## 9 Recent Advances in GPC
### GWP Calculation and Assessment  
GWP is the best tool to assess the global warming impact of different gases. Generally, it allows the comparison of emission of any gas with CO\({}_{2}\) emission over a specified time interval. These days, GWP of GPC is a hot topic as it justifies that GPC has less potential to produce global warming than ordinary concrete. It has been reported by Intergovernmental Panel on Climate Change (IPCC) that GPCs containing different binders have substantially less impact of global warming production than OPC concrete [216]. [PERSON] et al. [217] found that the GWP can reduced up to 64% when compared to ordinary concrete due to the environmental sustainable use of NaOH obtained from local solar salt. In Colombia, life cycle assessment (LCA) of natural volcanic pozzolan with 30% slag-based GPC was studied [218]. It was concluded that GPC has 44.7% GWP less than ordinary concrete with the same compressive strength. [PERSON] et al. [219] evaluated the effect of GPC on global warming production and durability characteristics by using practical applications of bridge and retaining wall. The structures made with GPC and reactive powder concrete exhibit less GWP along with more durability characteristics and design life when compared to structures made with OPC concrete. Although GPC has less impact on global warming, it also has some other environmental impacts such as fresh water ecotoxicity, marine toxicity, abiotic depletion, and eutrophication. These impacts, in turn, are influenced by the type of binder and activator selection.  
Researchers [217, 220] made comparison between different binders to assess which aluminosilicate has environmental impact. The environmental impact depends on the internal chemical composition of binder and is influenced by the amount of silicate. For example, the binder that requires high amount of sodium silicate has higher impact of GWP [216, 221]. [PERSON] et al. [216] found that FA and GGBFS has lower CO\({}_{2}\) production and GWP than MK as MK requires more amount of silicates as an activator. However, [PERSON] et al. [221] reported that GPC having 30% MK as a binder has high mechanical strength along with low GWP compared to ordinary concrete. The comparison of binders of GPC along with OPC concrete with respect to environmental impact is presented in Figure 35.  
The calculation of GWP of different types of GPC depends on the various types of techniques and methods involved in different studies. [PERSON] et al. [222] studied the CO\({}_{2}\) emission of GPC by considering all the activities involved in production of GPC from raw material selection to manufacturing including transportation and other energy procedures. It was revealed that GPC has only 9% of CO\({}_{2}\) emission less than ordinary concrete. The steps involved in the calculation of CO\({}_{2}\) emission of GPC and alkaline activator are presented in Figures 36 and 37, respectively.  
Figure 35: Comparison of different GPC containing different binders and OPC concrete [220].  
Hence, it is concluded that the GPC containing any binder has less impact on global warming production than ordinary concrete. However, there exist some other environmental impacts of GPC like marine ecotoxicity, abiotic depletion, eutrophication, or acidification, as presented in Figure 38, which should be considered.  
Figure 37: CO\({}_{2}\) emission resulting from alkaline activator [222].  
Figure 36: CO\({}_{2}\) emission resulting from GPC [222].