37results about How to "High suitability for disaster prevention" patented technology

The invention discloses a debris flow pre-warning method. In view of the shortcoming that the channel-started debris flow critical rainfall threshold calculation method in the prior art needs to be based on long-term debris flow observation data, the invention provides a debris flow pre-warning method. The core of the method is a debris flow start critical value Cr calculation method expressed by debris flow channel topography, geology, and a hydrological factor. According to the method, the Cr value of a pre-warning monitored area is used as a monitored value, and debris flow pre-warning levels are set according to the magnitudes of monitored values; when Cr is less than 0.35, the condition is green and safe; when Cr is larger than or equal to 0.35 and less than or equal to 0.47, a debris flow orange pre-warning is issued; and when Cr is larger than or equal to 0.47, a debris flow red pre-warning is issued. In optimized condition, the rainfall amount of 1h is used as a common monitored value at the same time. The invention also provides a debris flow pre-warning method with an equivalent rainfall R* value as a main monitored value. The method has a reliable principle, the threshold calculation more conforms to debris flow forming mechanism; the threshold calculation is not based on long-term observation data, and has better disaster preventing applicability.

The invention discloses a shallow soil landslide early-warning method in the red-bed area and belongs to the technical field of landslide prevention and control engineering. The method comprises the steps of adopting a landslide mass and a non-landslide mass in the red-bed area as a respondent, measuring a gradients alpha of the landslide mass and the non-landslide mass, an area A of the landslide mass, an upper gradient beta, an upper area Au, a transverse left gradient theta 1, a transverse right gradient theta 2, a transverse left area AL, a transverse right area AR and a terrace area A' on the landslide mass; calculating a gradient factor S, an upper-side factor U, a two-side factor C, a terrain factor T, and a rainfall factor R; calculating a critical value Cr for inducing the shallow soil landslide in the red-bed area and conducting the condition judgment; determining the landslide level, and sending an early-warning signal. According to the technical scheme of the invention, the combined effects of two factors, namely the terrain factor and the rainfall factor, are fully considered to obtain the critical value Cr for inducing the shallow soil landslide mechanism. Therefore, not only the landslide early-warning is high in accuracy, but also the early-warning reaction time is greatly shortened. Therefore, the disaster prevention applicability is improved.

The invention discloses a debris flow outbreak scale calculation method. In view of the shortcoming that the channel-started debris flow outbreak scale calculation method in the prior art needs to be based on long-term debris flow observation data, the invention provides a debris flow outbreak scale calculation method. The core of the method is a debris flow start critical value Cr calculation method expressed by debris flow channel topography, geology, and a hydrological factor, and a debris flow scale calculation method expressed by the critical value Cr. According to the method, the Cr value of a monitored area is firstly used as a monitored value, and when Cr is larger than or equal to 0.35, risk of debris flow occurrence is determined and outbreak scale is further calculated. In optimized condition, the method also uses the rainfall amount of 1h as a common monitored value to determine the risk of debris flow occurrence. The method has a reliable principle, and the threshold calculation more conforms to debris flow forming mechanism; the threshold calculation is not based on long-term observation data, and has better disaster preventing applicability.

The invention discloses a debris flow average speed calculating method and application thereof and belongs to the field of debris flow control engineering. The debris flow average speed calculating method is characterized by comprising the following steps of a, determining debris flow yield stress of tau 0 through field investigation; b, field-measuring debris flow volume weight of rho; C, field-measuring debris flow depth of h; d, calculating non-dimensionalized yield stress of tau through a formula 1; e, field-measuring debris flow surface speed of Vs; f, field-measuring bed roughness of n of debris flow movement; g, calculating debris flow average speed of Vm through a formula 2. The debris flow average speed calculating method takes into full consideration the bed roughness of debris flow movement, the depth and the properties of debris flow, eliminates size effects through non-dimensionalization, facilitates deduction to practical debris flow and has the advantages of being convenient in calculate and high in calculating accuracy. The debris flow average speed calculating method is applicable to large-dimension field practical calculation and can provide crucial reference for assessment and control of debris flow.

The invention discloses a shallow soil landslide early warning method based on a digital topographic map, which belongs to the field of landslide prevention and control engineering, and is characterized by comprising the following steps of: a, connecting a straight line with middle points protruding upwards along a contour line of the topographic map to serve as a middle line; b, determining an intermediate point; c, forming three point groups of plane curvature; d, taking the arithmetic mean value of the gradient as the gradient alpha of the landslide mass; e, according to a terrain DEM data distribution principle, assignments of all points in each grid are the same; f, taking an arithmetic mean value; g, calculating a topographic factor T of the potential landslide mass; h, calculating a rainfall factor R; i, calculating a shallow soil landslide early warning judgment value P; and j, performing early warning according to the shallow soil landslide early warning judgment value P. According to the method, the shallow soil landslide can be pre-warned without a large amount of historical observation data of the landslide, the dangerous landslide body is determined in advance, and the disaster prevention applicability and the pre-warning efficiency are greatly improved.

The invention discloses a method for calculating elasticity modulus of a buffer layer according to the density of the buffer layer. The method is characterized by comprising the following steps that a, earth and stone buffer layer granule characteristic parameters including earth and stone median size D, an earth and stone granule nonuniform coefficient Cu and earth and stone compactness S are measured and calculated, wherein the earth and stone granule nonuniform coefficient Cu is calculated through a formula 1 and includes three levels including uniform level, basic uniform level and nonuniform level, and the levels of the earth and stone granule nonuniform coefficient Cu are calculated through the formula 1; b, the earth and stone compactness S is calculated through a formula 2; c, theearth and stone elasticity modulus M is calculated according to the earth and stone compactness S. The calculating method fully gives consideration to the influence of specific density on the elasticity modulus, is suitable for actual calculation of wild large-sized coarse and large stone block buffer layers, make calculation results accurate and reliable and has better disaster prevention applicability for prevention and decrease of collapse and falling stones.

The invention relates to a method for calculating the impact force of rolling stones, belonging to the fields of collapse, rockfall prevention and control engineering and water conservancy engineering. The impact calculation method of rolling stone of the present invention, comprises the following steps: (1) obtain rolling stone elastic modulus E1, the elastic modulus E2 of impacted object, calculate comprehensive elastic modulus E; (2) estimate rolling stone quality m, rolling stone The moving speed V, the angle θ between the moving direction of the rolling stone and the plane of the impacted object, calculate the impact force F of the rolling stone according to the formula F=0.261(Em2V4)1/3sin0.5θ. The present invention considers the basic principle of dimension harmony for the calculation of impact force, so the calculation method is suitable for large-scale actual calculation in the field, and has higher applicability for disaster prevention and mitigation of landslides and falling rocks.

The invention discloses a calculation method for elastic modulus of a buffer layer. The calculation method is characterized by comprising the following steps: a, earth-rock buffer layer particle characteristic parameters, including earth-rock median diameter D, earth-rock particle nonuniform coefficient Cu and earth-rock buffer layer compactness S, are obtained by calculation, wherein the earth-rock median diameter D refers to particle diameter with weight percentage of 50% in the earth-rock particles, and the unit is mm; the earth-rock particle nonuniform coefficient Cu is calculated by Formula 1; b, the earth-rock type is determined according to the earth-rock median diameter D, and the earth-rock elastic modulus M is calculated. The influence of the specific particle size value of earth-rock on the elastic modulus is fully considered, the calculation method is suitable for actual large-scale calculation of large thick stone buffer layers in the field, the calculation result is accurate and reliable, and the method has higher disaster prevention applicability for preventing and reducing disaster such as collapse and rockfall.