CN117272457A - Comprehensive evaluation method for highway tunnel supporting system - Google Patents
Comprehensive evaluation method for highway tunnel supporting system Download PDFInfo
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- 238000005507 spraying Methods 0.000 claims abstract description 15
- 238000012360 testing method Methods 0.000 claims description 81
- 239000011435 rock Substances 0.000 claims description 33
- 239000007921 spray Substances 0.000 claims description 27
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Abstract
The invention belongs to the technical field of highway tunnel support system evaluation, and particularly discloses a highway tunnel support system comprehensive evaluation method, which comprises the following steps: acquiring the anchor rod axial force, the steel arch frame stress and the concrete spraying layer stress parameter data of an engineering site supporting structure; calculating to obtain an active supporting efficiency coefficient and a passive supporting efficiency coefficient; selecting a support structure with the highest active support efficiency coefficient and the highest passive support efficiency coefficient for coupling, and taking the support structure as an optimal coupling structure; calculating an active-passive support coupling support efficiency coefficient based on the optimal coupling structure yield load and the on-site active-passive support structure yield load; calculating an evaluation coefficient of an active-passive support system based on the active support efficiency coefficient, the passive support efficiency coefficient and the active-passive support coupling support efficiency coefficient; and evaluating the engineering site supporting effect based on the evaluation coefficient. The invention can realize the comprehensive evaluation of the active-passive coupling supporting structure and has good universality.
Description
Technical Field
The invention relates to the technical field of highway tunnel support system evaluation, in particular to a comprehensive evaluation method of a highway tunnel support system.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The tunnel support is a series of measures adopted in the tunnel construction process to ensure the stability and the safety of the tunnel, and mainly comprises support modes such as anchor bolt support, reinforced concrete lining, shotcrete support and the like.
The safety of tunnel construction is an important factor in determining project quality. With the continuous development of social economy, tunnel construction projects are increasing. However, in the construction process, the accident risk is extremely high due to the uncertainty factors such as the complex tunnel structure form, geological conditions, construction conditions and the like. Therefore, it is necessary to perform a tunnel support evaluation, evaluate the rationality and reliability of the tunnel support structure, and find out possible problems and risks.
As the tunnel engineering technology has matured, tunnels under various complex geological conditions are successively built and put into operation. Because of the huge differences of design schemes and construction processes under different geological conditions, the supporting arm sections need to be designed and constructed according to the actual conditions of engineering sites and are often in the condition of active-passive coupling supporting. The active-passive coupling support refers to a support mode of combining an active support system with a passive support system in the tunnel construction or operation process. The active supporting system generally refers to a supporting structure adopting active mechanical effects such as a prestressed anchor rod and the like, and can actively apply external forces such as load to surrounding rocks and the like to keep the stability of a tunnel. The passive supporting system refers to a supporting structure formed by the action of soil and the passive property of the supporting structure, such as a steel arch frame.
The active-passive coupling support needs to consider the mechanical property of the active-passive support system when acting independently and the mechanical property under the active-passive coupling support condition.
However, in the existing tunnel support evaluation method, only a single active support evaluation index is often considered, but the coupling action performance of the active support evaluation index and the passive support evaluation index in actual engineering cannot be comprehensively considered, so that the performance of the active-passive coupling support system is difficult to evaluate effectively, and reasonable support scheme optimization suggestions are provided.
Disclosure of Invention
In order to solve the problems, the invention provides a comprehensive evaluation method of a highway tunnel support system, which can comprehensively evaluate the performance of an active-passive support coupling structure.
In some embodiments, the following technical scheme is adopted:
a comprehensive evaluation method of a highway tunnel supporting system comprises the following steps:
acquiring the anchor rod axial force, the steel arch frame stress and the concrete spraying layer stress parameter data of an engineering site supporting structure;
respectively carrying out a standard anchor rod-surrounding rock coupling pre-tightening force loading test and a standard anchor rod-protective net-surrounding rock coupling pre-tightening force loading test to obtain a standard maximum compressive stress value and a compressive stress action range under the corresponding experiments; combining an anchor rod-surrounding rock coupling pre-tightening force loading test and an anchor rod-protective net-surrounding rock coupling pre-tightening force loading test under the site pre-tightening force condition, and calculating to obtain an active supporting efficiency coefficient;
respectively carrying out a standard steel arch loading test and a standard steel arch-concrete spray layer coupling loading test under the condition of the standard fixed concrete spray layer thickness to obtain a standard maximum flange stress safety coefficient under the corresponding test; combining an indoor steel arch loading test under the condition of the section of the field arch and a steel arch-concrete spray layer coupling loading test under the condition of the thickness of the field concrete spray layer, and calculating to obtain a passive supporting efficiency coefficient;
selecting a support structure with the highest active support efficiency coefficient and the highest passive support efficiency coefficient for coupling, and taking the support structure as an optimal coupling structure; calculating an active-passive support coupling support efficiency coefficient based on the optimal coupling structure yield load and the on-site active-passive support structure yield load;
calculating an evaluation coefficient of an active-passive support system based on the active support efficiency coefficient, the passive support efficiency coefficient and the active-passive support coupling support efficiency coefficient; and evaluating the engineering site supporting effect based on the evaluation coefficient.
