阅读说明：本技术 一种边坡地震稳定性判定方法 (Slope earthquake stability determination method ) 是由 田华 董云 于丰泽 周勇 陈龙飞 扈玥昕 朱丹 边鹏 黄方泉 于 2021-01-06 设计创作，主要内容包括：本发明公开了一种边坡地震稳定性判定方法,其包括以下步骤：建立岩质基覆边坡的概化模型、选取研究点、计算地震波到达研究点的应力σ-(ni)、计算下滑剪应力τ-(si)、计算发生剪切破坏的总的下滑力F-滑和抗滑力F-抗、对稳定性进行判定。本方案合理的考虑了滑体自重应力场,控制性结构面的内摩擦角,内聚力以及地震波的透射、反射系数,基岩、覆盖层的物理力学参数,地震波纵波的入射和位移时程等影响因素,来对地震波对滑体的稳定性影响进行判定。有效提升了地震对边坡稳定性影响判定的准确性和可靠性,可为地震滑坡、泥石流的预防和治理工作提供有针对性的依据,并可以实现对边坡稳定状态的实时掌握。(The invention discloses a method for judging the seismic stability of a side slope, which comprises the following steps: establishing a generalized model of the rock-based overburden slope, selecting a research point, and calculating the stress sigma of the seismic waves reaching the research point ni Calculating the glide shear stress tau si Calculating the total gliding force F of the shearing failure Sliding device And a sliding resistance F Resist against And judging the stability. According to the scheme, the influence factors of the sliding body dead weight stress field, the internal friction angle of the controlled structural surface, the cohesive force, the transmission and reflection coefficients of seismic waves, the physical and mechanical parameters of bedrocks and covering layers, the incidence and displacement time range of the seismic waves longitudinal waves and the like are reasonably considered, so that the influence of the seismic waves on the stability of the sliding body is judged. The accuracy and the reliability of judging the influence of the earthquake on the stability of the side slope are effectively improved, a targeted basis can be provided for the prevention and treatment work of the earthquake landslide and the debris flow, and the real-time mastering of the stable state of the side slope can be realized.)

1. A slope seismic stability determination method is characterized by comprising the following steps:

s1: establishing a generalized model of the rock-based covered slope;

s2: uniformly meshing the structural surface of the sliding body in the generalized model;

s3: selecting a certain grid point i on the gridded sliding body structural surface as a research point;

s4: calculating stress sigma on a sliding body structure surface when the seismic wave arrives at the point i by using incident longitudinal waves, reflected longitudinal waves and reflected transverse waves of the seismic wave arriving at the point i_ni；

S5: using stress sigma_niCalculating the glide shear stress τ at point i_si；

S6: repeating the steps S3-S5, and calculating the stress of other points on the structural surface of the sliding body and the sliding shear stress;

s7: calculating the total gliding force F of the sliding body structural surface subjected to shear damage_{Sliding device}And a sliding resistance F_{Resist against}：

Wherein n is the number of selected research points on the slide structure surface, i is the selected research point, and tau_siGlide shear stress for the ith study point, A_i＝0.5(L_i-1+L_i+1) X 1, represents the area represented by the ith study point, wherein L_i-1And L_i+1The side lengths of the ith-l grid point and the i +1 grid point are respectively; sigma_0iRepresents the normal self-gravity at point i;and C_iRespectively, the internal friction angle and the cohesive force at the point i on the structural surface of the slider.

S8: if K ═ F_{Resist against}/F_{Sliding device}≤K₀The sliding body is dangerous; if K ═ F_{Resist against}/F_{Sliding device}>K₀The sliding body is safe, wherein K₀Is the safety coefficient of the side slope;

s9: calculating the total tensile stress F of the sliding body structural surface_{Pulling device}And tensile strength F'_{Resist against}：

Wherein σ_niTensile stress, σ, for i study points_tensioniIndicating the allowable tensile stress of the ith research point;

s10: if K ═ F_{Resist against}/F_{Pulling device}≤K₀The sliding body is dangerous; if K ═ F_{Resist against}/F_{Pulling device}>K₀The sliding body is safe.

