CN101246217A - Dangerous rock falling calamity early warning instrument and method thereof - Google Patents

Abstract

The invention discloses a dangerous rock masses collapse damage pre-alarming instrument and pre-alarming method thereof, the stress acquisition device of pre-alarming instrument includes at least two stress detectors, each stress detector is respectively connected to the signal input end of the data real time analyzing and processing device through stress signal transmission line; the data real time analyzing and processing device process stress signal transmitted from stress detector, calculates the stability coefficient of collapse source dangerous rock masses, and determines safety state of tested object, when the safety state of the tested object comes up to the pre-alarming level, the data real time analyzing and processing device sends control signal to the alarming device, the alarming device sends various alarm signals; the invention is used for real time monitoring dangerous rock collapse and safety states of important bridge, tunnel, underground project and other constructions, and conducts a real-time pre-alarm of disaster.

Description

Dangerous rock falling calamity early-warning apparatus and method for early warning thereof

Technical field

The present invention relates to disaster monitoring source of early warning field, especially relate to a kind of dangerous rock falling calamity early-warning apparatus and method for early warning thereof.

Background technology

Because China is the country on mountain more than, the crag avalanche is seriously threatening the safety of China's hillman life, the main line of communication and urban construction as a kind of main hazards.For example, only Chongqing is domestic in the reservoir area of Three Gorges just exists place surplus the crag 4000 that collapse hazard easily takes place, and amounts to more than 50000 crag body, the safety of life and property that is threatening more than 80 ten thousand people; Xichang, Sichuan Province to Lugu Lake tourism highway is along the line have 2000 surplus place's collapse hazard; Collapse hazard point in place's surplus Sichuan-Tibet highway Sichuan section exists 3200.China causes the nearly 1000 people injures and deaths because of collapse hazard every year, and the collapse hazard that occurred in stockaded village, the east of Sichuan Gaoyang, national highway 318 line Hubei as 2007 is buried passenger vehicle, causes full car 36 people's death then and there! The control of crag collapse hazard more and more is subjected to government and the people's of all circles close attention, and still, the basis of China's crag research at present is extremely weak, and research lacks systematicness, control lacks specific aim, validity.Artificial on-site land survey is still leaned in strick precaution early warning work to the crag collapse hazard at present basically, then survey data is taken back the indoor processing of studying, and provides evaluation result at last and feeds back to relevant department.Yet, crag often develops quite rapid by unstability to the process that avalanche takes place, the collection of personal monitoring's delay of response, data does not possess real-time, does not have the effect of effective strick precaution collapse hazard in most cases, and the tragedy that the avalanche of crag unstability causes calamity happens occasionally.Equally, in the production and construction practice, need too its sensitive part is carried out monitoring early warning and safety for buildings such as important bridge, tunnel, house and structures, to avoid causing irremediable loss for people's lives and properties because of disaster such as toppling over or cave in.Therefore, the monitoring and the real-time early warning of various avalanche disasters are badly in need of a kind of monitoring and warning equipment that possesses real-time and validity.

Summary of the invention

In view of this, the purpose of this invention is to provide a kind of dangerous rock falling calamity early-warning apparatus, improve the real-time and the validity of crag collapse hazard early warning.

For reaching above purpose, dangerous rock falling calamity early-warning apparatus of the present invention by the following technical solutions:

Dangerous rock falling calamity early-warning apparatus of the present invention, comprise stress harvester, data in real time APU and warning device, described data in real time APU comprises signal input part, mode setting device and data processing controller, is preset with data in real time analysis and processing program, crag body tensile strength K in the data processing controller _ICConnect segment length a with crag body master control architecture face ₀Described stress harvester comprises that quantity is no less than two taseometer, and taseometer is laid in crag body tension zone, avalanche source, and taseometer is connected to the signal input part of described data in real time APU respectively by the stress signal line; The data in real time analysis and processing program of described data processing controller is according to the stress signal of signal input part, mode state signal and the crag body tensile strength K that mode setting device is set _IC, crag body master control architecture face connects segment length a ₀Judge the residing safe condition of tested crag body, when different warning level that tested crag body safe condition reaches that the data in real time analysis and processing program sets, the data in real time APU sends different early warning control signals and gives described warning device, and described warning device sends different caution signals according to the early warning control signal.