Further comprises: based on the anchor rod axial force, the steel arch frame stress and the concrete spraying layer stress parameter data of the engineering site supporting structure, single active supporting and single passive supporting structure stability evaluation is carried out;
if each parameter data should satisfy the following conditions:
(1) the anchor rod axial force value of the engineering site supporting structure is not more than the anchor rod yield strength;
(2) the stress value of the steel arch of the engineering site supporting structure is not more than the yield strength of the steel arch;
(3) the stress value of the concrete spraying layer of the engineering site supporting structure is not more than the yield strength of the concrete spraying layer;
the stability of the single active support and the single passive support on site is proved, and the coupling stability of the active support and the passive support is evaluated; otherwise, the engineering site supporting structure is unstable.
After evaluating the engineering site supporting effect, the method further comprises the following steps:
and (3) carrying out optimization feedback on the field support system based on the evaluation result, and setting the evaluation coefficient in a safety zone and keeping the highest load safety space under the condition of meeting the economic requirement by adjusting and optimizing the design scheme of the active-passive support structure.
Compared with the prior art, the invention has the beneficial effects that:
(1) According to the invention, monitoring sections are distributed equidistantly in the engineering construction stage, and continuous monitoring is carried out on the axial force of the anchor rod, the deformation and the stress of the arch frame and the deformation and the stress of the concrete lining, so that the performance parameters of the actual supporting structure of the engineering site are obtained, and the stability evaluation of the single active supporting structure and the single passive supporting structure of the site can be carried out; if the evaluation is stable, further performing active-passive coupling stability evaluation; if any support structure is evaluated to be unstable, the instability of the support system is directly judged.
(2) According to the invention, the mechanical property test of the active supporting structure, the mechanical property test of the passive supporting structure and the comparison test of the coupling supporting system are respectively carried out, and the active supporting efficiency coefficient, the passive supporting efficiency coefficient and the active-passive supporting coupling supporting efficiency coefficient are respectively obtained through the tests by combining with the field engineering conditions; based on the coefficients, the evaluation coefficients are calculated, so that the comprehensive evaluation of the active-passive coupling support structure is realized, and the method has good universality.
(3) According to the invention, the evaluation coefficient is compared with the safety interval, the on-site support system is optimally fed back based on the comparison result, and the design scheme of the active-passive support structure is adjusted and optimized, so that the evaluation coefficient is placed in the safety interval and the highest load safety space is maintained under the condition of meeting the economic requirement.
Additional features and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
FIG. 1 is a schematic diagram of a stability evaluation process of a support system under a single condition in an embodiment of the present invention;
fig. 2 is a schematic diagram of a comprehensive evaluation process of the active-passive coupled support structure in the embodiment of the invention.
Detailed Description
It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
Example 1
In one or more embodiments, a comprehensive evaluation method of a highway tunnel supporting system is disclosed, and in combination with fig. 1 and fig. 2, the method specifically includes the following steps:
step (1): and monitoring parameters of the engineering site supporting structure, and obtaining the anchor rod axial force, the steel arch frame stress and the concrete spraying layer stress parameter data of the engineering site supporting structure.
In this embodiment, with reference to fig. 1, monitoring sections are equidistantly arranged in the engineering construction stage, and continuous monitoring is performed on the axial force of the anchor rod, the deformation and stress of the arch frame, and the deformation and stress of the concrete lining, so as to obtain the performance parameters of the actual supporting structure in the engineering site, and the stability evaluation of the single active supporting structure and the single passive supporting structure is performed.
