Fibers Reinforced Composites

Lab # 6

Prepared By:

Eduardo Hernandez

CE 335 – Civil Engineering Materials

October 14, 2021

Objectives

The lab’s goal was to investigate the variation in Elastic Modulus of fiber reinforced composites

with different fiber orientations, as well as to measure Elastic Modulus in flexure.

Experimental Procedure

As illustrated in Fig. 1, the lab contains 5 samples of FRP (Continuous Fiber Reinforced

Polymer) with different fiber orientation angles that will be flexed by an applied load. The loads

were applied in four steps (500g, 750g, 1000g, and 2500g), and the deflection at the sample’s

midway was measured in millimeters using a digital gauge placed beneath the sample.

Fig. 1: Example of a specimen being tested on the digital gauge.

The dimensions of each sample were recorded independently, then each sample was placed

over the testing equipment and exposed to the load while the flex data was collected. The

testing apparatus consisted of two supports spaced 150mm apart on which the sample was

placed, a loading plate on which the weights were placed, and a digital gauge to record the

deflection values. A Load vs. Deflection plot was used to illustrate the data for each sample, and

a regression line was fitted to describe the data, as shown in Fig. 2. The moment of inertia for

each individual specimen was also estimated using the dimensions of the samples. Making use

of the

Discussion of the Results

As illustrated in Figs. 1, 2, 3, and 4, the collected data for the five samples was plotted on a single

Load vs. Deflection plot, and each was fitted with a regression model to estimate their specific

slope.

y = 46.973x + 0.0112

0.0000

2.0000

4.0000

6.0000

8.0000

10.0000

12.0000

14.0000

0 0.05 0.1 0.15 0.2 0.25 0.3

Load (N)

Load Vs Deflection θ = 0º