2024 ASEE Annual Conference & Exposition

When mixed with water and aggregate, cement is useful in the construction industry due to its strength, versatility, and durability, and additives are often incorporated to improve these properties. This research integrates carbon nanomaterials including graphene and carbon nanotubes (CNTs) into Type 1 cement mortar cubes to investigate their effect on the compressive strength of the resulting concrete. Researchers have previously investigated this topic and the current study seeks to find the optimum amount of carbon nanomaterials to maximize the compressive strength. A water-to-cement (w/c) ratio of 0.45 and sand-to-cement ratio of 2.75 were used to mix fresh cement mortar. The sand was oven-dried and sieved by a No. 10 standard sieve (2 mm). A non-ionic surfactant, Igepal Co-630 combined with ultrasonic dispersion was applied to disperse the carbon nanomaterials before incorporating them into the cement mortar. The tested graphene-to-cement ratios include 0.1%, 0.5%, 1.0%, 1.5%, and 2%. For CNTs, 0.5% and 0.1% of CNTs were tested. Cement mortar cube specimens with dimensions of 2 in × 2 in × 2 in were molded, and all specimens were cured in water at room temperature until compression strength testing at 7, 14, 21, and 28 days. The experimental results show that adding the tested amount of carbon nanomaterials had negative effects on the compressive strength, and the 28-day strength generally decreased as the amount of the content increased, although there were a few enhanced cases at early-stage strength. These controversial results could be derived from the high content of carbon nanomaterials or improper preparation of test samples. Further research will be conducted to conclude the effect of carbon nanomaterials.
This paper describes the experience and outcomes of a non-engineering major who participated in a 10-week Research Experience for Undergraduates (REU) project on civil engineering materials at Marshall University. The main objective of the project was to investigate the effects of carbon nanomaterials on the mechanical properties and durability of cement mortar. The non-engineering major was involved in manufacturing and testing cement mortar cubes with different concentrations of carbon nanotubes and graphene using an ASTM standardized procedure. The paper reflects on the benefits and challenges of conducting quantitative research in an engineering field, such as learning how to use laboratory equipment, analyze data, and write technical reports. The paper also discusses how the interdisciplinary nature of the project helped to broaden the perspective and enhance the problem-solving abilities of the non-engineering major, who applied concepts and methods from forensic anthropology to engineering materials. The paper concludes that the REU project was a valuable opportunity to learn about engineering research and education, despite the inconclusive results that are possibly due to experimental errors, and how the field of anthropology differs from civil engineering.