The TriStar also has titanium tear strips (fail-safe strips) for added strength.
The L-1011's titanium tear strips (fail-safe strips) did not add strength. Their purpous was to prevent a crack from propagrating through two frame bays or 40 inches. Test showed that the fuselage skin was fail safe with up to a 40 inch long crack.
The titaninum strips were bonded to the skin, if they became disbonded, they did not have to be reattached except in the lower portion (bilge area) of the fuselage.