Further, described mode setting device comprises the manual input mode selector switch, manually imports button, lithology preference pattern switch and lithology selection key;

Further, the quantity of described taseometer is 10, taseometer is laid in crag body tension zone, avalanche source respectively, 5 taseometer test tensions, all the other 5 taseometer test shear stress, described data in real time analyzing and processing is provided with 10 signal input parts, and signal input part is corresponding one by one with taseometer;

Further, the signal input part of described stress signal line and described data in real time APU adopts the socket connected mode, when the stress signal line when socket is extracted, warning device directly sends corresponding alerting signal;

Further, described taseometer requires: the stress test scope is not less than 100Mpa, and the stress criterion error is not more than 10PPm, and operating ambient temperature is between-10 ℃～80 ℃.

Further, described warning device comprises loudspeaker and warning light.

Another object of the present invention provides the method that adopts described dangerous rock falling calamity early-warning apparatus to carry out the dangerous rock falling calamity early warning, may further comprise the steps:

A. determine crag body tensile strength K _IC

Embody a sampling from avalanche source crag, the fracture toughness of test crag body intact rock, with this fracture toughness as crag body tensile strength K _IC

Perhaps with the existing statistical value of the relevant tensile strength of sandstone, limestone, muddy limestone, grouan, Irish touchstone and marble respectively as various lithology crag body tensile strength K _IC

With crag body tensile strength K _ICDefault to the storage space of data processing controller;

B. measure and determine that avalanche source crag body master control architecture face connects segment length a ₀, and with a ₀Default to the storage space of data processing controller;

C. lay taseometer in avalanche source crag body tension zone, select the mode of operation of dangerous rock falling calamity early-warning apparatus according to mode setting device;

D. the data in real time APU is gathered tensile stress sigma that taseometer transmits and the numerical value of shear stress τ in real time;

E. the data in real time APU is by following formula calculating strength variable K ₁, K ₂And k ₀:

$K_1=1.12\mathrm{\σ}\sqrt{{\mathrm{\πa}}_0},$

$K_2=1.12\mathrm{\τ}\sqrt{{\mathrm{\πa}}_0},$

k ₀＝(K ₁/K ₂) ²；

F. the data in real time APU calculates avalanche source crag body rock rift direction angle θ by following formula ₀:

${\mathrm{\θ}}_0=\arccos \left[\frac{3+\sqrt{k_0^2+8k_0}}{k_0+9}\right];$

G. the data in real time APU calculates k by following formula ₁～k ₈Totally eight parameters:

$k_1=\cos \frac{{\mathrm{\θ}}_0}{2},$ $k_2=\frac{1}{2}[(3\cos {\mathrm{\θ}}_0-1)\sin \frac{{\mathrm{\θ}}_0}{2}-3\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2}],$ $k_3=k_1^2+k_7^2$

$k_4=k_6^2+k_8^2,$ k ₅＝2(k ₁k ₆+k ₇k ₈)， $k_6=\frac{1}{2}[3\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2}+(3\cos {\mathrm{\θ}}_0-1)\sin \frac{{\mathrm{\θ}}_0}{2}]$

$k_7=\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2},$ $k_8=(3\cos {\mathrm{\θ}}_0-1)\cos \frac{{\mathrm{\θ}}_0}{2};$

H. the data in real time APU calculates avalanche source crag body breaking factor K by following formula _e:

$K_e=\frac{1}{2}[k_1{K}_1+k_2{K}_2+\sqrt{k_3{K}_1^2+k_4{K}_2^2+k_5{K}_1{K}_2}];$

I. the data in real time APU is calculated the stability factor of avalanche source crag body by following formula:

$F_s=\frac{K_{\mathrm{IC}}}{K_e};$

J. the data in real time APU is according to determining the residing safe condition of tested crag body by following judgement and sending corresponding early warning control signal and give warning device:

Work as F _s〉=1.20 o'clock, tested avalanche source crag body totally was in a safe condition;

As 1.05≤F _s＜1.20 o'clock, tested avalanche source crag body totally was in the basic security state;

As 0.98≤F _s＜1.05 o'clock, tested avalanche source crag body totally was in critical collapse state;

Work as F _s＜0.98 o'clock, tested avalanche source crag body totally was in collapse state.

