CN104532835A - Method for measuring composite anti-drawing reinforcing design strength of anchor rod bundle - Google Patents

Method for measuring composite anti-drawing reinforcing design strength of anchor rod bundle Download PDF

Info

Publication number
CN104532835A
CN104532835A CN201410787650.5A CN201410787650A CN104532835A CN 104532835 A CN104532835 A CN 104532835A CN 201410787650 A CN201410787650 A CN 201410787650A CN 104532835 A CN104532835 A CN 104532835A
Authority
CN
China
Prior art keywords
anchor
bundle
anchor pole
plucking
bar bundle
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201410787650.5A
Other languages
Chinese (zh)
Other versions
CN104532835B (en
Inventor
贺可强
郭璐
郭栋
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Qingdao University of Technology
Original Assignee
Qingdao University of Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qingdao University of Technology filed Critical Qingdao University of Technology
Priority to CN201410787650.5A priority Critical patent/CN104532835B/en
Publication of CN104532835A publication Critical patent/CN104532835A/en
Application granted granted Critical
Publication of CN104532835B publication Critical patent/CN104532835B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D33/00—Testing foundations or foundation structures
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
    • E02D5/74—Means for anchoring structural elements or bulkheads
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D2600/00—Miscellaneous
    • E02D2600/30—Miscellaneous comprising anchoring details

Landscapes

  • Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Piles And Underground Anchors (AREA)

Abstract

The invention discloses a method for measuring composite anti-drawing reinforcing design strength of an anchor rod bundle. The method comprises the steps that an anchor rod parameter selection and anti-drawing experimental scheme is determined; strength parameters of anchor rods, anchoring segment grouting and strata are determined; the ultimate anti-drawing strength of the anchor bundle damaged along a mortar interface is determined; the ultimate anti-drawing strength of the anchor bundle damaged along a peripheral stratum interface is determined; the composite anti-drawing reinforcing design strength of the anchor rod bundle is determined. Based on the action mechanism of the anchor rod bundle and the anchor rods, the anti-drawing reinforcing strength relation and interaction relation between the anchor rod bundle and the anchor rods are explored, and the method for measuring the anti-drawing reinforcing strength of the anchor rod bundle is studied and determined. The anti-drawing reinforcing strength design perimeters of the anchor rod bundle are directly determined according to parameters obtained by an anti-drawing experiment of the anchor rods, an effective anti-drawing reinforcing strength design method is provided for design of composite anchor rod bundle reinforcing engineering, and important practical value in reinforcing engineering design construction of the anchor rod bundle is achieved.

Description

The assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity
Technical field
The present invention relates to anchor bar bundle reinforcing design field, be specifically related to a kind of anchor bar bundle compound resistance to plucking fastening strength rapid assay methods.
Background technology
Bolt support is a kind of safe, economic support pattern, and it is the general name of the supporting and protection structure based on anchor pole, and it comprises the support forms such as anchor pole, shotcrete, anchor and spray net.Its technology is exactly oblique pore-forming in soil layer, grouting body is poured into after imbedding anchor pole, the anchoring section of tension anchor pole is fixed in rock (soil) layer of side slope or ground, the other end is connected with engineering works, in order to supporting due to soil pressure, water pressure put on the thrust of building, rely on the frictional force between anchoring body and stratum, the load acted in supporting and protection structure is born in the bond stress of pull bar and anchoring body and the intensity acting in conjunction of pull bar, to maintain the stable of building and rock mass.Compared with traditional support pattern, anchor rod anchored technology have himself distinguishing feature, its feature to have structure is simple, easy construction, supporting effect is good, labour intensity is low, efficiency is high and economic benefit is obvious etc.Bolt support technology, except hold good state of development in underground construction, slope project, structural anti-buoyancy engineering, the continuation of insurance of deep-foundation pit engineering relaying, there has also been considerable progress in gravity dam stabilization works, bridge engineering and overturning or slip resistance analysis, antiseismic engineering.The development of the mooring rod technique of China, in the test of the underground engineering field such as coal, metallurgy from the initial stage fifties, develops the fields such as traffic, water power, civil construction subsequently rapidly, have accumulated rich experience.From 1993 to 1999, according to the preliminary statistics, only slope project and deep-foundation pit engineering, the annual consumption of anchor pole is about 3000km-3500km.Ground anchorage, as strengthening stratum or the main method utilizing formation strength transferring structure thing pulling force, obtains a wide range of applications in building, water conservancy and construction work.
