## 2 Analysis of the Designing for Fairway Width
### PIANC Standards  
In this study, the Harbor Approach Channels Design Guidelines of the International Association of Water Transportation Facilities (PIANC Rule) were analyzed to examine the appropriateness of the width of the domestic coastal fairways.  
This guideline is used for designing the width of the fairways and channels approaching ports, with the width differing depending on whether it is used for one-way passage or two-way passage. In order to design the fairway width, it is necessary to consider the characteristics of the ships passing through that area of the sea. The basic conditions for designing fairways to ensure the safety of vessels are as follows [21; 22; 23]:  
* Specify the largest vessel using the route;
* Consider the permissible weather conditions in which vessels can navigate the route;
* Specify the traffic capacity that the route can accommodate;
* Note any additional conditions (tugboat support, etc.).  
PIANC's approach channel design guideline sets the basic channel width according to the characteristics of the ship and reflects the influence of wind. The required channel width is added according to the marine environment, air speed, and sea level quality and shape, and cargo type. In addition, the factors applied vary depending on whether the waterway through which the ship passes is one-way or two-way [21].  
As shown in Figure 3, the required channel width of a one-way channel for the bottom width W of the harbor and access channel is calculated using Equation (1):  
\[\text{W}=W_{BM}+\sum W_{i}+W_{BR}+W_{BG}=W_{M}+W_{BR}+W_{BG} \tag{1}\]  
Equation (2) is for the case of a two-way channel:  
\[\text{W}=2W_{BM}+2\sum W_{i}+W_{BR}+W_{BG}+\sum W_{P}=2W_{M}+W_{BR}+\sum W_{P} +W_{BG} \tag{2}\]  
where:  
\(W_{BM}\): Basic maneuvering lane;  
\(\sum W_{i}\): Additional widths to allow for the effects of wind, etc.;  
\(W_{BR}\), \(W_{BG}\): Bank clearance;  
\(\sum W_{P}\): Passing distance between both maneuvering lanes \(W_{M}\).  
Table 1 shows detailed descriptions of the basic navigation channel width and the additional route width of the ship.  
In summary, the Harbor Approach Channel Design Guideline is used for determining the width of the approach channel, as shown in Section 2.2. Table 1 summarizes the criteria used for calculating the width of the approach channel, considering the maneuvering performance, ship speed, and cargo loading according to the type of ship involved. For these factors, when calculating the two-way traffic according to Equation (2), it may appear from 3.8 to 18.6 B.  
\begin{table}
\begin{tabular}{c c c} \hline \hline  & **Width** & **Basic or Additional Width Range** \\ \hline Basic Maneuvering Lane \(W_{BM}\) & 1.3\(\sim\)1.8 B* \\ \hline \multirow{4}{*}{Additional Factor} & Vessel Speed & 0\(\sim\)0.1 B \\ \cline{2-3}  & Wind & 0.1\(\sim\)1.1 B \\ \cline{2-3}  & Current & 0\(\sim\)1.6 B \\ \cline{2-3}  & Wave & 0\(\sim\)1.0 B \\ \cline{2-3}  & Navigation Aids & 0\(\sim\)0.4 B \\ \cline{2-3}  & Bottom surface & 0\(\sim\)0.2 B \\ \cline{2-3}  & Depth & 0\(\sim\)0.4 B \\ \hline Two-Way Traffic & 1.0\(\sim\)2.0 B \\ \hline Bank Clearance & 0\(\sim\)1.3 B \\ \hline \hline \end{tabular}  
* B: Breadth of Target Vessel.  
\end{table}
Table 1: Basic maneuvering lane and additional channel width of PIANC.  
Figure 3: Channel width design standard according to the PIANC guidelines.