Thang Long Bridge, after many years of operation with increasingly large vehicle traffic, resulted in the steel surface of the bridge not ensuring the conditions of stiffness and deflection according to allowable limits. After scientific seminars and experimental research and evaluation, it has been shown that the solution “using ultra-high performance concrete (UHPC) technology with an orthotropic steel deck to form a composite lightweight bridge deck” has been approved. Design selection to repair Thang Long bridge deck. To successfully construct UHPC overlayes in this project, it is necessary to determine technological parameters such as flow, setting time, rheology and shrinkage according to actual construction conditions at the site (temperature and humidity). In addition, other physical and mechanical properties of UHPC must be control and determined such as: compressive strength, tensile strain stress, elastic modulus and drying shrinkage.