At present, anchor pole resistance to plucking fastening strength defining method is mainly divided into experimental method and theory method.Experimental method, namely by anchor pole anti-pulling test, is determined anchor rod ultimate resistance to plucking fastening strength and obtains relevant design parameter.Anchor rod ultimate resistance to plucking fastening strength is determined by Q-s curve, and it is subject to add load mode, stop the impact of the factor such as experiment condition, observation interval.Theory method builds on anchor pole to be on the basis of elastic-plastic behavior, think that resistance to plucking fastening strength depends primarily on the adhesion stress between the grouting body of anchoring section and Rock And Soil and the adhesion stress between reinforcing bar and grouting body, its limit resistance to plucking fastening strength is directly proportional to anchorage length, and anchor rod ultimate resistance to plucking fastening strength is P=π DLf according to different mode of failure calculating formulas ror P=π dLf s.In formula, D is the anchoring body diameter of anchor pole; D is bar diameter; L is the anchoring depth of anchor pole; f rfor the adhesion strength limiting value between anchor rod anchored grouting body and Rock And Soil; f sfor the adhesion strength limiting value between reinforcing bar and grouting body.
Anchor bar bundle is the supporting and protection structure be derived by anchor pole, and it is that the anchor pole of more than three and three bands together, and jointly plays a role, is mainly used in following three kinds of situations: the geological conditions of side slope or because of requirement of engineering do not allow to beat multiple hole time; Large-scale side slope sliding force is large, and single anchor rod can not meet requirement of engineering, and arranges many anchor poles and can produce when influencing each other; During in order to raise the efficiency and reduce costs, make a call to a hole and just can solve, therefore without the need to multiple hole of sounding the night watches.At present, anchor bar bundle is widely used in the middle of engineering practice, but lags far behind engineering practice about its measuring technology and technique study.Because many stabilization works test conditionss are limit or pullout tests equipment limitation, special in large-scale anchor bar bundle and high resistance to plucking fastening strength stabilization works, directly cannot use the pullout tests intensity parameter of anchor bar bundle pullout tests equipment determination anchor bar bundle, therefore can not the compound resistance to plucking fastening strength design parameters of Accurate Determining anchor bar bundle, and often by virtue of experience construct in Practical Project, bring great risk of instability for anchor bar bundle Reinforcement engineering or cause the waste of human and material resources and financial resources.For this reason, how to utilize the compound resistance to plucking fastening strength relevant design parameter of single anchor rod pullout tests data determination anchor bar bundle, become the important problems of engineering design that current anchor bar bundle Reinforcement engineering one is urgently to be resolved hurrily.
Summary of the invention
The object of the invention is for overcoming above-mentioned the deficiencies in the prior art, according to the mechanism of action of anchor bar bundle and anchor pole, explore contacting and interaction relationship of anchor bar bundle and anchor pole resistance to plucking fastening strength, a kind of assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity is provided, according to the parameter that the anti-pulling test of anchor pole obtains, directly determine the resistance to plucking fastening strength design parameters of anchor bar bundle, the design for Composite Bolt bundle stabilization works provides a kind of effectively resistance to plucking fastening strength method for designing.
