We prove that the entropy for an $L^$\infty$$-solution to a scalar conservation laws with continuous initial data is concentrated on a countably $1$-rectifiable set. To prove this result we introduce the notion of Lagrangian representation of the solution and give regularity estimates on the solution.

}, keywords = {concentration, Conservation laws, entropy solutions, Lagrangian representation, shocks}, issn = {1937-1632}, doi = {10.3934/dcdss.2016.9.73}, url = {http://aimsciences.org//article/id/ce4eb91e-9553-4e8d-8c4c-868f07a315ae}, author = {Stefano Bianchini and Elio Marconi} }