Study On The Influence Of New Ecological Brick Slope Protection On The Stability Of River Slope

In the river regulation of China,traditional slope protection often use concrete,masonry,etc These slope protection meet the needs of stability,but ignore the ecological effects that are increasingly valued.At present,China puts forward new requirements when it comes to river regulation.On the basis of following the ecological rules,it can fully play the role of sustainable development of rivers under the safety of rivers.As a measure of river slope treatment,ecological brick slope protection not only satisfies the stability of river slope but also ensures its ecological nature.In this paper,a river channel in Jiangsu Province is taken as the research object,and the application research of new ecological brick slope protection in river bank protection is carried out.The main research of this paper is as follows:(1)Investigate and analyze the types,advantages and disadvantages of existing slope protection technologies,and comprehensively consider the requirements of current slope protection,design two kinds of new ecological brick slope protection,which are plug-in regular hexagonal ecological brick slope protection and plug-in quadrilateral hollow ecological brick slope protection.The above two kinds of ecological brick slope protection have the advantages of large porosity,strong water permeability,large surface roughness and strong integrity.(2)Based on the analysis of the current mold types and materials,the use of plastic molds to produce plug-in regular hexagonal ecological bricks and plug-in quadrilateral hollow ecological bricks.The ecological brick mainly uses P.042.5 grade Portland cement,DM=20mm limestone crushed stone,well-classed fine sand,Grade II fly ash,tap water,naphthalene-based high-efficiency water reducer,etc.Ratio to cement:coarse aggregate:fine aggregate=1:1.43:1.43,and design a reasonable construction process according to the type of ecological brick.(3)Using finite element software to analyze the influence of grid precision on the calculation results,the results show that the error is less than 2.0%when the grid is less than 1.0m;on this basis,the mechanical model of the ecological brick is compared and analyzed according to two kinds of ecological bricks.The change rate of the stable safety factor calculated by the actual contact with the slope surface and the method simplified to the vertical load uniformly arranged on the slope is 1.59%and 1.52%.The calculation results of the two simulation methods are very close,and the simplified surface force is evenly arranged.The way on the slope can effectively reduce the calculation workload,and the results are reasonable.(4)Based on the ABAQUS finite element software,and the strength reduction finite element method,the sensitivity analysis of four factors affecting the stability of the river slope is carried out according to the presence or absence of slope protection measures.The results show that the sensitivity of the four influence factors of river slope stability without slope protection is cohesive force>intemal friction angle>slope coefficient>elastic modulus;the influencing factors of stability of two kinds of ecological brick slope protection in slope protection measures The sensitivity is similar,all are cohesive force>intemal friction angle>slope coefficient>elastic modulus;however,when the ecological brick is laid on the river slope,the influence degree of each factor is reduced compared with the no-slope protection measures.(5)Based on the coupled model of seepage field and stress field,the ABAQUS finite element software is used to study the stability of the river slope under the conditions of no water in the river,the highest water level in the river,the normal water level in the river and the lowest water level in the river.The results show that The ecological brick slope protection can improve the stability safety factor of the river slope under the no-water condition of the river.Under the highest water level of the river,the normal water level of the river and the lowest water level of the river,the safety factor of the slope is gradually reduced with the decrease of the water level of the river.small.At the same time,the stability safety factor of the river slope after the ecological brick slope protection is better than the stability safety coefficient of the soil slope.Taking the seepage effect into consideration,the ecological brick can still improve the slope stability.However,the degree of improvement is smaller than that under anhydrous conditions.In this paper,two new types of ecological brick slope protection are studied from the aspects of design and preparation,river slope stability sensitivity analysis and seepage stability safety analysis,etc.,in order to provide some reference for other types of ecological brick slope protection research methods.