## 2 Applicable Nanotechnology Solutions to Road Maintenance
### Repair of Potholes Using Pre-Prepared GE-NANO NME Pothole Repair Kit  
In cases where damage in terms of potholes have already occurred, the surfacing can quickly be fixed with an anionic NME gravel mix pothole repair kit (GE-NANO Pothole Repair kit) (Geonano Technologies (Pty) Ltd., 18 Davies road, Wychwood, Germiston, 1401, South Africa) (Figure 12). Due to the organofunctional modification of the anionic NME mix, the pothole mix will dry within an hour. The use of an anionic NME pothole mix (GE-NANO Pothole Repair Kit) is performed at a fraction of the costs of traditional cold mix, providing a hydrophobic (water-repellent) restored surfacing. The tested Unconfined Compressive Strengths (UCS) and the Indirect Tensile Strengths (ITS) performed according to the recommended rapid curing process in a dry and wet state [16] are shown in Table 4. Before the repair of potholes, the hole should first be cleaned of any loose material as per normal procedure. The pothole must be dry, and for potholes requiring more than one bag to fill, the exposed material within the pothole should be treated with the application of a clear-seal (diluted NPNS) or by \"painting\" the cleaned pothole with some spare anionic NME binder. The formation of potholes is usually an indication of a severely compromised surfacing in terms of its ability to prevent water from entering the pavement structure. It follows, that the fixing of individual potholes will not be a solution to restore the integrity of the surfacing, and potholes will continue to develop along the length and width of the road. In order to restore the integrity of a road surface, the filling of potholes should be performed as one element in a process to repair and restore the integrity of the surfacing and prevent water ingress into the base layer and the continued formation of potholes. As per the standard in the industry, anionic NME binder pothole kits (GE-NANO Pothole Repair Kit) used in this demonstration and tests are prepared in 25 kg bags for ease of use on site. Due to the low viscosity of the binder, no problems of application at temperatures above freezing is experienced. These anionic NME binder pothole kits can be produced at a cost of about US$ 3.00/25 kg (including packaging) at an established place of manufacturing. \begin{table}
\begin{tabular}{l c c c c} \hline \hline \multicolumn{1}{c}{**UCS (MPa)**} & \multicolumn{2}{c}{\
\begin{tabular}{c} **Material** \\ **Classification** \\ \end{tabular} } & \multicolumn{2}{c}{**ITS (kPa)**} & \multicolumn{2}{c}{
\begin{tabular}{c} **Material** \\ **Classification** \\ \end{tabular} } \\ \hline
**UCS (dry)** & 4.4 & NME1 & **ITS (dry)** & 350 & NME1 \\ \hline
**UCS (wet)** & 4.3 & NME1 & **ITS (wet)** & 320 & NME1 \\ \hline RCS \({}^{*}\) & 98\% & NME1 & **RTS \({}^{**}\)** & 91\% & NME1 \\ \hline \hline \end{tabular}  
* RCS, Retained Compressive Strength [16]. \({}^{**}\) RTS, Retained Tensile Strength [16].  
\end{table} 
Table 4: Unconfined Compressive Strength (UCS) and Indirect Tensile Strength (ITS) tests performed on an NME binder prepared GE-NANO Pothole Repair Kit—evaluated against the criteria used to evaluate the stabilisation of material using a material compatible NME stabilising agent [16]. \begin{table}
\begin{tabular}{l c c} \hline \hline
**Pendulum Test Results** & **Control (No Seal)** & **With Clear-Seal Application** \\ \hline
**Test Point 1** & 100 & 110 \\ \hline
**Test Point 2** & 110 & 100 \\ \hline
**Test Point 3** & 110 & 95 \\ \hline
**Test Point 4** & 90 & 100 \\ \hline
**Test Point 5** & 95 & 90 \\ \hline
**Total (Average)** & **101** & **99** \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Sidd-resistance measurements using the British Pendulum testing device before and after the application of the clear seal (GE-NANO clear seal).