Through analysis about the polyethylene pipes in hydrostatic strength testing,the formula of axial,radial and hoop stress were inferred.

A calculation formula of limit to growth length when grout body cracked is deduced from the hoop stress of wholly bonded prestressed cable grout body,which is concurred between the hoop tension stress is created by pretension and the uniformly corrosion expansion force by cable body.

Adopting the general finite element computation software to analyze symmetry Y-type reinforced concrete bifurcation pipe in Hydropower Station, this paper has calculated annular stress and distortion distribution of reinforced concrete bifurcation pipe, and analyzed the influence that indide hydraulic pressure has on bifurcation pipe wall rock.

Based on cylindrical shell theory, the calculating formulas of circumferential pressures, circumferential stresses and pressure influence height on chimney tube generated by radial pressure are obtained.

And the circumferential stresses of the diversion waterway s 8 cross-sections which are along the water flow,the normal stresses around the gate slot,the circumferential stresses aroun.