For achieving the above object, the present invention adopts following technical proposals:
An assay method for anchor bar bundle compound resistance to plucking reinforcing design intensity, comprising:
The first step: choosing and the determination of anti-pulling test scheme of bolt design parameters
According to geological conditions and engineering practice, design and determine to form the bolt diameter d of anchor bar bundle and anchor rod anchored segment length L, and according to rock soil anchor (rope) tecnical regulations CECS22:2005, complete the pore-forming (aperture is D) of single anchor rod and prepare corresponding anchor pole anti-pulling test testing scheme;
Second step: anchor pole, anchoring section injecting cement paste and the determination with ground interlayer intensity parameter
1) according to anchor pole anti-pulling test testing scheme, choose 6 anchor poles and carry out original position anchor pole pullout tests at the scene, thus mode of failure (anchor pole is along mortar interface sliding rupture or peripherally bed boundary sliding rupture) and the corresponding Ultimate Up-lift Bearing Capacity P of every root anchor pole of anchor pole can be determined 1, P 2, P 3, P 4, P 5, P 6, the limit in mean anti-pulling capacity of anchor pole is determined according to formula (1) for:
P ‾ = P 1 + P 2 + P 3 + P 4 + P 5 + P 6 6 - - - ( 1 )
2) to determine the adhesion strength limiting value under corresponding mode of failure to anchoring depth parameter and limit in mean anti-pulling capacity according to bolt diameter;
1. when anchor bar bundle is along mortar interface sliding rupture, the determination of the adhesion strength limiting value between reinforcing bar and mortar
According to anchor pole limit in mean anti-pulling capacity, the adhesion strength limiting value f between reinforcing bar and mortar sfor:
f s = P ‾ πdL - - - ( 2 )
2. anchor bar bundle peripherally bed boundary sliding rupture time, the determination of the adhesion strength limiting value between mortar and peripheral stratum
According to anchor pole limit in mean anti-pulling capacity, the adhesion strength limiting value f between mortar and peripheral stratum rfor:
f r = P ‾ πDL - - - ( 3 )
3rd step: along the determination of the anchor bar bundle limit pulling test strength that mortar interface destroys
1) k root anchor pole Composite Bolt bundle equivalent diameter determination
According to the diameter of anchor pole and the anchor pole radical of composition anchor bar bundle, calculating k (k>=3) root diameter is respectively its anchored end reinforcing bar of anchor bar bundle of d and the equivalent diameter of grouting contact level (concrete derivation sees its general principles part):
D ‾ = k + 2 2 d - - - ( 4 )
2) determination of anchor bar bundle compound limit resistance to plucking fastening strength
According to the equivalent diameter of anchor bar bundle, anchoring depth and the adhesion strength limiting value between reinforcing bar and mortar, anchor bar bundle compound limit resistance to plucking fastening strength is:
N = π D ‾ L f s = π k + 2 2 dL f s - - - ( 5 )
4th step: the peripherally determination of the anchor bar bundle limit pulling test strength of bed boundary destruction
1) k root anchor pole Composite Bolt bundle boring effective diameter determination
Using the effective diameter of circumcircle diameter during k root anchor pole composition anchor bar bundle as Composite Bolt bundle according to diameter and the anchor pole radical of composition anchor bar bundle of anchor pole, calculate the anchor pole Composite Bolt bundle effective diameter that k (k>=3) root diameter is d respectively for (concrete derive see its general principles part):
2) k root anchor pole Composite Bolt bundle boring effective aperture D edetermination
Technical code for shotcrete rock bolts shore GB 50086-2001 specifies: anchor rod with cement mortar aperture should be greater than body of rod diameter 15mm.According to Technical code for shotcrete rock bolts shore GB 50086-2001, the effective aperture D of anchor bar bundle efor:
D e = d ‾ + b ( b ≥ 15 mm )
3) determination of anchor bar bundle compound limit resistance to plucking fastening strength N ':
According to the adhesion strength limiting value of the effective aperture of anchor bar bundle, anchoring depth and mortar and ground interlayer, determine that anchor bar bundle compound limit resistance to plucking fastening strength is:
N′＝πD eLf r(7)
5th step: the determination of anchor bar bundle compound resistance to plucking reinforcing design intensity
According to the mode of failure of anchor pole, determine corresponding anchor bar bundle limit resistance to plucking fastening strength N or N ', and according to rock soil anchor (rope) tecnical regulations CECS22:2005, by corresponding anchor bar bundle compound limit resistance to plucking fastening strength divided by resistance to plucking safety coefficient K, anchor bar bundle compound resistance to plucking reinforcing design intensity (according to safe class I, II, III, safety coefficient K gets 2.2,2.0,2.0 respectively) can be determined:
N ‾ = N K - - - ( 8 )
Or N ‾ = N ′ K - - - ( 9 ) .
