تعيين ضريب بار ديناميكي ديواره دريايي خاك مسلح تحت اثر امواج در حال شكست

Determination of Dynamic Load Factor for Reinforced Earth Seawall under the Breaking Waves

Reinforced earth seawalls are very useful structures to protect and stabilize the shoreline. These structures are also used as quay walls to provide adequate water depth for ship and boat berthing. Free vibration of the wall due to wave impact results in the change of tensile forces in reinforcing members and consequently affects the safety factor of the wall against collapse. So investigation of wave load induced effects on the tensile forces produced in reinforcing members is indispensable. In the present paper, the effects of breaking waves having different periods on the tensile forces produced in steel reinforcing ties of a vertical and smooth reinforced earth seawall are studied. Minikin equations are used to calculate pressures in front of the seawall. Ties are arranged as eight horizontal layers and are divided into four spans. The results showed that there is a critical wave period which leads to maximum increment in tensile force of the ties due to the wave impulse. Amount of this increment is measured for different layers and spans and is expressed as the dynamic load factor. Finally a dynamic load factor is proposed for the considered seawall in order to be used for design purposes.