# Efficacy of Fire Protection Techniques on Impact Resistance of Self-Compacting Concrete
## 1 Introduction  
Concrete is extensively employed in infrastructure development on a global scale and has a production rate of around 25 billion tonnes per year, as estimated in 2009 [1]. Compaction is a crucial step in traditional concrete casting [2]. It involves placing the mixture in a mould and compressing it using vibrators to eliminate trapped air and compact the ingredients within the mould to attain the required strength, permeability, and durability for the structural system [3]. Inadequate compaction can lead to reduced stability and inferior-quality concrete, while excessive vibration can negatively impact the overall structural integrity [4]. In-depth research on the passive fire protection of concrete structures was carried out by [PERSON]. Various theories have been put forward to explain the heating rate of concrete at the interface, the analysis of thermal spalling, and the impact of concrete matrix characteristics such as cementitious composite content, initialmoisture content, and aggregate type under elevated temperatures [5]. This approach provides a higher level of scientific accuracy, resulting in more conservative and safer outcomes in relation to fire hazards. Furthermore, it presents advantages in suggesting new design possibilities and promoting the careful and cost-effective application of thermal barriers and fire protection (passive) for concrete [6]. In 1986, a novel form of concrete called self-compacting/consolidating concrete was introduced by Okamura [7]. In contrast to conventional concrete, SCC does not necessitate any vibration or consolidation during the placement process. Due to its inherent weight, SCC effortlessly fills the formwork and smoothly flows around densely arranged reinforcements. SCC is characterised by its remarkable flow properties, such as flowability, passing, and filling ability. The intrinsic fresh characteristics of concrete contribute to the reduction of both construction time and cost. The mixture is enhanced in developing SCC by incorporating SCMs derived from industrial waste products with binder characteristics [8]. The advancement of SCC is motivated by augmenting the fine aggregate and reducing the clinker content. This is achieved using diverse SCMs like FA, GGBFS, Silica, metakaolin, limestone minerals, and other alternatives [9]. This highlights the need for extensive research on SCC development. To analyse the workability of the SCC mixture, the EFNARC 2005 guidelines recommended assessing its flow rate, filling capacity, passing capabilities, and resistance to segregation [10]. To improve the flow properties and reduce segregation in SCC, the inclusion of a superplasticizer (SP) and a viscosity-modifying agent (VMA) can be considered [11]. To mitigate segregation, adding an appropriate quantity of VMA or increasing powder content can effectively maintain the suspension of aggregates within the binder region without impeding the flow [12]. Throughout the lifespan of a structure, concrete can experience significant deterioration in its physical, mechanical, and durability characteristics due to exposure to different loading events and adverse conditions [13]. Fire is one of the significant threats to structures, and it may severely reduce the strength of concrete elements [14]. Beyond 600 \({}^{\circ}\)C, SCC compressive strength decreases significantly [15]. Apart from the decline in compressive strength, the bond strength also experiences degradation beyond a temperature of 700 \({}^{\circ}\)C [16]. The chemical breakdown of cement components in high temperatures is the main cause of property deterioration. This includes factors such as thermal incompatibility, loss of bond in the interfacial transition zone (ITZ), disruption of the gel structure of calcium silicate hydrates (CSH), substantial pore water pressure, and the formation of tensile stress [17]. Currently, there is limited available data on the influence of temperature on the strength characteristics of SCC when mineral admixtures are introduced [18].