The present invention, according to the mechanism of action of anchor bar bundle and anchor pole, explores contacting and interaction relationship of anchor bar bundle and anchor pole resistance to plucking fastening strength, studies and determine a kind of assay method of anchor bar bundle resistance to plucking fastening strength.According to the parameter that the anti-pulling test of anchor pole obtains, directly determine the resistance to plucking fastening strength design parameters of anchor bar bundle, design for Composite Bolt bundle stabilization works provides a kind of effectively resistance to plucking fastening strength method for designing, has important practical value in the construction of this Reinforcement design in anchor bar bundle.
Accompanying drawing explanation
Fig. 1 is flow chart of the present invention;
Anchored end sketch when Fig. 2 is three anchor pole composition anchor bar bundle;
Anchored end sketch when Fig. 3 is four anchor pole composition anchor bar bundle;
Anchored end sketch when Fig. 4 is five anchor pole composition anchor bar bundle.
Detailed description of the invention
Below in conjunction with drawings and Examples, the present invention is further described.
Theoretical foundation of the present invention and general principle as follows:
Anchor rod anchored as strengthening stratum or the main method utilizing formation strength transferring structure thing pulling force, obtain a wide range of applications in building, water conservancy and construction work.Be in the milk adhesion strength between body (mortar), the adhesion strength of being in the milk between body (mortar) and Rock And Soil of its uplift resistance and anchor rod anchored section of diameter, aperture, anchor rod anchored segment length and anchor pole reinforcing bar and surrounding is relevant.
When anchor pole is along mortar interface sliding rupture, its ultimate pullout capacity formula is: P=π dLf s
When anchor pole together with grouting body along Rock And Soil peripheral stratum interface sliding shear failure time, its ultimate pullout capacity formula is: P=π DLf r
D in formula: the anchoring body diameter of anchor pole
D: the bar diameter of anchor pole
L: the anchoring depth of anchor pole
F r: the adhesion strength limiting value between anchor rod anchored grouting body and Rock And Soil
F s: the adhesion strength limiting value between anchor rod anchored grouting body and reinforcing bar
The supporting and protection structure that anchor bar bundle is derived as anchor pole, it is that the anchor pole of more than three and three bands together, and jointly plays a role.Anchor bar bundle is identical with the effect essence of anchor pole, and it has two kinds of mode of failure:
1), when anchor bar bundle is along mortar interface sliding rupture, now resistance to plucking fastening strength determines primarily of the surface area of reinforcing bar with the effect of grouting body, and its reinforcing bar depends primarily on the girth of anchor bar bundle reinforcing bar and mortar contact surface with the surface area of grouting body effect.The girth of anchor pole is determined by diameter, and its value is asked well, and anchor bar bundle reinforcing bar is not circular with grouting contact level.Its girth changes along with the change of anchor pole radical.The present invention propose k root diameter be the circumferential periphery of its reinforcing bar of anchor bar bundle and the mortar contact surface of the anchor pole composition of d equivalent become diameter be anchor pole and the circumferential periphery of mortar contact surface, explored with the relation of d, derivation is as follows:
3 anchor pole Composite Bolt bundle anchored end sketches as Fig. 2, anchored end girth then equivalent diameter D ‾ = 2.5 d
4 anchor pole Composite Bolt bundle anchored end sketches as Fig. 3, anchored end girth then equivalent diameter D ‾ = 3 d
5 anchor pole Composite Bolt bundle anchored end sketches as Fig. 4, anchored end girth then equivalent diameter D ‾ = 3.5 d
......
