*3.3. Strain Variation of Rebar*

Strain variations in the anchored rebar along the longitudinal direction at different loading levels are depicted in Figure 8. Here, *x*<sup>i</sup> is the distance from the loading end to the anchorage end. Clearly, the strain of the anchored rebar increases from the loading end to the anchorage end, as shown in Figure 8. A similar phenomenon is also found in Kang's test [22], as shown in Figure 8.

According to Xu's method [23], the average bond stress *τ<sup>i</sup>* between the grout mortar and the anchored rebar can be established from the strain of the anchored rebar. Figure 9 illustrates the distribution of the average bond stress *τ*<sup>i</sup> along the longitudinal direction at different loading levels. Compared with the stress distribution of the anchored rebar in conventional specimens shown in Xu's test [23], the stress of the anchored rebar in the short-lapped-rebar splices is distributed symmetrically along the longitudinal direction, as shown in Figure 9. In contrast, the stress of the anchored rebar in conventional specimens is relatively high at the anchorage end. In addition, the bond stress of the short-lapped-rebar splices is much higher than that of the conventional specimens shown in Xu's test [23] and GB50010-2010 [19].

**Figure 8.** Strain variations of *x*i–average strain at different loading levels [22].

**Figure 9.** Strain distributions of *x*i*τ*<sup>i</sup> under different loading levels [23].
