a method for the waterproofing of joints and / or cracks in the upstream face of dams , other hydraulic works and concrete or masonry structures . a waterproofing membrane includes a strip of elastically yielding synthetic material that is fastened to the surface to be protected along the whole joint and / or crack . prior to positioning the waterproofing membrane , sliding elements are positioned onto the surface to support the membrane . a protection and sliding substrate is properly fastened independently from the waterproofing membrane so that the waterproofing membrane is allowed to freely elongate and follow the movements of the joint and / or the crack while maintaining a water tightening condition .