Issue 78

S. A. Mustafa et alii, Fracture and Structural Integrity, 78 (2026) 298-314; DOI: 10.3221/IGF-ESIS.78.18

The only variation among the shear wall specimens was the embedment length of the implanted vertical bars into the foundation. While the control wall used the traditional reinforcing technique achieving full development length, as shown in Fig. 4. The implanted-bar walls were constructed with embedment depths of 10 ϕ , 15 ϕ , and 20 ϕ in SWI1, SWI2 and SWI3 respectively. This was to study how anchorage length affects global performance. Fig. 5 shows the preparation of the three shear walls while implanting steel reinforcement bars. Implanting technique for reinforcement The implanted reinforcement used in the shear wall specimens required a careful and controlled installation process to make sure that the bars had enough anchorage inside the existing foundation. The steps of implantation were assigned based on the outcomes of the pull-out tests conducted in Stage I. Drilling method and hole preparation The implanting process began by drilling holes into the concrete foundation at specific locations aligned with the vertical reinforcement layout of the shear walls. A rotary hammer drill was used to maintain geometric uniformity and a constant depth for all implanted bars. The hole diameter was considered according to the results of the pull-out tests; 1.25 times the bar diameter; that achieved the highest pull-out resistance in addition to providing adequate clearance to facilitate effective bonding without the formation of excessive voids. So, this diameter was used for all implanted bars at the base of the shear walls. Before drilling, the required embedment depths; 10Ø, 15Ø, and 20Ø; were carefully measured and marked. The drilling speed and applied pressure were accurately controlled to minimize vibrations and avoid cracking or any damage at the hole edges. After drilling was completed, each hole was visually checked to verify the smoothness of the surface and to ensure that there were no defects that might affect the performance of the implanted bars.

Figure 4: Preparation of Control Shear wall .

Figure 5: Implanting steel reinforcement bars in the three shear walls .

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