K root anchor pole Composite Bolt bundle anchored end girth by that analogy then equivalent diameter
Under this mode of failure, anchor bar bundle compound limit resistance to plucking fastening strength is according to formula calculate.
2) anchor bar bundle together with grouting body along Rock And Soil bed boundary slippage shear failure, now resistance to plucking fastening strength determines primarily of the surface area acted between grouting body and Rock And Soil, its surface area depends primarily on the girth at the peripheral Rock And Soil interface of anchor bar bundle anchoring body, and the girth at peripheral Rock And Soil interface is determined by its circumcircle diameter, using its circumcircle diameter as effective diameter its effective diameter can try to achieve according to anchored end sketch geometric figure relation, concrete derivation is as follows:
3 anchor pole Composite Bolt bundle anchored end sketches as Fig. 2, according to its geometric figure relation, its circumcircle radius close with the radius r of single anchor rod and be:
Therefore, its effective diameter close with the diameter d of single anchor rod and be:
4 anchor pole Composite Bolt bundle anchored end sketches as Fig. 3, according to its geometric figure relation, its circumcircle radius close with the radius r of single anchor rod and be:
Therefore, its effective diameter close with the diameter d of single anchor rod and be:
5 anchor pole Composite Bolt bundle anchored end sketches as Fig. 4, according to its geometric figure relation, its circumcircle radius close with the radius r of single anchor rod and be:
Therefore, its effective diameter close with the diameter d of single anchor rod and be:
......
K root anchor pole Composite Bolt bundle circumcircle radius by that analogy close with the radius r of single anchor rod and be:
Therefore, its effective diameter close with the diameter d of single anchor rod and be:
Technical code for shotcrete rock bolts shore GB 50086-2001 specifies: anchor rod with cement mortar aperture should be greater than body of rod diameter 15mm, according to Technical code for shotcrete rock bolts shore GB 50086-2001, the effective aperture D of anchor bar bundle efor:
D e = d ‾ + b ( b ≥ 15 mm ) .
Under this mode of failure, anchor bar bundle compound limit resistance to plucking fastening strength is according to formula N '=π D elf r=π D elf rcalculate.
After determining the anchor bar bundle compound limit resistance to plucking fastening strength that corresponding mode of failure is corresponding, set a resistance to plucking safety coefficient K as safety stock also should to anchor bar bundle anchoring body, according to rock soil anchor (rope) tecnical regulations CECS22:2005, by corresponding anchor bar bundle compound limit resistance to plucking fastening strength divided by resistance to plucking safety coefficient K, its resistance to plucking reinforcing design intensity can be determined.
Embodiment 1:
In order to better the present invention is described, be described in detail for certain stock ground excavation rock side slope below.This stock ground landform, complex geologic conditions, according to exploitation planning, stock ground will form the excavation slope of high 300m, the shaping whole slope gradient nearly 1: 0.40 after excavation after excavation.After Rock Mass Unloading, will there is lax distortion in slope rock mass gradually.Slope excavation span is comparatively large, and supporting requires higher, according to slope stability analysis conclusion, intends taking anchor bar bundle supporting measure to this stock ground excavation slope.Below for this project, be described in detail for calculating anchor pole Composite Bolt bundle resistance to plucking fastening strength.Specific embodiments and process as follows:
The first step: choosing and the determination of anti-pulling test scheme of bolt design parameters
According to geological conditions and engineering practice, design and determine that often restrainting anchor bar bundle adopts diameter 25mm indented bars composition, anchoring depth is 1m, according to anchor pole anti-pulling test testing scheme, and foundation single anchor rod diameter and effectively anchoring strength parameter and rock soil anchor (rope) tecnical regulations CECS22:2005, complete the pore-forming (aperture 40mm) of single anchor rod and prepare corresponding anchor pole anti-pulling test testing scheme.