2. The slope seismic stability determination method of claim 1, wherein the stress σ is_niComprises the following steps:

wherein λ is₁The number of the components is the Lame constant,in order to make the longitudinal wave incident,in order to reflect the longitudinal wave,in order to reflect the transverse waves, are all wave vectors, andalpha is the reflection angle of longitudinal waves, alpha' is the reflection angle of transverse waves of polarization, mu₁Is the horizontal displacement of the sliding body,are all wave vectors, andσ₀is the normal stress of the initial ground stress field at the point of investigation.

3. The slope seismic stability determination method of claim 2, wherein the horizontal displacement μ₁Comprises the following steps:

4. the slope seismic stability determination method of claim 1, wherein the glideslope shear stress τ_siComprises the following steps:

Technical Field

The invention relates to the technical field of geological activity research, in particular to a method for judging the seismic stability of a side slope.

Background

A number of earthquake disasters have shown that none of the people who die in an earthquake "shake" to death. The fundamental cause of casualties caused by earthquakes is the damage of earthquake motion to engineering structures and the induced secondary disasters, slope instability is one of the most common earthquake secondary disasters, and in mountainous areas or hilly areas, the damage degree sometimes even exceeds the structural damage caused by earthquake motion. Therefore, research work aiming at the stability of the slope earthquake has been one of the key subjects in the fields of geotechnical engineering and engineering earthquake.

The special geographical environment, active geological structure and rapidly developed urbanization construction make the stability problem of the slope earthquake more prominent in China. Therefore, the research on the slope earthquake stability is carried out, and the method has very important theoretical significance and engineering application value for risk evaluation of the slope disaster in China, earthquake-resistant reinforcement design and reduction of loss caused by the landslide disaster.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the judgment method capable of accurately judging the stability of the slope earthquake.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows:

s1: establishing a generalized model of the rock-based covered slope;

s2: uniformly meshing the structural surface of the sliding body in the generalized model;

s3: selecting a certain grid point i on the gridded sliding body structural surface as a research point;

s4: calculating stress sigma on a sliding body structure surface when the seismic wave arrives at the point i by using incident longitudinal waves, reflected longitudinal waves and reflected transverse waves of the seismic wave arriving at the point i_ni；

S5: using stress sigma_niCalculating the glide shear stress τ at point i_si；

S6: repeating the steps S3-S5, and calculating the stress of other points on the structural surface of the sliding body and the sliding shear stress;

s7: calculating the total gliding force F of the sliding body structural surface subjected to shear damage_{Sliding device}And a sliding resistance F_{Resist against}：

Wherein n is the number of selected research points on the slide structure surface, i is the selected research point, and tau_siGlide shear stress for the ith study point, A_i＝0.5(L_i-1+L_i+1) X 1, represents the area represented by the ith study point, wherein L_i-1And L_i+1The side lengths of the ith-l grid point and the i +1 grid point are respectively; sigma_0iRepresents the normal self-gravity at point i;and C_iRespectively, the internal friction angle and the cohesive force at the point i on the structural surface of the slider.

S8: if K ═ F_{Resist against}/F_{Sliding device}≤K₀The sliding body is dangerous; if K ═ F_{Resist against}/F_{Sliding device}>K₀The sliding body is safe, wherein K₀Is the safety coefficient of the side slope;

s9: calculating the total tensile stress F of the sliding body structural surface_{Pulling device}And tensile strength F'_{Resist against}：

Wherein σ_niTensile stress, σ, for i study points_tensioniIndicating the allowable tensile stress of the ith research point;

s10: if K ═ F_{Resist against}/F_{Pulling device}≤K₀The sliding body is dangerous; if K ═ F_{Resist against}/F_{Pulling device}>K₀The sliding body is safe.

The invention has the beneficial effects that: according to the scheme, the influence factors of the sliding body dead weight stress field, the internal friction angle of the controlled structural surface, the cohesive force, the transmission and reflection coefficients of seismic waves, the physical and mechanical parameters of bedrocks and covering layers, the incidence and displacement time range of the seismic waves longitudinal waves and the like are reasonably considered, so that the influence of the seismic waves on the stability of the sliding body is judged. The accuracy and the reliability of judging the influence of the earthquake on the stability of the side slope are effectively improved, a targeted basis can be provided for the prevention and treatment work of the earthquake landslide and the debris flow, and the real-time mastering of the stable state of the side slope can be realized.

Drawings

Fig. 1 is a flowchart of a slope seismic stability determination method.