For equidistant arrangement of monitoring sections, 3 groups of monitoring sections are required to be arranged, one group is respectively arranged at the position 20m away from the tunnel inlet and outlet, and one group is arranged at the center of the tunnel; for the monitoring of the axial force of the anchor rod, a strain gauge is arranged in the center of the monitoring anchor rod before the anchor rod is applied; for arch frame deformation and stress monitoring, considering that the thickness of an arch frame structure causes different internal and external deformation, monitoring points are arranged at the outer side, the center and the inner side of the arch frame, and the measuring points are positioned at the left and right waists and the vault of the arch frame; for deformation and stress monitoring of the concrete spraying layer, monitoring points are arranged at the inner side of the concrete spraying layer, and the measuring points are positioned at the left and right arches and the arch crown.
For the stability evaluation of a single active support and a single passive support structure, the axial force of an anchor rod, the stress of an arch frame and the stress of concrete are respectively and independently evaluated, and the monitoring parameters are as follows:
wherein F is c To monitor the axial force of the anchor rod in situ, F cs For the yield strength of the anchor rod, F a To monitor the stress value of the steel arch on site, F as Is the yield strength of the steel arch, F o F for monitoring the stress value of the concrete spraying layer on site os The yield strength of the concrete sprayed layer is obtained.
If the coupling stability is met, the single active support and the single passive support are stable in structure, and the coupling stability of the active support and the passive support is evaluated; otherwise, the engineering site support structure is unstable, and subsequent evaluation is not needed.
Step (2): and (5) carrying out the mechanical property test of the active supporting structure.
In the embodiment, a standard anchor rod-surrounding rock coupling pre-tightening force loading test and a standard anchor rod-protective net-surrounding rock coupling pre-tightening force loading test are respectively carried out to obtain a standard maximum compressive stress value and a compressive stress action range under the corresponding experiments; combining an anchor rod-surrounding rock coupling pre-tightening force loading test and anchor rod-protective net-surrounding rock coupling pre-tightening force adding under the condition of on-site pre-tightening forceLoad test, calculating to obtain active support efficiency coefficient delta a 。
The specific process is as follows:
(2-1) for a standard indoor anchor rod (rope) -surrounding rock coupling pretightening force loading test, intercepting an anchor rod (rope) to be tested with 3000mm, penetrating the anchor rod (rope) into a precast concrete surrounding rock simulation material, setting strain gauges at equal intervals along the trend of the anchor rod (rope), fixing one end of the anchor rod (rope) to a hydraulic loading device by using a lockset, fixing the other end of the anchor rod (rope) to the surrounding rock simulation material by using a tray and the lockset, stretching one end of a hydraulic loading oil cylinder, applying prestress according to a gradient, wherein the application interval is 30% -50% of the yield load of the anchor rod (rope), and applying the gradient is 5% of the yield load.
Recording and deducing the maximum compressive stress and the action range of the compressive stress of each group of tests, and calculating the prestress effect parameter gamma a ：
Wherein sigma i For the maximum compressive stress value in the ith set of experiments, σ max For the maximum compressive stress value, s, in all sets of experiments i Sum s i+1 The range of compressive stress in the i and i+1 groups of tests, respectively.
(2-2) for a standard anchor rod (rope) -protective net-surrounding rock coupling pretightening force loading test, intercepting an anchor rod (rope) to be tested with 3000mm, penetrating a precast concrete surrounding rock simulation material, laying a protective net with the same model as that of the site, arranging strain gages at equal distance along the trend of the anchor rod (rope) by the material, fixing one end of the anchor rod (rope) to a hydraulic loading device by using a lockset, fixing the other end of the anchor rod (rope) to the protective net by using a tray and the lockset, applying prestress to one stretching end of a hydraulic loading oil cylinder according to a gradient, wherein the application interval is 30% -50% of yield load of the anchor rod (rope), and the application gradient is 5% of the yield load.
Recording and deducing the maximum compressive stress and the action range of the compressive stress of each group of tests, and calculating the prestress effect parameter gamma a ′：
Wherein sigma i For the maximum compressive stress value in the ith set of experiments, σ max For the maximum compressive stress value, s, in all sets of experiments i Sum s i+1 Is the range of compressive stress in the i and i+1 groups of tests.
Will gamma a And gamma a Taking the prestress value with the maximum value as an optimal standard group; selecting gamma a The corresponding prestress at maximum is taken as a first optimal standard group, gamma a The corresponding prestress at 'maximum' is used as a second optimal standard group; and calculating a first maximum compressive stress value and a first compressive stress action range of the first optimal standard group, and a second maximum compressive stress value and a second compressive stress action range of the second optimal standard group.