Further, in the c step, lay 5 taseometer test tensions, simultaneously, data in real time APU in the d step is gathered the mean value of stress data of 3 taseometers of stress numerical maximum in real time, as the numerical value of the real-time tensile stress sigma of avalanche source tension zone rock; In the c step, also lay 5 taseometer test shear stress in addition, simultaneously, the data in real time APU in the d step is got the wherein mean value of the stress data of 3 taseometers of stress numerical maximum, as the numerical value of the real-time shear stress τ of avalanche source tension zone rock.

The invention has the beneficial effects as follows: the present invention measures crag body tension and shear stress numerical value in real time by the scene and goes out a rational crag body stability factor through what computing drew, whether fall into rational safe condition scope by the value of judging this stability factor, thereby determine the safe condition of tested crag body, the present invention meets the genesis mechanism of the disaster of crag body avalanche more to the analyzing and processing of crag body stress data, thereby can improve the accuracy that crag body safe condition is estimated, thereby improved the validity of crag avalanche early warning; Data in real time analysis and processing program of the present invention combines with dangerous rock falling calamity early-warning apparatus hardware device of the present invention, can be in real time from the collection in worksite stress data, carry out analyzing and processing by the data processing controller analyzing and processing, judge the safe condition of monitored crag body quickly and accurately, and send corresponding safe condition caution signal, thereby reach the real-time that improves the early warning of crag collapse hazard, improve the purpose of the validity of crag collapse hazard early warning.

Description of drawings

Fig. 1 is the electric schematic block diagram of dangerous rock falling calamity early-warning apparatus of the present invention;

Fig. 2 is the synoptic diagram of the mainframe box of dangerous rock falling calamity early-warning apparatus of the present invention;

Embodiment

Below in conjunction with drawings and Examples early-warning apparatus of the present invention is further described, as shown in Figure 1 and Figure 2:

Fig. 1 is the electric schematic block diagram of dangerous rock falling calamity early-warning apparatus of the present invention, and dangerous rock falling calamity early-warning apparatus of the present invention comprises stress harvester, data in real time APU and warning device three parts; Wherein, stress harvester adopts taseometer 1, the data in real time APU comprises signal input part 2, mode setting device 4 and data processing controller 3, warning device adopts loudspeaker 5 and warning light 6, wherein, signal input part 2, mode setting device 4, data processing controller 3, loudspeaker 5, warning light 6 and one are in order to include in a mainframe box 8 for data processing controller 3 and warning device direct current power source supplying power 7.Be preset with data in real time analysis and processing program, crag body tensile strength K in the data processing controller 3 _ICConnect segment length a with crag body master control architecture face ₀Described stress harvester comprises 10 taseometers, and taseometer is laid in crag body tension zone, avalanche source, and taseometer is connected to the signal input part 2 of described data in real time APU respectively by the stress signal line; The data in real time analysis and processing program of described data processing controller 3 is according to the stress signal of signal input part 2, mode state signal and the crag body tensile strength K that mode setting device 4 is set _IC, crag body master control architecture face connects segment length a ₀Judge the residing safe condition of tested crag body, when different warning level that tested crag body safe condition reaches that the data in real time analysis and processing program sets, the data in real time APU sends different alarm control signals and comprises loudspeaker 5 and warning light 6 for described warning device, and loudspeaker 5 sends different caution signals with warning light 6 according to alarm control signal.The data processing controller 3 of present embodiment adopts single-chip microcomputer.

