Study On Dynamic Characteristics Of Different Dam Structures Of High Asphalt Concrete Core Dam

Asphalt concrete core wall dam is widely used in harsh areas with high altitude conditions such as northwest and northeast China due to its ability to adapt to complex geological conditions.Under the same geological conditions,the higher the height of the dam,the greater the economic effect.Due to the effect of water pressure,the core wall will be deflected and deformed downstream,and the width of the valley will remain unchanged,and tensile stress will be generated at the abutment of the core wall.However,as the height increases,the tensile stress at the shoulder of the traditional straight-wall straight dam will gradually increase.When the tensile stress exceeds the tensile strength of the asphalt concrete,the core wall will produce tensile cracks,which will lead to dam failure.In order to reduce the tensile stress,we propose to design the traditional straight-wall straight dam into a curved wall directly to the core wall.However,the engineering geological conditions in the western part of China are complex,with frequent earthquakes and high intensity.If earthquake damage occurs in high dams in these areas,serious consequences will result.Therefore,this paper uses ABAQUS and Geo Studio finite element software to study the height of different dams(90m,50m,130m,150m)and the curvature of different core walls(6.7 × 10-5 m-1?9.6 × 10-5 m-1?1.1×110-1 m-1)The variation of stress,deformation and seismic capacity of three-dimensional finite element static,dynamic core wall and dam body of asphalt concrete core wall dam.The main research results of this paper are:(1)The finite element study of straight wall dams with different dam eights(50?m,90,130m,150m)is carried out to study the influence of dam height on the core wall and dam body.The results show that as the dam height increases,the compressive stress on the core wall and the dam body increases gradually,but the tensile stress at the dam shoulder also increases.During the earthquake,the acceleration and displacement in all directions increase with the height of the dam.At the same time,the dam height has a great influence on the displacement and acceleration of the Shun River.The vertical displacement and acceleration are second,and the axial displacement and acceleration of the dam are the least affected.(2)Curved wall straight dam with different core wall curvatures(6.7 × 10-5 m-1?9.6 ×10-5 m-1?1.1 × 10-4 m-1)Instead of a straight wall straight dam.The results show that the curved core wall can effectively reduce the tensile stress at the abutment,and the curvature of the core wall is larger,the tensile stress is smaller,and the compressive stress is increased slightly.During the earthquake,the curved core wall is stronger than the straight core wall,but the curvature and seismic capacity are not necessarily proportional.The finite value should be finite.When the wall curvature is taken as the limit,its resistance to earthquake is the strongest.When the curvature is greater than or less than the limit,its resistance to earthquakes is reduced.The limit may be between 9.6 × 10-5 M1 to 1.1 × 10-4 m-1.And the curvature of the core wall has a greater influence on the acceleration,and has less influence on the dynamic displacement.(3)By analyzing the height of the dam body(90m,50m,130m,150m),the straight dam and the curvature of different core walls(6.7 × 10-5 m-1?9.6 × 10-5 m-1?1.1 × 10-4 m-1).The minimum of the dam slope of the curved core wall under different seismic wave peaks(0.38g,0.55g,0.7g,0.85g)The safety factor time history curve shows that the peak acceleration of the dam's ultimate seismic capacity is 0.70g?0.85g,but the height of different dams is different from the curvature of different core walls.When the height is higher or the curvature of the wall is smaller,its The limit peak acceleration is closer to 0.70g.