, respectively. The results indicate that the proposed structural detailing can effectively resolve the conflict between the seismic and progressive collapse designs.

Impact of seismic retrofitting on progressive collapse resistance of RC frame structures

“…Lin et al [51,52] outlined that considering seismic and progressive collapse designs individually may produce an undesirable performance of the structure as well as the waste of construction materials. Therefore, those researchers proposed and experimentally validated a novel design solution for precast RC frame structures based on beam-column connection through unbonded post-tensioning tendons, energy dissipating steel angles, and shear plates.…”

Strengthening of Precast RC Frame to Mitigate Progressive Collapse by Externally Anchored Carbon Fiber Ropes

“…Another problem is avoiding "strong beams and weak columns" while preventing progressive collapse, in other words, giving consideration to seismic performance. Some researchers had proposed new structural detailing (Lin et al [15]) and the use of kinked rebar (Feng et al [16]). Some researchers had proposed a solution where the catenary action (CA) stage is directly strengthened using steel cables anchored by pre-embedded parts (Qiu et al [17]).…”

Progressive Collapse Resistance of Emulative Precast Concrete Frames with Various Reinforcing Details

“…Based on ALP method, extensive tests (Sasani 2008;Sasani and Kropelnicki 2008;Yi et al 2008;Sadek et al 2011;Qian et al2020;Qian and Li 2012a, b;Yu et al 2013;Lew et al 2014;Valipour et al 2015;Shan et al 2016;Lu et al 2017;Lin et al 2019;Yu et al 2020;Deng et al 2020) had been carried out. Sasani (2008) and Sasani and Kropelnicki (2008) carried out pioneer in-situ tests to quantify the dynamic behavior of RC frames subjected to column removal explosively.…”