Figure 2 shows that the synoptic diagram of the mainframe box 8 of dangerous rock falling calamity early-warning apparatus of the present invention, when the dangerous rock falling calamity early-warning apparatus of present embodiment is used to monitor the crag avalanche of side, traffic main artery, mainframe box 8 is placed in the stable position contiguous with the crag body, 10 taseometers 1 are laid in crag body tension zone, avalanche source respectively, 5 test tensions, all the other 5 test shear stress, described data in real time analyzing and processing is provided with 10 signal input parts 2, each signal input part 2 adopts the jack form, each signal input part 2 connects a jack, all jacks concentrate the side that is arranged on mainframe box 8 to form socket 19, signal input part is corresponding one by one with taseometer, and each signal input part 2 links to each other with taseometer 1 by socket 19.The specification of taseometer 1: the stress test scope is not less than 100Mpa, and the stress criterion error is not more than 10PPm, and operating ambient temperature is between-10 ℃～80 ℃.The signal input part of stress signal line and described data in real time APU adopts socket 19 to carry out, and when the stress signal line was extracted from socket 19, warning device directly sent corresponding alerting signal according to the instruction of data processing controller 3; Described mode setting device 4 comprises manual input mode selector switch 11, manually imports button 13, lithology preference pattern switch 10 and lithology selection key 15, also is provided with lithology display window 14 and tensile strength display window 12 in addition.The front of mainframe box 8 also is provided with power switch 9, power light 16, and warning light 6 is arranged on 17 places, signal lamp position, mainframe box 8 front, and loudspeaker 5 is arranged on mainframe box 8 side loudspeakers 18 places, position are set.

When making early-warning apparatus of the present invention, to preset crag body tensile strength K in the data processing controller 3 _IC, crag body master control architecture face connects segment length a ₀With the data in real time analysis and processing program.

At first to determine crag body tensile strength K _IC

Embody a sampling from avalanche source crag, by Fatigue Cracking Test test crag body intact rock, with this fracture toughness as crag body tensile strength K _ICPerhaps, with the existing statistical value of the relevant tensile strength of sandstone, limestone, muddy limestone, grouan, Irish touchstone and marble respectively as various lithology crag body tensile strength K _IC

Then, adopt transit or tape measure field measurement to determine that avalanche source crag body master control architecture face connects segment length a ₀

Determine crag body tensile strength K _ICConnect segment length a with crag body master control architecture face ₀After, with K _ICAnd a ₀Default in the storage unit of data processing controller 3.Then, the data in real time analysis and processing program of organized data processing controller, and this program is defaulted in the storage unit of data processing controller 3, after data processing controller powered up, guiding moved this program automatically.

Above-mentioned data in real time analysis and processing program comprises following analyzing and processing process:

A. tensile stress sigma and shear stress τ signal that real-time received signal input end 2 transmits; Get the wherein mean value of the stress data of three taseometers 3 of stress numerical maximum, as the real-time tensile stress sigma of avalanche source tension zone rock; Get the wherein mean value of the stress data of three taseometers 3 of stress numerical maximum, as the real-time shear stress τ of avalanche source tension zone rock;

B. read a that defaults in data processing controller 3 storage unit ₀Numerical value, and by following formula calculating strength variable K ₁, K ₂And k ₀:

$K_1=1.12\mathrm{\σ}\sqrt{{\mathrm{\πa}}_0},$

$K_2=1.12\mathrm{\τ}\sqrt{{\mathrm{\πa}}_0},$

k ₀＝(K ₁/K ₂) ²；

C. calculate avalanche source crag body rock rift direction angle θ by following formula ₀:

${\mathrm{\θ}}_0=\arccos \left[\frac{3+\sqrt{k_0^2+8k_0}}{k_0+9}\right];$

D. calculate k by following formula ₁～k ₈Totally eight parameters:

$k_1=\cos \frac{{\mathrm{\θ}}_0}{2},$ $k_2=\frac{1}{2}[(3\cos {\mathrm{\θ}}_0-1)\sin \frac{{\mathrm{\θ}}_0}{2}-3\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2}],$ $k_3=k_1^2+k_7^2$

$k_4=k_6^2+k_8^2,$

k ₅＝2(k ₁k ₆+k ₇k ₈)， $k_6=\frac{1}{2}[3\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2}+(3\cos {\mathrm{\θ}}_0-1)\sin \frac{{\mathrm{\θ}}_0}{2}]$

$k_7=\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2},$ $k_8=(3\cos {\mathrm{\θ}}_0-1)\cos \frac{{\mathrm{\θ}}_0}{2};$

