## 3 Applications
### Example Calculation
#### 3.2.2 Stress of PCCP under Combined Loads
\begin{table}
\begin{tabular}{l c} \hline \hline
**Item** & **Value** \\ \hline Thickness of the pipe, \(T\)/m & 0.171 \\ Calculated radius of the pipe, \(r\)/m & 1.0855 \\ Outer diameter of the pipe, \(D_{1}\)/m & 2.342 \\ Combination coefficient of the variable loads, \(\psi_{c}\) & 0.9 \\ The factor of importance for two side-by-side pipelines, \(\gamma_{0}\) & 1 \\ Design value of the maximum bending moment of the pipe at the spring-line, \(M_{max}^{l}/(\text{kN\textminus}\text{m}/\text{m})\) & \(-33.998\) \\ Design value of the maximum axial tension of the pipe at the spring-line, \(N^{l}/(\text{kN}/\text{m})\) & 1111.712 \\ Width of calculated section, \(B\)/m & 1 \\ Ratio of modulus of the strand to the concrete, \(n_{st}\) & 5.83 \\ Ratio of modulus of the cylinder to the concrete, \(n_{y}\) & 5.49 \\ Ratio of modulus of the mortar to the concrete, \(n_{m}\) & 0.68 \\ Conversion area of pipe section (including cylinder, steel strands and the mortar coating), \(A_{n}/\text{m}^{2}\) & 0.1792 \\ Cross sectional area moment of the cross section of the concrete core, mortar, steel cylinder and prestressed steel strand on the inner surface of the pipe wall, \(S_{n}/\text{m}^{3}\) & 0.01496 \\ Cross sectional area of the cylinder for unit pipe length, \(A_{sc}/(\text{m}^{2}/\text{m})\) & 0.0015 \\ Distance from the mandrel to the inner surface of the pipe wall after the conversion, \(y_{0}\) & 0.08347 \\ Distance from the center of the prestressed steel strand to the center of gravity of the pipe wall & 0.06412 \\ Comprehensive adjustment factor for ECP whose diameter is larger than 1600 mm, \(\lambda_{y}\) & 0.9 \\ \hline \hline \end{tabular} Notes: \(T=h_{c}+h_{m}+d_{s}\), \(r=\frac{D_{s}+T}{2}\), \(D_{1}=D_{1}+2T\), \(A_{n}=Bh_{c}+\big{(}n_{y}-B\big{)}By+(n_{st}-n_{m})A_{st}+n_{m}B(T-t)\), \(S_{n}=\frac{B\psi_{c}^{2}}{2}+\big{(}n_{y}-\big{)}By\frac{\big{(}D_{y}-D_{z}-t _{s}\big{)}}{2}+(n_{st}-n_{m})\star A_{st}+n_{m}B(T-h_{c})\big{(}\frac{T-h_{c} }{2}+h_{c}\big{)}\), \(A_{sc}=By_{y},y_{0}=\frac{A_{sc}}{5u},d_{0}=h_{c}+\frac{d_{s}}{2}\times 10^{- 0}-y_{0}\).  
\end{table} 
Table 6: The calculation results of the stress. \begin{table}
\begin{tabular}{c c} \hline \hline
**Item** & **Value** \\ \hline Maximum bending moment of the pipe at the bottom, \(M_{pms}/(\text{kN\textminus}\text{m}/\text{m})\) & 36.316 \\ \hline Maximum bending moment of the pipe at the top, \(M_{pms}^{\prime}/(\text{kN\textminus}\text{m}/\text{m})\) & 23.423 \\ \hline Axial tension of the pipe wall, \(N_{ps}/(\text{kN}/\text{m})\) & 879.255 \\ Elastic resistance moment of the unconverted tension edge of the rectangular section of the pipe & \\ wall, \(W_{p}/\Big{(}\text{m}^{2}/\text{m}\Big{)}\) & 0.00487 \\ \hline Maximum tensile stress at the edge of the pipe at the bottom, \(\sigma_{ss}/\Big{(}\text{N}/\text{mm}^{2}\Big{)}\) & 12.107 \\ \hline Effective prestress of the prestressed steel strands apart from the prestress loss, \(\sigma_{st}^{\prime}/(\text{N}/\text{mm}^{2})\) & 681.06 \\ \hline Influence coefficient of concrete in tension area, \(K\) & 1.2239 \\ \hline Plastic influence coefficient of concrete in tension area, \(\gamma\) & 1.75 \\ \hline \hline \end{tabular} Note: \(K=0.2449\frac{M_{pms}}{\omega_{c}W_{p}f_{ty}}+0.5714\).  
\end{table} 
Table 7: The calculation results of the stress.