Second step: anchor pole, anchoring section injecting cement paste and the determination with ground interlayer intensity parameter
1) according to anchor pole anti-pulling test testing scheme, choose 6 anchor poles and carry out original position anchor pole pullout tests at the scene, thus the mode of failure determining anchor pole is anchor bar bundle along mortar interface sliding rupture and the corresponding Ultimate Up-lift Bearing Capacity 130KN of every root anchor pole, 120KN, 160KN, 150KN, 160KN, 180KN.The Ultimate Up-lift Bearing Capacity of anchor pole is:
P = 130 + 120 + 160 + 150 + 160 + 180 6 = 150 KN
2) the adhesion strength limiting value under corresponding mode of failure is determined according to bolt diameter and anchoring depth parameter and Ultimate Up-lift Bearing Capacity.
Because anchor bar bundle mode of failure is along mortar interface sliding rupture, the adhesion strength limiting value between reinforcing bar and mortar is
f s = P πdL = 150 3.14 × 25 × 1 = 1.91 Mpa
3rd step: along the determination of the anchor bar bundle limit pulling test strength that mortar interface destroys
1) determination of k root anchor pole Composite Bolt bundle equivalent diameter
According to formula (4) calculate respectively k (k>=3) root diameter be the anchor pole of 25mm closely tie up composition anchor bar bundle time its anchor bar bundle anchored end and grouting contact level equivalent diameter
D ‾ = k + 2 2 d - - - ( 4 )
Three anchor pole Composite Bolt bundles, namely during k=3,
Four anchor pole Composite Bolt bundles, namely during k=4,
Five anchor pole Composite Bolt bundles, namely during k=5,
......
2) k root anchor pole Composite Bolt bundle limit resistance to plucking fastening strength is determined according to formula (5);
N = π D ‾ L f s = π k + 2 2 dL f s - - - ( 5 )
Three anchor pole Composite Bolt bundle limit resistance to plucking fastening strengths are N=374.84KN
Four anchor pole Composite Bolt bundle limit resistance to plucking fastening strengths are N=449.81KN
Five anchor pole Composite Bolt bundle limit resistance to plucking fastening strengths are N=524.77KN
......
4th step: the determination of anchor bar bundle compound resistance to plucking reinforcing design intensity
According to the mode of failure that anchor pole destroys along mortar interface, determine corresponding anchor bar bundle limit resistance to plucking fastening strength, and determine that resistance to plucking safety coefficient K is 2 according to rock soil anchor (rope) tecnical regulations CECS22:2005.K (k >=3) root anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity is calculated respectively according to formula (8).
N ‾ = N K - - - ( 8 )
Three anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity are
Four anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity are
Five anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity are
......
Embodiment 2:
In order to better the present invention is described, be described in detail for certain rock matter high cutting-slope below.This cuts slope is the high cut slope building highway formation, cuts slope height 20m ~ 26m, slope angle 65 °, due to building and local resident's quarrying of highway, cause body local, slope to form cutting, often there is local avalanche in part rock mass residual on the body of slope, and likely along face, rock stratum, bedding glide occurs.This project supporting requires higher, in line with the principle of safety, economy, constructability, the method intending adopting anchor bar bundle to reinforce is reinforced further to this high cutting-slope, below for this project, is described in detail for calculating anchor pole Composite Bolt bundle resistance to plucking fastening strength.Specific embodiments and process as follows:
The first step: choosing and the determination of anti-pulling test scheme of bolt design parameters
According to geological conditions and engineering practice, design and determine that often restrainting anchor bar bundle adopts diameter 32mm indented bars composition, anchoring depth is 1m, according to anchor pole anti-pulling test testing scheme, and foundation single anchor rod diameter and effectively anchoring strength parameter and rock soil anchor (rope) tecnical regulations CECS22:2005, complete the pore-forming (aperture 47mm) of single anchor rod and prepare corresponding anchor pole anti-pulling test testing scheme.
