| Debris flow activities are frequent outbreak in northwest and southwest of our country,it has brought huge losses for people’s lives and property.Due to the Masonry block dam is cheaper,faster,and more durability then other dams,it has been widely applied in debris flows’ governance.But under the effect of different debris flow,dams’ storage capacity have been overflowing.and because the design,siting problems,many dam foundation and abutment have occurred serious damage.If not reinforced, it may occur hazard dam when a large-scale outbreak of debris flow,causing greater risk downstream.This paper puts forward two block dam heightening reinforcement scheme, respectively gravity heightening reinforcement scheme,buttress heightening and strengthening scheme.First of all, through the method of engineering calculation,viewing debris flow load as static load imposed on the dam body to calculate its stability and maximum and minimum pressure stress in dam foundation.By comparing the gravity heightening reinforcement scheme for anti sliding stability of the dam body is better.By comparing the results get Gravity heightening and strengthening programs for the anti-slip better stability of the dam.But the ability to resist overturning buttress heightening reinforcement scheme is better.and its base pressure produce more uniform.By contrast engineering quantity list found buttress programs cost less.Then simply simulate debris flow channel by CFX software case to simplify block dam into a cantilever structure and obtained maximum flow rate 34.26m/s through debris flow dam.And the maximum velocity occurs at the time of fluid through the crest.Due to the effect of crude energy dissipation of the ditch close to the ditch bed rate is almost zero, the upper basin have maximum flow rate.When the fluid reaches block dam,due to the effect of dam the fluid velocity decreases,the direction of change. After the fluid over the crest generated disaster, described block dam in debris reducing flow velocity and weakening the ability of destroy can play.Debris flow make the maximum impact force is 0.6026 Mpa on dam, bottom debris flow impact force is greater than the upper portion. First effect of debris flow dam is not obvious, when 4s debris flow impact effect is stabilized and reaches a maximum.At last,using ANSYS Workbench software,Giving two dam apply overall impact and stone impact force.We got two dams at different times of the shear size of the dam and the combination of surface displacement.The two way of heighteningreinforcement in block stone impact loads,the change of dam displacement is not big.The displacement of the structure is mainly caused by the impact force of debris flow.The overall displacement of two kinds of heightening scheme similar:displacement of dam crest are largest and dam bottom is zero.Under the same load,the dam body approximately 6m the following two kinds of structural displacement almost the same and the counterforted horizontal displacement of 6m above is small then gravity.For the gravity heightening reinforcement scheme,the maximum shear stress occurs in the middle part of the joint surface and Stress distribution range is large,the maximum value is 0.745 MPa.For the counterforted heightening reinforcement scheme,the maximum shear stress is concentrated in the middle part of the column,the maximum value is 0.9807 MPa.This study aimed to debris flow rataining dam heightening reinforcement design provides a safe and reasonable economic scheme.At this stage there is little research in this area.I hope this study can be based on the interests of the people,summarize advantages and disadvantages and put forward a better research plan... |
PDF Full Text Request