Issue 66

M. Q. Hasan et alii, Frattura ed Integrità Strutturale, 66 (2023) 297-310; DOI: 10.3221/IGF-ESIS.66.18

been using natural sand with a maximum particle size of 4.75 millimeters. As shown in Tab. 4, it satisfies the grading requirements of the Iraqi standard specification (I.Q.S No.45-1984). Tab. 5 shows that the maximum diameter of the lightweight coarse aggregate LECA employed in this investigation is 12 mm. This material replaced the coarse aggregate in the LWC. Iraqi standards (I.Q.S. No.45-1984) were used to conduct the necessary testing on this sand.

Figure 1: Specimen dimensions of the present study Sec. (A-A).

Specimen designation

Description

Control SF-100 RF-50 RF-60 RF-70

Referential specimen without CFRP

Strengthened beam with full wrapping CFRP sheets.

Repaired beam with full U-wrapping CFRP sheets and subjected to 50% of damage. Repaired beam with full U-wrapping CFRP sheets and subjected to 60% of damage. Repaired beam with full U-wrapping CFRP sheets and subjected to 70% of damage. Table 1: Beam specimens’ descriptions.

Percentage by weight%

Oxide

Limit of IQS No. 5/ 2019

CaO SiO2

60.37 20.74 5.78 3.48 1.91 1.85 2.44 0.92 0.19

- - - -

Al2O3 Fe2O3 MgO

< 5.0%

SO3

≤ 2.8% for C3A ≥ 3.5%

Loss on Ignition (L.O.I) Lime Saturation Factor (L.S.F) Insoluble residue (I.R) Main compound (Bouge equation) % by weight of cement

< 4.0%

0.66 - 1.02 < 1.5 %

Limit of IQS No. 5/ 2019

-

C3S C2S C3A

41.7 27.4 10.2

- - - -

C4AF

9.9

Table 2: Chemical analysis of cement.

Physical properties

Test result

Limit of IQS No. 5/ 2019

Fineness, Blaine, gm/cm 2 Setting Time: Initial, min Setting Time: Final, min

319 95 410

>230

≥ 45 min ≤ 10hrs

Table 3: Physical analysis of cement.

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