Stress And Deformation Analysis Of Embedded Concrete Face Rockfill Dam Of Yangqu Hydropower Station

Concrete face rockfill dam is a common dam type with excellent adaptability,which has been used more and more widely in recent years.With the development of modern construction technology and the need of practical engineering construction,the construction demand of super-high concrete face rockfill dam is more and more urgent.Based on some relevant data of Yangqu Hydropower Station,this paper explores the mosaic concrete face rockfill dam with mass concrete at the bottom of ordinary concrete face rockfill dam.The concrete at the bottom of the dam can partly replace the role of conventional face rockfill dam.At the same time,with the increase of the height of mosaic concrete,the total length of face rockfill dam can be greatly reduced.Finally,the stress and deflection of the face slab of the super high concrete face rockfill dam are reduced,and the tensile failure of the face slab is prevented.Through the three-dimensional finite element analysis of the embedded concrete face rockfill dam with different concrete at the bottom,considering comprehensively the displacement and stress values of key dam structures such as vertical displacement of rockfill body,maximum horizontal displacement of upstream and downstream of rockfill body,large principal stress,small principal stress of rockfill body,stress along slope of face slab,deflection along slope of face slab,maximum settlement value of peripheral joints and tension value under two different conditions during completion and impoundment period.The influence of stress and deformation of concrete face rockfill dam is discussed,and the improvement of construction method is discussed in order to effectively improve the stress condition of concrete face and bring a breakthrough for the technical development of super high face rockfill dam.The results show that:Compared with conventional concrete face rockfill dams,the concrete embedded at the bottom of the mosaic concrete face rockfill dam has a positive impact on the reduction of vertical displacement,horizontal upstream displacement,deflection of the face slab,tensile stress and compressive stress of the face slab during the whole construction and storage period,but the appearance of the bottom concrete will significantly increase the settlement value and tension value of the surrounding joints.Compared with the three parameters of concrete height,top width and downstream slope ratio,the concrete height has the greatest influence on the calculation results.With the increase of concrete height,the vertical displacement of rockfill body decreases significantly,and the horizontal upstream displacement of rockfill body decreases significantly,which is conducive to maintaining the overall stability of the dam body.At the same time,with the increase of concrete height,the deflection value,tensile stress value and compressive stress value of the face slab have obviously decreased,which are lower than the allowable values of the tensile stress and compressive stress of the face slab,which is conducive to preventing the failure of the face slab.In addition,slightly reducing the settlement and tension values of the surrounding joints is conducive to controlling the face slab during the impoundment period.Unfavorable seepage control situation with dam body and both sides.Comparing with the influence of different heights of concrete in concrete face rockfill dam,The change of top width and downstream slope ratio of embedded concrete has much less influence on the whole dam body.The influence of top width and downstream slope ratio of embedded concrete on vertical displacement of rockfill body,horizontal displacement of rockfill body and maximum compressive stress of concrete face plate during dam construction period is very small.Even this effect can be neglected.With the increase of top width and downstream slope ratio,the vertical displacement of rockfill body and the deflection of face slab decrease slightly,but at the same time,it will increase the tensile stress of face slab,which is not conducive to the protection of face slab.It is necessary to reinforce the face slab;the settlement value of peripheral joints decreases slightly,but with the increase of downstream slope ratio,the tensile value increases gradually,which requires attention and protection measures.For super-high concrete face rockfill dam,the total length of face slab can be greatly reduced if the concrete with reasonable shape is embedded in the bottom of the dam.Finally,the stress and deflection of the face slab of the super high concrete face rockfill dam are reduced.It is feasible to solve the problem of pulled-out caused by too long slab.However,in this process,special attention should be paid to the problem of increasing the peripheral joints and the problem of engineering cost combined with the actual needs of the project to control mixing.Reasonable structure of concrete block.