And (2-3) for an anchor rod (rope) -surrounding rock coupling pre-tightening force loading test under the condition of combining site pre-tightening force, intercepting an anchor rod (rope) to be tested with 3000mm, penetrating the anchor rod (rope) into a precast concrete surrounding rock simulation material, setting strain gauges at equal intervals along the trend of the anchor rod (rope), fixing one end of the anchor rod (rope) to a hydraulic loading device by using a lockset, fixing the other end of the anchor rod (rope) to the surrounding rock simulation material by using a tray and the lockset, applying pre-stress to one stretched end of a hydraulic loading oil cylinder according to engineering site standards, and recording and deducing the action range of a third maximum compressive stress and a third compressive stress.
And (2-4) for an anchor rod (rope) -protective net-surrounding rock coupling pre-tightening force loading test under the condition of combining site pre-tightening force, intercepting an anchor rod (rope) to be tested, penetrating a precast concrete surrounding rock simulation material, laying a protective net with the same model as the site, arranging strain gauges at equal intervals along the trend of the anchor rod (rope), fixing one end of the anchor rod (rope) to a hydraulic loading device by using a lockset, fixing the other end of the anchor rod (rope) to the protective net by using a tray and the lockset, applying pre-stress on one stretching end of a hydraulic loading oil cylinder according to engineering site standard, and recording and deducing a fourth maximum compressive stress and a fourth compressive stress action range.
(2-5) based on the obtained first maximum compressive stress value, first compressive stress application range, second maximum compressive stress value, second compressive stress application range, third maximum compressive stress value, third compressive stress application range, fourth maximum compressive stressCalculating the active support efficiency coefficient delta according to the large compressive stress value and the fourth compressive stress acting range a The method specifically comprises the following steps:
wherein sigma smax For a first maximum compressive stress value, σ sc Is the third maximum compressive stress value, s sp Is the first compressive stress action range s sc Is the third compressive stress action range; sigma (sigma) s ′ max For the second maximum compressive stress value, σ s ′ c For the fourth maximum compressive stress value, σ s ′ p For the second compressive stress range, sigma s ′ c Is the fourth compressive stress application range.
Step (3): and (5) carrying out the mechanical property test of the passive supporting structure.
In the embodiment, a standard steel arch loading test and a standard steel arch-concrete spray layer coupling loading test under the standard fixed concrete spray layer thickness are respectively carried out to obtain a standard maximum flange stress safety coefficient under the corresponding test; combining an indoor steel arch loading test under the condition of the section of the field arch and a steel arch-concrete spray layer coupling loading test under the condition of the thickness of the field concrete spray layer, and calculating to obtain a passive supporting efficiency coefficient delta p 。
The specific process is as follows:
(3-1) for a standard indoor steel arch loading test, determining a similar scale according to the actual section size of an engineering site, and if the section size is smaller, carrying out a full scale arch loading test; the test section selects the section of the existing main stream I-steel, channel steel and U-steel arch centering with the same section area as the field arch centering, and the single hydraulic loading head loads F h The method comprises the following steps:
wherein S is st The total area sigma of the contact surface of the steel arch frame and the surrounding rock h For the ground of engineering siteThe force magnitude, n, is the number of loading heads of the hydraulic loading device.
And (3) carrying out a loading test until the steel arch exceeds the flange stress safety coefficient, wherein strain gauges are arranged on the upper flange and the lower flange of the steel arch, the monitoring positions are the arch center, the arch waists on two sides and the arch bottom center, and the flange stress safety coefficient is as follows:
wherein f ult Is the ultimate strength of steel material, sigma i For actually measuring the flange stress of the steel frame, when lambda>2, considering the steel arch to be in a safe state; when 1.5<λ<2, in a fail safe state; when lambda is<1.5, is in a dangerous state.
And calculating a flange stress safety coefficient lambda, taking the maximum test object with the lambda value as a standard group, and taking the flange stress safety coefficient of the standard group as a first maximum flange stress safety coefficient.
(3-2) for a steel arch frame-concrete spray layer coupling loading test under the condition of fixed concrete spray layer thickness, determining a similar scale according to the actual section size of an engineering site, if the section size is smaller, carrying out a full scale arch frame loading test, and correcting the concrete spray layer thickness according to the similar scale; the test section selects the section of the existing main stream I-steel, channel steel and U-steel arch centering with the same section area as the field arch centering, and the single hydraulic loading head loads F h The method comprises the following steps:
wherein S is ct The total area of the contact surface of the concrete lining and the surrounding rock is shown as sigma, the ground stress at the engineering site is shown as sigma, and n is the number of loading heads of the hydraulic loading device.
