Expeditious urbanization and population rise around the globe has fostered the need of speedy and efficient construction, thus generating immense pressure on the construction industry to introduce an efficacious construction technique. The issue can be addressed by precast technology, which is advantageous over conventional monolithic construction in regards to speed, safety, and quality control along with reduced construction cost on mass scale production. However, precast reinforced concrete (RC) buildings have experienced severe damage during the past earthquakes, attributed to seismic behavior of connections between components. Thus, it is of utmost importance to improve the joint connection details and deploy seismic resisting features in precast buildings, such as provision of precast shear walls. Researchers across the world have performed extensive experimental studies to evaluate the response of precast RC walls under lateral loading. This paper reviews on general concepts, codal provisions, precast RC wall connections, review of experimental findings, and effect of post‐tensioning on precast RC walls.

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Vibration based techniques are gaining popularity for damage detection, precise localization and damage quantification. These techniques involve recording of the vibration signatures and their analysis for temporal and spectral characteristics to arrive at conclusive statement. Among different damage identification techniques, most of the algorithms are model based approaches and lacks standardization and accuracy. In this paper, feasibility of using output-only model-free wavelet based techniques for damage identification of 6-storied scaled reinforced concrete (RC) building is studied. The vibration signals at different floor levels of the RC building were acquired using wireless accelerometers. The vibration measurements were carried out for different cases i.e. bare frame and varying mass at different floors. The signal discontinuity of the acceleration response of RC building was extracted using complex continuous Gaussian wavelet transformation and analysed. The results show that wavelet coefficients are directly influenced by the change in physical properties of structure and are able to detect damage to a reasonable extent.

In precast construction, standardized concrete elements are manufactured in a controlled environment followed by onsite installations. One such precast system is 3S building system (Strength, Safety, and Speed), which consists of RCC hollow columns with notches; RCC solid beams ("T" shape/"L" shape/Square Shape), RCC Stair flights, RCC shear walls, and Autoclave Aerated Concrete (AAC) or RCC precast slab. The current study focuses on seismic performance of this system, where a full-scale two storey, "3S" precast RC building, was subjected to quasi-static lateral loading. The experimental results show that the structure responded within elastic range at Life Safety (LS) performance level with minimal damage to the joints. The results are further compared to an analytical model in SAP2000 subjected to pushover analysis. Both the experimental and analytical results were found to be in agreement. Therefore, it is inferred that the 3S building system can perform satisfactorily under seismic loads.

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