Second step: anchor pole, anchoring section injecting cement paste and the determination with ground interlayer intensity parameter
1) according to anchor pole anti-pulling test testing scheme, choose 6 anchor poles and carry out original position anchor pole pullout tests at the scene, thus the mode of failure determining anchor pole is anchor bar bundle peripherally bed boundary sliding rupture and the corresponding Ultimate Up-lift Bearing Capacity 180KN of every root anchor pole, 160KN, 150KN, 180KN, 170KN, 180KN.The Ultimate Up-lift Bearing Capacity of anchor pole is:
P = 180 + 160 + 150 + 180 + 170 + 180 6 = 170 KN
2) to determine the adhesion strength limiting value under corresponding mode of failure to anchoring depth parameter and Ultimate Up-lift Bearing Capacity according to the pore-forming aperture of anchor pole.
Because anchor bar bundle mode of failure is peripherally bed boundary sliding rupture, the adhesion strength limiting value between mortar and peripheral stratum is
f r = P πDL = 170 3.14 × 47 × 1 = 1.15 Mpa
3rd step: the peripherally determination of the anchor bar bundle limit pulling test strength of bed boundary destruction
1) k root anchor pole Composite Bolt bundle boring effective diameter determination
According to formula (6) calculate respectively k (k>=3) root diameter be the anchor pole of 32mm closely tie up composition anchor bar bundle time its anchor bar bundle effective diameter
Three anchor pole Composite Bolt bundles, namely during k=3,
Four anchor pole Composite Bolt bundles, namely during k=4,
Five anchor pole Composite Bolt bundles, namely during k=5,
......
3) k root anchor pole Composite Bolt bundle boring effective aperture D edetermination
According to Technical code for shotcrete rock bolts shore GB 50086-2001, the effective aperture D of anchor bar bundle eget and be greater than anchor bar bundle effective diameter namely b gets 15mm.
Three anchor pole Composite Bolt bundles, namely during k=3, D e=83.96mm
Four anchor pole Composite Bolt bundles, namely during k=4, D e=92.248mm
Five anchor pole Composite Bolt bundles, namely during k=5, D e=101.432mm
......
2) k root anchor pole Composite Bolt bundle limit resistance to plucking fastening strength is determined according to formula (7);
N′＝πD eLf r(7)
Three anchor pole Composite Bolt bundle limit resistance to plucking fastening strengths are N '=303.18KN
Four anchor pole Composite Bolt bundle limit resistance to plucking fastening strengths are N '=333.11KN
Five anchor pole Composite Bolt bundle limit resistance to plucking fastening strengths are N '=366.27KN
......
4th step: the determination of anchor bar bundle compound resistance to plucking reinforcing design intensity
According to the anchor pole peripherally mode of failure that destroys of bed boundary, determine corresponding anchor bar bundle limit resistance to plucking fastening strength, and determine that resistance to plucking safety coefficient K is 2 according to rock soil anchor (rope) tecnical regulations CECS22:2005.K (k >=3) root anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity is calculated respectively according to formula (9).
N ‾ = N ′ K - - - ( 9 )
Three anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity are
Four anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity are
Five anchor pole Composite Bolt bundle resistance to plucking reinforcing design intensity are
......
By reference to the accompanying drawings the specific embodiment of the present invention is described although above-mentioned; but not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various amendment or distortion that creative work can make still within protection scope of the present invention.

