Mechanical Properties of Laminated Veneer Lumber Beams Strengthened with CFRP Sheets

Abstract

This paper presents the results of the static work analysis of laminated veneer lumber (LVL) beams strengthened with carbon fabric sheets (CFRP). Tested specimens were 45mm wide, 100 mm high, and 1700 mm long. Two types of strengthening arrangements were assumed as follows: 1. One layer of sheet bonded to the bottom face; 2. U-shape half-wrapped reinforcement; both sides wrapped to half of the height of the cross-section. The reinforcement ratios were 0.22% and 0.72%, respectively. In both cases, the FRP reinforcement was bonded along the entire span of the element by means of epoxy resin. The reinforcement of the elements resulted in an increase in the bending strength by 30% and 35%, respectively, as well as an increase in the global modulus of elasticity in bending greater than 20% for both configurations (in comparison to the reference elements).

Strengthening of Bent LVL Beams with Near-Surface Mounted (NSM) FRP Reinforcement

“…The maximum force values, the 133 determined parameters and the basic statistical analysis are summarized in Tables 4 and 5. the time interval recommended by the standard [16]. The beams E2, E4 and E5 were destroyed in a For all the reference beams, the time taken to achieve the maximum total load is reached within the time interval recommended by the standard [16]. The beams E2, E4 and E5 were destroyed in a time slightly surpassing this area (Figure 4).…”

“…An increase in the ductility can be observed for the E-series components-curvature of the curves in the final phase of the tests (Figure 3). For all the reference beams, the time taken to achieve the maximum total load is reached within the time interval recommended by the standard [16]. The beams E2, E4 and E5 were destroyed in a time slightly surpassing this area (Figure 4).…”

“…understood as the sum of the forces recorded by the computer set in each of the actuators with respect 132 to the test duration and the deflection at the center of the beam span. The maximum force values, the 133 determined parameters and the basic statistical analysis are summarized in Tables 4 and 5. the time interval recommended by the standard [16]. The beams E2, E4 and E5 were destroyed in a For all the reference beams, the time taken to achieve the maximum total load is reached within the time interval recommended by the standard [16].…”

“…The test results are a continuation of the work on reinforcing LVL beams with fiber-reinforced polymer materials. In other works [16,17], issues of reinforcing laboratory scale specimens by gluing aramid, carbon and glass sheets to the external surfaces of the components were raised.…”

Repair of local damages to precast prestressed slab elements at a parking garage

“…It included strengthening of double T beams with FRP wraps (figure 5) and protecting the inverted T girder with steel angles (figure 6). Strengthening with FRP wraps became a recognized solution for strengthening of reinforced concrete and other types of structures [5][6][7]. However, since FRP wraps application in strengthening is a comparatively new solution, the design specifications regarding them still undergo development.…”