# Studies on Seismic Performance of Precast Concrete Columns with Ground Splice Sleeve
## 1 Introduction  
Precast concrete construction, as a sustainable technology, not only has the advantages of accelerated construction speed, stable and reliable quality, environmental protection, and savings in material, energy, and labor, but also can shorten the development and construction period of residential and non-residential buildings, which is adapted to large-scale and standardized productions [1; 2; 3]. Incorporated with advanced structural control strategies [4; 5; 6; 7; 8; 9; 10; 11], precast concrete structures can perform very well under extreme loads [12; 13; 14; 15]. As the predominant structural type of construction industrialization in China, precast concrete structures take up 77.1% of the total floor area built by construction industrialization [16]. It is widely believed that climate change and global warming are closely associated with carbon emissions, and there is a growing concern about the upward trend in greenhouse gas emissions resulting from building construction [17]. It has been verified that buildings worldwide account for one-third of the global carbon emissions [18], and the residential sector accounts for 17% [19]. To alleviate this situation, it is highly recommended to adopt precast concrete construction. It has been found that the cast-in-situ concrete construction can release 770 kg of carbon dioxide equivalent per cubic meter of concrete, whereas that is 692 kg for precast concrete construction, 10% lower than that of cast-in-situ concrete construction [20]. Based on the specific mix proportion and curing condition, precast concrete under the marine environment can also contribute to a significantreduction in carbon emissions [21]. Since precast concrete construction has been proven to be a more environmentally-friendly and energy-efficient method than cast-in-situ construction, it will play an important role during the development of zero-carbon buildings. The prime issue of the precast concrete structure is the connection between precast components such as beams, columns, slabs and shear walls, etc., that must effectively integrate the individual components to ensure structural safety, serviceability, and durability under various kinds of load conditions [22]. The methods of reinforcement connections for cast-in-situ reinforced concrete structures mainly include bound connections, welded connections, mechanical connections, etc. However, there are some limitations in applying these methods to reinforcement connection of precast members. For example, the mechanical connection requires high installation accuracy of the steel bars, increasing the difficulty of lifting on site. Moreover, since the steel bars are heated during the process of the welded connection, residual stress will be generated in the steel bars. Additionally, due to the small space that the joint of the precast concrete structure occupies, using these conventional reinforcement connection methods would be inconvenient for construction on site. Consequently, reinforcement connection between precast members tends to be one of the critical problems during precast concrete construction. To solve this problem, [PERSON] [23] firstly proposed the grouted splice sleeve (GSS) in the late 1960s, i.e., the ribbed bars were inserted into the metal sleeve, then the grout was poured, and they could work together after the grout was congealed and hardened. Because of the confinement effect exerted by the sleeve, the bond strength of steel bars enhanced significantly, resulting in a shorter bar embedded length [24]. Afterwards, [PERSON] employed this technology to connect the frame columns of Ala Moana which is a 38-story hotel located in Honolulu. In 1983, the grouted splice sleeve was rated as one of the main reinforcement connection technologies by the American Concrete Institute [25]. The long-term use of this reinforcement connection technology has been tested by earthquakes in many countries, such as the United States and Japan, proving that it can be used in seismic and high-rise buildings.