*2.3. Precast Construction Process*

The precast construction process of the short-lapped-rebar splices can be divided into five steps: First, a unique wooden mold was made and the metal duct and the embedded rebar were fixed on the mold, as shown in Figure 4a. Then, the spiral hoops were welded on the embedded rebar. The concrete was then poured and the mold was kept for seven days. Figure 4b shows the specimen with the pre-set duct hole after removing the mold. After that, the anchored rebar with two circular plastic locators (Figure 4c) was installed in the duct holes. Note that the first circular locator was used to ensure the designed lapped length, and the second circular locator was used to fix the anchored rebar to the center of the duct. The high-strength grouted mortar was finally poured into the duct holes and cured for 28 days.
