Issue 78

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

more consistent failure behavior. Thus, CMB was used to put the reinforcement bars into the shear wall specimens under cyclic loading.

Property

CMB

Sika

Type

(Kemapoxy 165) Two-component epoxy adhesive mortar

(Sikadur®-31 CF Slow) Two-component thixotropic epoxy adhesive

Compressive strength

800 kg/cm² ( ≈ 78 MPa) 400 kg/cm² ( ≈ 39 MPa)

52 MPa 27 MPa

Flexural strength

Adhesion / bond strength

103 kg/cm² ( ≈ 10 MPa) on concrete

>4 MPa concrete adhesion Slow-curing formulation

Initial setting time

8 h

Full curing / hardness

7 days

7 days

Table 1: Technical properties of the adhesive materials used.

Shear wall specimens (stage II) Four full-scale reinforced concrete shear walls were tested to examine the behavior of newly added shear walls in existing buildings. Each wall had identical dimensions; height of 1500 mm x width of 650 mm x thickness of 120 mm. The walls were anchored to reinforced concrete blocks with the dimensions 1350 mm length x 750 mm width x 550 mm height to simulate an existing foundation condition. A loading head cap (650 mm × 200 mm × 200 mm) was cast on top of each wall for load application. The walls were reinforced with vertical reinforcement of six 16 mm bars (3.08% reinforcement ratio), horizontal reinforcement of 12 mm bars at 167 mm spacing (0.22% reinforcement ratio), in addition to transverse reinforcement of 8 mm closed stirrups with 135° hooks, uniformly spaced. A constant 25 mm concrete cover was maintained for all specimens. Fig.3 shows the specimen details and reinforcement.

(b)

(a)

(e)

(c)

(d)

Figure 3: Reinforcement details of the shear wall specimens: (a) Typical test specimen dimensions and reinforcement, (b) vertical reinforcement anchorage and the loading beam (head cap), (c) embedded length in SWI1, (d) embedded length in SWI2, (e) embedded length in SWI3.

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