And (3) carrying out a loading test until the steel arch exceeds the flange stress safety coefficient, wherein strain gauges are arranged on the upper flange and the lower flange of the steel arch, the monitoring positions are the arch center, the arch waists on two sides and the arch bottom center, and the flange stress safety coefficient is as follows:
wherein f ult Is the ultimate strength of steel material, sigma i For actually measuring the flange stress of the steel frame, when lambda>2, considering the steel arch to be in a safe state; when 1.5<λ<2, in a fail safe state; when lambda is<1.5, is in a dangerous state.
And calculating a flange stress safety coefficient lambda, arranging strain gauges at the centers of the arch crown center, the arch waists at two sides and the arch bottom center of the concrete lining, taking a test object with the maximum lambda value as a standard group, and taking the flange stress safety coefficient of the standard group as a second maximum flange stress safety coefficient.
(3-3) for the indoor steel arch loading test under the condition of the section of the field arch, selecting a similar scale which is completely the same as that of the standard indoor steel arch loading test, selecting the section form of the test section which is the same as that of the field arch, and loading a single hydraulic loading head with a load F h The method comprises the following steps:
wherein S is st The total area of the contact surface of the steel arch frame and the surrounding rock is shown as sigma, the ground stress at the engineering site is shown as sigma, and n is the number of loading heads of the hydraulic loading device.
And (3) carrying out a loading test until the steel arch exceeds the flange stress safety coefficient, wherein strain gauges are arranged on the upper flange and the lower flange of the steel arch, the monitoring positions are the arch center, the arch waists on two sides and the arch bottom center, and the first flange stress safety coefficient is as follows:
wherein f ult Is the ultimate strength of steel material, sigma i For actually measuring the flange stress of the steel frame, when lambda>2, considering the steel arch to be in a safe state; when 1.5<λ<2, in a fail safe state; when lambda is<1.5, is in a dangerous state.
(3-4) for the steel arch frame-concrete spray layer coupling loading test under the on-site concrete spray layer thickness, selecting a similar scale which is completely the same as that of the standard indoor steel arch frame loading test, selecting a section form which is the same as that of the on-site arch frame, and loading F by a single hydraulic loading head h The method comprises the following steps:
wherein S is ct The total area of the contact surface of the concrete lining and the surrounding rock is shown as sigma, the ground stress at the engineering site is shown as sigma, and n is the number of loading heads of the hydraulic loading device.
And (3) carrying out a loading test until the steel arch exceeds the flange stress safety coefficient, wherein strain gauges are arranged on the upper flange and the lower flange of the steel arch, the monitoring positions are the arch center, the arch waists on two sides and the arch bottom center, and the second flange stress safety coefficient is as follows:
wherein f ult Is the ultimate strength of steel material, sigma i For actually measuring the flange stress of the steel frame, when lambda>2, considering the steel arch to be in a safe state; when 1.5<λ<2, in a fail safe state; when lambda is<1.5, is in a dangerous state.
(3-5) calculating a passive support efficiency factor delta based on the first maximum flange stress safety factor, the first flange stress safety factor, the second maximum flange stress safety factor, and the second flange stress safety factor p The method specifically comprises the following steps:
wherein lambda is max Is the first maximum flange stress safety coefficient lambda in the standard indoor steel arch loading test sc First flange stress safety coefficient lambda 'for loading test of indoor steel arch' max For fixing the thickness of the concrete spray layerSecond maximum flange stress safety coefficient, lambda 'in steel arch-concrete spray coupling loading test' sc And the second flange stress safety coefficient of the steel arch frame-concrete spray layer coupling loading test under the on-site concrete spray layer thickness is obtained.
Step (4): and (5) comparing and testing the coupling support system.
In the embodiment, according to the size of an indoor test device, selecting the tested optimal supporting structure for coupling, taking the optimal supporting structure as an optimal coupling structure, carrying out a coupling loading model test of a full scale or a certain similar scale, and monitoring the axial force, arch frame deformation and stress of an anchor rod of the optimal active-passive supporting structure and the deformation and stress of a concrete lining;
based on experimental result data of the optimal coupling structure and experimental result data of the on-site active-passive support structure, calculating an active-passive support coupling support efficiency coefficient delta u ；
The specific process is as follows:
selecting the active supporting efficiency coefficient delta in the step (2) and the step (3) a And a passive support efficiency coefficient delta p The highest active-passive support structure is taken as an optimal structure combination to be a test object, and experimental result data of the optimal active-passive support structure is determined; selecting a site structure combination as a test object, carrying out an active-passive coupling loading model test of a full scale or a certain similar scale according to the size of an indoor test device, and determining experimental result data of a site active-passive supporting structure; calculating the efficiency coefficient delta of the active-passive support coupling support u ：
Wherein n is the number of monitoring sections, F c To monitor the axial force of the anchor rod in situ, F cb Is the theoretical optimal structural anchor rod axial force value, S a For on-site monitoring of deformation of steel arch, S ab Is the theoretical optimal structural steel arch frame deformation quantity delta o S for monitoring deformation of concrete spraying layer on site ob The deformation of the concrete spray layer is the theoretical optimal structure.