E. calculate avalanche source crag body breaking factor K by following formula _e:

$K_e=\frac{1}{2}[k_1{K}_1+k_2{K}_2+\sqrt{k_3{K}_1^2+k_4{K}_2^2+k_5{K}_1{K}_2}];$

F. according to the different mode of the setting of mode setting device 4, read the K that defaults in data processing controller 3 storage unit _ICNumerical value, and calculate the stability factor F of avalanche source crag body by following formula _s:

$F_s=\frac{K_{\mathrm{IC}}}{K_e};$

G. according to the stability factor F of avalanche source crag body _sThe real-time numerical value situation of falling following different numerical ranges judge the residing safe condition of tested crag body:

Work as F _s〉=1.20 o'clock, tested avalanche source crag body totally was in a safe condition;

As 1.05≤F _s＜1.20 o'clock, tested avalanche source crag body totally was in the basic security state;

As 0.98≤F _s＜1.05 o'clock, tested avalanche source crag body totally was in critical collapse state;

Work as F _s＜0.98 o'clock, tested avalanche source crag body totally was in collapse state;

H. according to the judgement of g step to sending different steering orders, control described loudspeaker 5 and send different warning signal signals with warning light 6;

I. when signal input part 2 signal deletions, warning device directly sends corresponding alerting signal.

When using the dangerous rock falling calamity early-warning apparatus of present embodiment, mainframe box 8 to be placed in the stable position contiguous with the crag body, adopt the strain rosette method that 10 taseometers 1 are laid in crag body tension zone, avalanche source respectively, 5 test tensions, all the other 5 test shear stress.

Dangerous rock falling calamity early-warning apparatus of the present invention and method for early warning thereof can also be used for the monitoring early warning and safety of buildings sensitive parts such as bridge, house, tunnel, guarantee the people life property safety, possess suitable practicality equally; But, determine tensile strength K _ICThe time, need to experimentize according to the concrete buildings material that constitutes.

Explanation is at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, the modification that those of ordinary skills make technical scheme of the present invention or be equal to replacement, only otherwise break away from the spirit and scope of technical solution of the present invention, all should be encompassed in the middle of the claim scope of the present invention.

Claims (8)

1. dangerous rock falling calamity early-warning apparatus, comprise stress harvester, data in real time APU and warning device, it is characterized in that: described data in real time APU comprises signal input part, mode setting device and data processing controller, is preset with data in real time analysis and processing program, crag body tensile strength K in this data processing controller _ICConnect segment length a with crag body master control architecture face ₀Described stress harvester comprises that quantity is no less than two taseometer, and taseometer is laid in crag body tension zone, avalanche source, and taseometer is connected to the signal input part of described data in real time APU respectively by the stress signal line; The data in real time analysis and processing program of described data processing controller is according to the stress signal of signal input part, mode state signal and the crag body tensile strength K that mode setting device is set _IC, crag body master control architecture face connects segment length a ₀Judge the residing safe condition of tested crag body, when different warning level that tested crag body safe condition reaches that the data in real time analysis and processing program sets, the data in real time APU sends different early warning control signals and gives described warning device, and described warning device sends different caution signals according to the early warning control signal.

2. dangerous rock falling calamity early-warning apparatus according to claim 1 is characterised in that: described mode setting device comprises the manual input mode selector switch, manually imports button, lithology preference pattern switch and lithology selection key.

3. dangerous rock falling calamity early-warning apparatus according to claim 2, be characterised in that: the quantity of described taseometer is 10, taseometer is laid in crag body tension zone, avalanche source respectively, 5 taseometer test tensions, all the other 5 taseometer test shear stress, described data in real time analyzing and processing is provided with 10 signal input parts, and signal input part is corresponding one by one with taseometer.

4. dangerous rock falling calamity early-warning apparatus according to claim 3, be characterised in that: the signal input part of described stress signal line and described data in real time APU adopts the socket connected mode, when the stress signal line when socket is extracted, warning device directly sends corresponding alerting signal.

5. dangerous rock falling calamity early-warning apparatus according to claim 4 is characterised in that: described taseometer requires: the stress test scope is not less than 100Mpa, and the stress criterion error is not more than 10PPm, and operating ambient temperature is between-10 ℃～80 ℃.

6. dangerous rock falling calamity early-warning apparatus according to claim 5 is characterised in that: described warning device comprises loudspeaker and warning light.

