A water-proof of U type rubber water stop and its construction technology that suits for concrete large-deformation of expansion joint is presented in this paper.

On the selection and construction of watertight strip;

From congested drainage of seepage water,untight sealing of watertight strip and expanded rubber water stop and other aspects reasons caused the leakage of circle joint are analyzed,at the same time corresponding seepage prevention measures are proposed,in order to realize good seepage control effects.

The author presents the construction methods of surrounding rock grouting,blind ditch installing,sidewall foundation treatment,geotextile placing,waterproofing membrane placing,drainage material installing,water stop tie installing,secondary lining casting and backfilling grouting on basis of the actual conditions.

A series of experiments on waterproof performance of GINA water stop,which is the most important waterproof measure for connections of pipe sections,were conducted in-cluding stress -compressive deformation test and watertight -ness test etc.

This contradiction was solved by improving the gradation of aggregates,addingUEA concrete expansion agent and RC--1 high effective water--reducing agent,strictlycontrolling the construction quality, installing steel plate water stop in the construction jo.