FIG. 2 is a schematic model diagram of a rocky matrix-covered slope.

FIG. 3 is a reflection and transmission analysis plot of a seismic wave.

Detailed Description

The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.

As shown in fig. 1, the method for determining the seismic stability of the slope according to the scheme comprises the following steps:

s1: establishing a generalized model of the rock-based covered slope;

a large number of earthquake damage investigation results show that the most common slope body structure type with the most instability in an earthquake-stricken area is a base-cover type high-steep slope, and the slopes of the type have a common point: obvious structural surfaces exist in the slope body, the properties of materials on two sides of the slope body are different to a certain degree, and the structural surfaces are main control factors influencing slope collapse. Based on the thought, the invention generalizes the geometric calculation model of the basal-cover type high and steep slope, as shown in FIG. 2.

S2: uniformly meshing the structural surface of the sliding body in the generalized model;

s3: selecting a certain grid point i on the gridded sliding body structural surface as a research point;

when the seismic waves are transmitted to the sliding body structural surface, a large amount of transmission and reflection are generated on the sliding body structural surface, waveform conversion is generated, and various types of seismic waves such as longitudinal waves, transverse waves, Rayleigh waves, love waves and the like are finally formed, wherein the damage to the steep slope caused by the longitudinal waves and the transverse waves is the largest. The mechanism of action at the structural surface of the slider is shown in fig. 3.

S4: calculating stress sigma on a sliding body structure surface when the seismic wave arrives at the point i by using incident longitudinal waves, reflected longitudinal waves and reflected transverse waves of the seismic wave arriving at the point i_ni：

Wherein λ is₁The number of the components is the Lame constant,in order to make the longitudinal wave incident,in order to reflect the longitudinal wave,is a reflected transverse wave; are all wave vectors, andalpha is the reflection angle of longitudinal wave, alpha' is the reflection angle of transverse wave; mu.s₁Is a horizontal displacement of the sliding body, and are all wave vectors, andσ₀is the normal stress of the initial gravitational stress field at point i.

S5: using stress sigma_niCalculating the glide shear stress τ at point i_si：

S6: repeating the steps S3-S5, and calculating the stress of other points on the structural surface of the sliding body and the sliding shear stress;

s7: calculating the total gliding force F of the sliding body structural surface subjected to shear damage_{Sliding device}And a sliding resistance F_{Resist against}：

Wherein n is the number of selected research points on the slide structure surface, i is the selected research point, and tau_siGlide shear stress for the ith study point, A_i＝0.5(L_i-1+L_i+1) X 1, represents the area represented by the ith study point, wherein L_i-1And L_i+1The side lengths of the ith-l grid point and the i +1 grid point are respectively; sigma_0iRepresents the normal self-gravity at point i;and C_iRespectively on the structural surface of the sliding bodyinternal friction angle and cohesion at point i.

S8: if K ═ F_{Resist against}/F_{Sliding device}≤K₀The sliding body is dangerous; if K ═ F_{Resist against}/F_{Sliding device}>K₀The sliding body is safe, wherein K₀For the safety coefficient of the side slope, the safety coefficient K required by the design is utilized₀Judging the safety of the side slope;

s9: calculating the total tensile stress F of the sliding body structural surface_{Pulling device}And tensile strength F'_{Resist against}：

Wherein σ_niTensile stress, σ, for i study points_tensioniIndicating the allowable tensile stress of the ith research point;

s10: if K ═ F_{Resist against}/F_{Pulling device}≤K₀The sliding body is dangerous; if K ═ F_{Resist against}/F_{Pulling device}>K₀The sliding body is safe.

According to the scheme, the influence factors of the dead weight stress field of the sliding body, the internal friction angle and the cohesion of the controlled structural surface, the transmission and reflection coefficients of seismic waves, the physical and mechanical parameters of bedrocks and a covering layer, the incident angle and the displacement time range of the longitudinal waves of the seismic waves and the like are reasonably considered, so that the influence of the seismic waves on the stability of the sliding body is judged. The accuracy and the reliability of judging the influence of the earthquake on the stability of the side slope are effectively improved, a targeted basis can be provided for the prevention and treatment work of the earthquake landslide and the debris flow, and the real-time mastering of the stable state of the side slope can be realized.