Step (5): based on active support efficiency coefficient delta a Efficiency coefficient delta of passive support p And an active-passive support coupling support efficiency coefficient delta u Calculating an evaluation coefficient of the active-passive support system; and evaluating the engineering site supporting effect based on the evaluation coefficient.
Specifically, for the evaluation coefficient ζ of the underground engineering tunnel active-passive support system, specifically:
wherein L is n Load borne by the passive supporting structure, L p Load borne by active supporting structure, L s Is the surrounding rock load.
The embodiment evaluates the engineering site supporting effect based on the evaluation coefficient, and specifically comprises the following steps:
comparing the evaluation coefficient result with the safety interval:
(1) if the evaluation coefficient is smaller than the minimum value of the safety interval, the supporting system is considered to be unsafe, and the supporting system needs to be redesigned;
(2) if the evaluation coefficient is smaller than the set percentage p of the maximum value of the safety interval, the supporting system is considered to be unsafe, and the active or passive supporting system is required to be optimized independently;
(3) if the evaluation coefficient is larger than the set percentage p of the maximum value of the safety interval, the support system is considered to be safe without modification.
Wherein p is a set value, such as: this example was chosen to be 70%.
In the coefficient safety interval in this embodiment, the minimum value is the evaluation coefficient corresponding to the weakest active-passive support system which meets the support load distribution composition, and the maximum value is the evaluation coefficient corresponding to the optimal active-passive support system.
Step (6): and according to the comparison result of the evaluation coefficient result and the safety interval, carrying out optimization feedback on the field support system, and adjusting and optimizing the design scheme of the active-passive support structure, so that the evaluation coefficient is placed in the safety interval and a higher load safety space is ensured under the condition of meeting the economic requirement.
The comprehensive evaluation method of the highway tunnel supporting system can comprehensively consider the coupling effect of the active-passive supporting in the actual engineering, and has more accurate evaluation result and stronger practicability; meanwhile, the active-passive support coupling structure can be subjected to feedback optimization according to the evaluation result, so that the support system has a higher load safety space.
While the foregoing description of the embodiments of the present invention has been presented in conjunction with the drawings, it should be understood that it is not intended to limit the scope of the invention, but rather, it is intended to cover all modifications or variations within the scope of the invention as defined by the claims of the present invention.
Claims (10)
1. The comprehensive evaluation method of the highway tunnel supporting system is characterized by comprising the following steps of:
acquiring the anchor rod axial force, the steel arch frame stress and the concrete spraying layer stress parameter data of an engineering site supporting structure;
respectively carrying out a standard anchor rod-surrounding rock coupling pre-tightening force loading test and a standard anchor rod-protective net-surrounding rock coupling pre-tightening force loading test to obtain a standard maximum compressive stress value and a compressive stress action range under the corresponding experiments; combining an anchor rod-surrounding rock coupling pre-tightening force loading test and an anchor rod-protective net-surrounding rock coupling pre-tightening force loading test under the site pre-tightening force condition, and calculating to obtain an active supporting efficiency coefficient;
respectively carrying out a standard steel arch loading test and a standard steel arch-concrete spray layer coupling loading test under the condition of the standard fixed concrete spray layer thickness to obtain a standard maximum flange stress safety coefficient under the corresponding test; combining an indoor steel arch loading test under the condition of the section of the field arch and a steel arch-concrete spray layer coupling loading test under the condition of the thickness of the field concrete spray layer, and calculating to obtain a passive supporting efficiency coefficient;
selecting a support structure with the highest active support efficiency coefficient and the highest passive support efficiency coefficient for coupling, and taking the support structure as an optimal coupling structure; calculating an active-passive support coupling support efficiency coefficient based on the optimal coupling structure yield load and the on-site active-passive support structure yield load;
calculating an evaluation coefficient of an active-passive support system based on the active support efficiency coefficient, the passive support efficiency coefficient and the active-passive support coupling support efficiency coefficient; and evaluating the engineering site supporting effect based on the evaluation coefficient.