7. adopt described dangerous rock falling calamity early-warning apparatus to carry out the method for dangerous rock falling calamity early warning, may further comprise the steps:

A. determine crag body tensile strength K _IC

Embody a sampling from avalanche source crag, the fracture toughness of test crag body intact rock, with this fracture toughness as crag body tensile strength K _IC

Perhaps with the existing statistical value of the relevant tensile strength of sandstone, limestone, muddy limestone, grouan, Irish touchstone and marble respectively as various lithology crag body tensile strength K _IC

With crag body tensile strength K _ICDefault to the storage space of data processing controller;

B. measure and determine that avalanche source crag body master control architecture face connects segment length a ₀, and with a ₀Default to the storage space of data processing controller;

C. lay taseometer in avalanche source crag body tension zone, select the mode of operation of dangerous rock falling calamity early-warning apparatus according to mode setting device;

D. the data in real time APU is gathered tensile stress sigma that taseometer transmits and the numerical value of shear stress τ in real time;

E. the data in real time APU is by following formula calculating strength variable K ₁, K ₂And k ₀:

$K_1=1.12\mathrm{\σ}\sqrt{{\mathrm{\πa}}_0},$

$K_2=1.12\mathrm{\τ}\sqrt{{\mathrm{\πa}}_0},$

k ₀＝(K ₁/K ₂) ²；

F. the data in real time APU calculates avalanche source crag body rock rift direction angle θ by following formula ₀:

${\mathrm{\θ}}_0=\arccos \left[\frac{3+\sqrt{k_0^2+8k_0}}{k_0+9}\right];$

G. the data in real time APU calculates k by following formula ₁～k ₈Totally eight parameters:

$k_1=\cos \frac{{\mathrm{\θ}}_0}{2},$ $k_2=\frac{1}{2}[(3\cos {\mathrm{\θ}}_0-1)\sin \frac{{\mathrm{\θ}}_0}{2}-3\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2}],$ $k_3=k_1^2+k_7^2$

$k_4=k_6^2+k_8^2,$ k ₅＝2(k ₁k ₆+k ₇k ₈)， $k_6=\frac{1}{2}[3\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2}+(3\cos {\mathrm{\θ}}_0-1)\sin \frac{{\mathrm{\θ}}_0}{2}]$

$k_7=\sin {\mathrm{\θ}}_0\cos \frac{{\mathrm{\θ}}_0}{2},$ $k_8=(3\cos {\mathrm{\θ}}_0-1)\cos \frac{{\mathrm{\θ}}_0}{2};$

H. the data in real time APU calculates avalanche source crag body breaking factor K by following formula _e:

$K_e=\frac{1}{2}[k_1{K}_1+k_2{K}_2+\sqrt{k_3{K}_1^2+k_4{K}_2^2+k_5{K}_1{K}_2}];$

I. the data in real time APU is calculated the stability factor of avalanche source crag body by following formula:

$F_s=\frac{K_{\mathrm{IC}}}{K_e};$

J. the data in real time APU is according to determining the residing safe condition of tested crag body by following judgement and sending corresponding early warning control signal and give warning device:

Work as F _s〉=1.20 o'clock, tested avalanche source crag body totally was in a safe condition;

As 1.05≤F _s＜1.20 o'clock, tested avalanche source crag body totally was in the basic security state;

As 0.98≤F _s＜1.05 o'clock, tested avalanche source crag body totally was in critical collapse state;

Work as F _s＜0.98 o'clock, tested avalanche source crag body totally was in collapse state.

8. method of carrying out the dangerous rock falling calamity early warning according to claim 7, it is characterized in that: in the c step, lay 5 taseometer test tensions, simultaneously, data in real time APU in the d step is gathered the mean value of stress data of 3 taseometers of stress numerical maximum in real time, as the numerical value of the real-time tensile stress sigma of avalanche source tension zone rock; In the c step, also lay 5 taseometer test shear stress in addition, simultaneously, the data in real time APU in the d step is got the wherein mean value of the stress data of 3 taseometers of stress numerical maximum, as the numerical value of the real-time shear stress τ of avalanche source tension zone rock.