# Studies on Seismic Performance of Precast Concrete Columns with Ground Splice Sleeve
## 1 Introduction
Regarding the grouted splice sleeve technology, scholars carried out a lot of research work, trying to find the influence factors that dominate the bond performance of the sleeve as well as their influence rules, which can provide the theoretical foundation for sleeve design. For example, [PERSON] et al. [26] utilized the plain round bars to design four types of grouted sleeves with different parameters and geometries, and based on the axial tension test of these specimens, they found that it is practicable to employ the grouted splice sleeve to connect prefabricated members. [PERSON] et al. [27] conducted the tensile tests of two kinds of grouted splice sleeves, namely welded bar sleeve (WBS) and tapered head sleeve (THS), to study the effect of steel bar embedment lengths and sleeve diameters on the tension capacity of sleeves. [PERSON] et al. [28] investigated the relationship between the interlocking mechanism and bond strength in both the elastic and inelastic regions of the grouted splice sleeve by experiments, and drew a conclusion that the bond strength will be increased if the interlocking mechanism is arranged at the elastic region. Moreover, some researchers put forward the novel grouted splice sleeve. For example, [PERSON] et al. [29] proposed the grout-filled head-slice-sleeve (HSS) and studied the effect of the configuration with or without the head and head size on the bond behavior via experiments. They found that the configuration with a properly sized head can significantly improve the bond strength and the ductility, leading to steel bars' failure at the end. Furthermore, [PERSON] et al. [30] presented a non-proprietary grouted splice sleeve. Compared to the existing products, this kind of sleeve is preferable with low cost and convenient fabrication, and can be compatible with the current production tolerances. In order to strengthen the connection performance of traditional grouted splice sleeves, a series of improvement measures have been taken by researchers. For example, based on the cylindrical steel pipe splice, adding spiral reinforcement [31] and bolts [28], and employing tapered steel pipes [32] and square hollow sections [24] can enhance the confinement pressure and bond stress. Additionally,to improve the durability and corrosion resistance, some scholars adopted aluminum [33] and glass fiber-reinforced polymer [34; 35] instead of steel as the material for making the sleeve. Although there are many studies on grouted splice sleeve technology, the development of reliable connections which have good force-transferring mechanisms and that are easy for construction is still a hot topic in construction industrialization and zero-carbon buildings. This paper studies a grouted splice sleeve which is very convenient for construction. The seismic performance of precast concrete columns using such a connection method is thoroughly experimentally investigated. The grouted splice sleeve connection studied in this paper for steel bars embedded in prefabricated members is shown in Figure 1a. The precast concrete column has a pre-embedded cast iron sleeve in its lower end and the vertical steel bars of the precast concrete column are inserted into the sleeve. During field installation, the steel bars extended from the pedestal are also inserted into the sleeve; then, the grouting material is poured into the sleeve. After the grout becomes congealed and hardened, the stress of the steel bars is transferred by the bond force between the rebar surface and mortar, as well as between the mortar and sleeve wall. Compared with the traditional methods of reinforcement connection, there is no external force and heat exerted on the rebar, which can prevent the rebar from expansion deformation and residual stress. Additionally, the construction operation is convenient, and the requirements on the construction precision, the quality of the construction workers, and the construction environment are not too high.