2. The method for comprehensively evaluating a highway tunnel supporting system according to claim 1, further comprising: based on the anchor rod axial force, the steel arch frame stress and the concrete spraying layer stress parameter data of the engineering site supporting structure, single active supporting and single passive supporting structure stability evaluation is carried out;
if each parameter data should satisfy the following conditions:
(1) the anchor rod axial force value of the engineering site supporting structure is not more than the anchor rod yield strength;
(2) the stress value of the steel arch of the engineering site supporting structure is not more than the yield strength of the steel arch;
(3) the stress value of the concrete spraying layer of the engineering site supporting structure is not more than the yield strength of the concrete spraying layer;
the stability of the single active support and the single passive support on site is proved, and the coupling stability of the active support and the passive support is evaluated; otherwise, the engineering site supporting structure is unstable.
3. The method for comprehensively evaluating a highway tunnel supporting system according to claim 1, further comprising, after evaluating the supporting effect on the engineering site:
and (3) carrying out optimization feedback on the field support system based on the evaluation result, and setting the evaluation coefficient in a safety zone and keeping the highest load safety space under the condition of meeting the economic requirement by adjusting and optimizing the design scheme of the active-passive support structure.
4. The comprehensive evaluation method of a highway tunnel supporting system according to claim 1, wherein the active supporting efficiency coefficient is calculated, specifically:
calculating a prestress effect parameter gamma through a standard anchor rod-surrounding rock coupling prestress loading test a The method comprises the steps of carrying out a first treatment on the surface of the The prestress effect parameter gamma is calculated through a standard anchor rod-protective net-surrounding rock coupling prestress loading test a ′；
Selecting gamma a The corresponding prestress at maximum is taken as a first optimal standard group, gamma a The corresponding prestress at 'maximum' is used as a second optimal standard group; calculating a first maximum compressive stress value and a first compressive stress action range of the first optimal standard group, and a second maximum compressive stress value and a second compressive stress action range of the second optimal standard group;
determining a third maximum compressive stress value and a third compressive stress acting range through an anchor rod-surrounding rock coupling pre-tightening force loading test under the field pre-tightening force condition; determining a fourth maximum compressive stress value and a fourth compressive stress acting range through an anchor rod-protective net-surrounding rock coupling pre-tightening force loading test under the condition of on-site pre-tightening force;
and calculating the active support efficiency coefficient based on the calculated maximum compressive stress values and the compressive stress acting ranges.
5. The comprehensive evaluation method of a highway tunnel supporting system according to claim 1, wherein the passive supporting efficiency coefficient is calculated, specifically:
selecting an experimental object with the largest flange stress safety coefficient as a standard group through a standard indoor steel arch loading test, and calculating a first largest flange stress safety coefficient; the method comprises the steps of calculating a first flange stress safety coefficient through an indoor steel arch loading test under the condition of an on-site arch section;
selecting an experimental object with the largest flange stress safety coefficient as a standard group through a steel arch frame-concrete spray layer coupling loading test under the standard fixed concrete spray layer thickness, and calculating a second largest flange stress safety coefficient; calculating to obtain a second flange stress safety coefficient through a steel arch frame-concrete spray layer coupling loading test under the on-site concrete spray layer thickness;
and calculating the passive support efficiency coefficient based on the first maximum flange stress safety coefficient, the first flange stress safety coefficient, the second maximum flange stress safety coefficient and the second flange stress safety coefficient.
6. The comprehensive evaluation method of a highway tunnel supporting system according to claim 1, wherein the calculation of the efficiency coefficient of the active-passive supporting coupling supporting system is specifically as follows:
taking the optimal coupling structure as an experimental object, and carrying out a loading model test to obtain experimental result data of the optimal coupling structure;
selecting an on-site active-passive supporting structure as a test object, and carrying out an active-passive coupling loading model test of a full scale or a certain similar scale according to the size of an indoor test device to obtain experimental result data of the on-site active-passive supporting structure;
and calculating the coupling support efficiency coefficient of the active-passive support based on experimental result data of the optimal coupling structure and the active-passive support structure on site.
7. The comprehensive evaluation method of a highway tunnel supporting system according to claim 6, wherein the active-passive supporting coupling supporting efficiency coefficient is specifically:
wherein n is the number of monitoring sections, F c To monitor the axial force of the anchor rod in situ, F cb Is the theoretical optimal structural anchor rod axial force value, S a For on-site monitoring of deformation of steel arch, S ab Is the theoretical optimal structural steel arch frame deformation quantity S o S for monitoring deformation of concrete spraying layer on site ob The deformation of the concrete spray layer is the theoretical optimal structure.
