# Multifunctional Graphene-Concrete Composites: Performance and Mechanisms
## 1 Introduction  
Concrete is recognized for its durability, low cost, and favorable structural properties, making it a predominant building material worldwide. It is extensively utilized in infrastructure, commercial buildings, and residential construction. However, the continuous growth of the concrete industry has led to an increasing demand for cement and aggregates, resulting in heightened CO\({}_{2}\) emissions. Consequently, the development of high-performance, multifunctional concrete is essential for advancing a sustainable and resource-efficient construction industry [1, 2, 3, 4]. Currently, extensive research has been conducted on the mechanical properties of concrete incorporating steel slag, fibers, and other materials. These studies provide innovative insights into the application of novel concrete in modern construction [5; 6]. [PERSON] et al. investigated the effects of various mixtures of high-toughness polypropylene (HTPP) fiber on the flexural strength, compressive strength, and stress-strain behavior of ceramic concrete. They analyzed the action mechanism of HTTP fiber reinforcement in ceramic concrete using scanning electron microscopy. This study provides important theoretical support for the structural analysis and design of this type of concrete [7]. [PERSON] et al. incorporated steel slag material into concrete as a substitute for coarse aggregate and investigated the relationship between the compressive strength of steel slag concrete and age. The results indicated that the compressive strength of the concrete increased rapidly within the first 7 days before gradually slowing down [8]. Steel-fiber-reinforced concrete (SFRC) is widely recognized for its excellent properties. To investigate the influence of steel fibers on the mechanical properties of concrete, steel fibers were incorporated into beams to evaluate the compressive strength of the concrete [9]. [PERSON] et al. conducted a comprehensive evaluation of the compressive strength and flexural strength of concrete incorporating various lengths and diameters of steel fibers, as well as different water-cement ratios. Both compressive and flexural strengths were found to be significantly improved. Additionally, they proposed an analytical model to describe the stress-strain relationship under compression in steel-fiber-reinforced concrete (SFRC) [10]. [PERSON] et al. partially replaced cement with waste glass powder (WGP) and examined the effects of varying proportions of WGP on the compressive strength, splitting tensile strength, and flexural strength of concrete. They determined the optimal WGP ratio and developed empirical equations to predict these mechanical properties of the concrete [11]. Currently, the rapid economic development is driving a continual increase in total energy consumption, with energy use related to heating and operating buildings becoming the third largest contributor to social energy consumption [12; 13]. Currently, energy savings in buildings can primarily be achieved through innovations in building materials and structures, as well as the comprehensive utilization of renewable energy sources. As a renewable energy option, solar energy is both clean and efficient. By integrating solar energy storage into building envelope structures, it is possible to significantly reduce energy consumption and meet the energy demands of buildings [14; 15; 16]. However, solar energy is intermittent and unpredictable, making it unavailable throughout the day. Therefore, the efficient conversion of solar energy and effective energy storage solutions are essential [17]. Therefore, the photothermal performance of novel concrete materials has become a research hotspot. Photothermal materials, which exhibit exceptional light- and heat-absorption capabilities, enable the efficient conversion of solar energy into thermal energy. This process not only diminishes reliance on conventional energy sources but also contributes to a reduction in greenhouse gas emissions.