Engineering Commons^™

Characterization And Structural Shear Behavior Of Recycled Aggregate Concrete Beams Reinforced With Basalt Fibers And Basalt Bars, Shahrukh Shoaib Ul Haq

Dissertations

Recycling construction waste material offers a sustainable solution to the problem of disposing of concrete construction and demolition waste. The use of basalt fibers (BF) and basalt fiber-reinforced polymer (BFRP) reinforcing bars in concrete structures made of recycled concrete aggregate (RCA) would prolong their service life and reduce the maintenance cost. This research aims to investigate the potential use of BF, RCA, and BFRP reinforcing bars to produce sustainable and steel-free structural concrete. The study consisted of material characterization testing, numerical simulation, and large-scale beam testing.
Material characterization tests were performed on normal-strength concrete (NSC) and high-strength concrete (HSC). The …

Strengthening Of Concrete Deep Beams Using Carbon Fabric Reinforced Cementitious/Geopolymeric Matrix, Nour Mohamed Muhsen Khir Allah

Theses

This research aimed to examine the effectiveness of using carbon fabric-reinforced matrix (C-FRM) composites to improve the shear response of reinforced concrete (RC) deep beams. Ten RC deep beams with a/h of 1.6 were tested, where a is the shear span and his is the beam depth. Test parameters included the presence of internal shear reinforcement (no shear reinforcement and minimum shear reinforcement), number of C-FRM composite layers (one and two layers), angle of inclination of the second layer of CFRM (90o and 0o with respect to the longitudinal direction of the beam), and type of matrix (cementitious and geopolymer). …

Bond Behavior Of Fabric Reinforced Geopolymeric Matrix-Concrete Joints, Feras Farid Abu Obaida

Civil and Environmental Theses

This research aimed to examine the potential use of a geopolymeric matrix as a sustainable alternative to commercial mortars in carbon fabric-reinforced matrix composites. Single-lap shear tests were conducted to examine the bond behavior at the fabric-matrix interface. Test parameters included the type of matrix (geopolymeric and cementitious matrices), the type of fabric (unidirectional and bidirectional) and the bonded length (50 to 300 mm). The geopolymeric matrix was a blend of fly ash/ground granulated blast furnace slag activated by an alkaline solution of sodium silicate and sodium hydroxide. The bond behavior of the geopolymeric-matrix specimens was characterized and compared to …

Shear Strengthening Of Reinforced Concrete Beams Using Textile-Reinforced Mortar, Oluwafunmilayo Morenike Awani

Theses

The effectiveness of using carbon textile-reinforced mortar as an innovative technique to improve the shear response of reinforced concrete beams has been investigated. The research comprised double-shear bond testing on bond behavior of textile-reinforced mortar, large-scale beam testing on shear response of reinforced concrete beams strengthened with textile-reinforced mortar, and nonlinear finite element modeling of the tested beam specimens. Test variables of the double-shear bond testing were the matrix type, and width/length of the bonded area, whereas for the large-scale beam testing, the variables included the number of textile-reinforced mortar layers, matrix type, and amount of internal stirrups. Results of …

Retrofitting Of Shear-Deficient Reinforced Concrete T-Girders With Composite-Based Systems, Alaa Ahmad Ata Maali

Theses

This research examines the viability of using different composite-based systems to upgrade the shear resistance of shear-deficient reinforced concrete T-girders. The research comprised experimental testing and analytical investigation. Test parameters included the retrofitting system; externally-bonded carbon fiber-reinforced polymer (EB-CFRP) laminates with or without a mechanical end anchorage (MA) and embedded through depth glass fiber-reinforced (ETD-GFRP) rebars; amount of internal stirrups; no stirrups, limited amount of stirrups with spacing s₁ = 0.6d, higher amount of stirrups with spacing s₂ = 0.375d; and initial shear damage prior to retrofitting; no damage, pre-cracking, and pre-failure.

The shear …

Strengthening Of Reinforced Concrete Beams Pre-Damaged In Shear, Yousef Mohammed Bachar Chekfeh

Theses

Repair and strengthening of existing reinforced concrete (RC) structures has increased drastically in recent years. Shear reinforcement in RC beams is typically of a small bar diameter, and hence any shear-damage would result in a severe safety hazard and a catastrophic mode of failure especially under extreme loading events. The present work was initiated to the effectiveness of different composite strengthening systems; namely externally bonded carbon fiber reinforced polymer (EB-CFRP), and near surface mounted glass fiber reinforced polymer (NSM-GFRP) to prolong the functional service life of RC beams pre-damaged in shear. It comprised experimental testing and analytical investigation.

The experimental …