8. The comprehensive evaluation method of a highway tunnel supporting system according to claim 1, wherein the evaluation coefficients of the active-passive supporting system are calculated, specifically:
wherein L is n Load borne by the passive supporting structure, L p Load borne by active supporting structure, L s Is the surrounding rock load; delta a For actively supporting efficiency coefficient, delta p For passive supporting efficiency coefficient S u The efficiency coefficient is supported by the coupling of active and passive supports.
9. The comprehensive evaluation method of a highway tunnel supporting system according to claim 1, wherein the evaluation of the engineering site supporting effect based on the evaluation coefficient is specifically as follows:
comparing the evaluation coefficient with a safety interval:
if the evaluation coefficient is smaller than the minimum value of the safety interval, the supporting system is considered to be unsafe, and the supporting system needs to be redesigned;
if the evaluation coefficient is smaller than the set percentage p of the maximum value of the safety interval, the supporting system is considered to be unsafe, and the active or passive supporting system is required to be optimized independently;
if the evaluation coefficient is greater than the set percentage p of the maximum value of the safety interval, the support system is considered to be safe; p is a set value.
10. The method for comprehensively evaluating a highway tunnel supporting system according to claim 9, wherein the minimum value of the safety interval is an evaluation coefficient corresponding to the weakest active-passive supporting system meeting the supporting load distribution composition, and the maximum value is an evaluation coefficient corresponding to the optimal active-passive supporting system meeting the supporting load distribution composition.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102226408A (en) * | 2011-06-21 | 2011-10-26 | 北京交通大学 | Loess tunnel anchor bar support device |
| CN103541739A (en) * | 2013-09-13 | 2014-01-29 | 北京交通大学 | Shallow-buried long-span small-clear-distance loess tunnel supporting system |
| CN110346213A (en) * | 2019-08-07 | 2019-10-18 | 安徽建筑大学 | A kind of goaf tunnel Xia Chuan Assessment of Surrounding Rock Stability method |
| WO2021007960A1 (en) * | 2019-07-15 | 2021-01-21 | 中国矿业大学 | Rational width determination method for gob-side entry driving narrow coal pillar based on crack evolution |
| CN113107525A (en) * | 2021-04-13 | 2021-07-13 | 中铁隧道集团二处有限公司 | Support system for extruded large-deformation tunnel, construction method and application |
| CN115326601A (en) * | 2022-10-14 | 2022-11-11 | 中国矿业大学(北京) | Dynamic impact test and evaluation method for anchor net coupled supporting rock mass |
| CN115680721A (en) * | 2022-11-18 | 2023-02-03 | 西南交通大学 | Tunnel deformation active control supporting structure system and parameter solving method |
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102226408A (en) * | 2011-06-21 | 2011-10-26 | 北京交通大学 | Loess tunnel anchor bar support device |
| CN103541739A (en) * | 2013-09-13 | 2014-01-29 | 北京交通大学 | Shallow-buried long-span small-clear-distance loess tunnel supporting system |
| WO2021007960A1 (en) * | 2019-07-15 | 2021-01-21 | 中国矿业大学 | Rational width determination method for gob-side entry driving narrow coal pillar based on crack evolution |
| CN110346213A (en) * | 2019-08-07 | 2019-10-18 | 安徽建筑大学 | A kind of goaf tunnel Xia Chuan Assessment of Surrounding Rock Stability method |
| CN113107525A (en) * | 2021-04-13 | 2021-07-13 | 中铁隧道集团二处有限公司 | Support system for extruded large-deformation tunnel, construction method and application |
| CN115326601A (en) * | 2022-10-14 | 2022-11-11 | 中国矿业大学(北京) | Dynamic impact test and evaluation method for anchor net coupled supporting rock mass |
| CN115680721A (en) * | 2022-11-18 | 2023-02-03 | 西南交通大学 | Tunnel deformation active control supporting structure system and parameter solving method |
Non-Patent Citations (2)
| Title |
|---|
| 王琦 等: ""Mechanical behaviour analysis and support system field experiment of confined concrete arches"", 《SPRINGER》, 26 April 2019 (2019-04-26), pages 970 - 983 * |
| 鹿伟 等: ""深部软岩巷道方钢约束混凝土拱架基本构件 力学特性及参数影响机制研究"", 《采矿与安全工程学报》, vol. 37, no. 3, 31 May 2020 (2020-05-31), pages 473 - 480 * |
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