Structural Design of Sound Walls with Emphasis on Vehicular Impact

The current process used in Texas to design sound walls was documented by conducting a series of telephone interviews with TxDOT district engineers. The interviews focused on three major topics: the process used to select the sound wall type and material; the structural design procedure; and the major problems encountered. In addition, each of the engineers interviewed was asked to complete a mail survey pertaining to individual sound walls constructed in their district. From these surveys, it was found that the design process and design criteria are not standard in Texas. In addition, TxDOT engineers voiced the need for more research and the development of guidelines for several issues. One of these issues was vehicular impact. For this reason, preliminary research was conducted to study the dynamic response of a prototype mounted sound wall subjected to vehicular impact loads. An analytical procedure was used to assess the adequacy of the current AASHTO 45-kN (10-kip) equivalent static load provisions used to design mounted sound wall systems against vehicular impact. The results of this study indicated that the current static load provisions were inappropriate for mounted sound wall systems because of the dynamic response of the mounted sound wall. Based on these results, example design curves were generated to illustrate how this analytical procedure could be used to develop design guidelines and standard specifications, and recommendations were made for the development of proper procedures for designing mounted sound wall systems against vehicular impact.