Claims (5)

1. an assay method for anchor bar bundle compound resistance to plucking reinforcing design intensity, is characterized in that, comprising:
The first step: determine choosing and anti-pulling test scheme of bolt design parameters;
Second step: determine anchor pole, anchoring section injecting cement paste and with ground interlayer intensity parameter;
1) according to anchor pole anti-pulling test testing scheme, the limit in mean anti-pulling capacity of anchor pole along mortar interface sliding rupture or peripherally bed boundary sliding rupture is determined
2) the adhesion strength limiting value under the corresponding mode of failure of anchor pole is determined;
1., when anchor bar bundle is along mortar interface sliding rupture, the adhesion strength limiting value f between reinforcing bar and mortar is determined z;
2. anchor bar bundle peripherally bed boundary sliding rupture time, determine the adhesion strength limiting value f between mortar and peripheral stratum r;
3rd step: along the determination of the anchor bar bundle limit pulling test strength that mortar interface destroys
1) k root anchor pole Composite Bolt bundle equivalent diameter determination
According to the diameter d of anchor pole and the anchor pole radical k of composition anchor bar bundle, the equivalent diameter of its anchored end reinforcing bar of anchor bar bundle and grouting contact level for,
D ‾ = k + 2 2 d - - - ( 4 )
Its, middle k >=3;
2) determine that anchor bar bundle compound limit resistance to plucking fastening strength is:
N = π D ‾ L f s = π k + 2 2 dL f s - - - ( 5 )
Wherein, L is anchor rod anchored segment length;
4th step: the peripherally determination of the anchor bar bundle limit pulling test strength of bed boundary destruction
1) k root anchor pole Composite Bolt bundle boring effective diameter determination
Using the effective diameter of circumcircle diameter during k root anchor pole composition anchor bar bundle as Composite Bolt bundle according to the diameter d of anchor pole and the anchor pole radical k of composition anchor bar bundle, Composite Bolt bundle effective diameter for:
Wherein, k >=3;
2) k root anchor pole Composite Bolt bundle boring effective aperture D edetermination
The effective aperture D of anchor bar bundle efor: wherein b>=15mm;
3) determination of anchor bar bundle compound limit resistance to plucking fastening strength N ':
According to the adhesion strength limiting value of the effective aperture of anchor bar bundle, anchoring depth and mortar and ground interlayer, determine that anchor bar bundle compound limit resistance to plucking fastening strength is:
N＝πD eLf r(7)
5th step: the determination of anchor bar bundle compound resistance to plucking reinforcing design intensity
According to the mode of failure of anchor pole, determine corresponding anchor bar bundle limit resistance to plucking fastening strength N or N ', and according to rock soil anchor or rope tecnical regulations CECS22:2005, by corresponding anchor bar bundle compound limit resistance to plucking fastening strength divided by resistance to plucking safety coefficient K, anchor bar bundle compound resistance to plucking reinforcing design intensity can be determined:
N ‾ = N K - - - ( 8 )
Or N ‾ = N ′ K - - - ( 9 ) ;
According to safe class I, II, III, safety coefficient K gets 2.2,2.0,2.0 respectively.
2. the assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity as claimed in claim 1, it is characterized in that, in the described first step, according to geological conditions and engineering practice, design and determine to form the bolt diameter d of anchor bar bundle and anchor rod anchored segment length L, and according to rock soil anchor or rope tecnical regulations CECS22:2005, the pore-forming and the aperture that complete single anchor rod are D and prepare corresponding anchor pole anti-pulling test testing scheme.
3. the assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity as claimed in claim 1, it is characterized in that, described second step the 1st) in, according to anchor pole anti-pulling test testing scheme, choose 6 anchor poles and carry out original position anchor pole pullout tests at the scene, thus can determine that the mode of failure of anchor pole and anchor pole are along mortar interface sliding rupture or peripherally bed boundary sliding rupture and the corresponding Ultimate Up-lift Bearing Capacity P of every root anchor pole 1, P 2, P 3, P 4, P 5, P 6; Determine that the limit in mean anti-pulling capacity of anchor pole is according to formula (1):
P ‾ = P 1 + P 2 + P 3 + P 4 + P 5 + P 6 6 - - - ( 1 ) .
4. the assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity as claimed in claim 1, is characterized in that, the adhesion strength limiting value f between described reinforcing bar and mortar sfor:
f s = P ‾ πdL - - - ( 2 )
Wherein, the diameter of d anchor pole, L is anchor rod anchored segment length.
5. the assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity as claimed in claim 1, is characterized in that, the adhesion strength limiting value f between described mortar and peripheral stratum rfor:
f r = P ‾ πDL - - - ( 3 )
Wherein, D is the pore-forming aperture of single anchor rod, and L is anchor rod anchored segment length.
CN201410787650.5A 2014-12-17 2014-12-17 The assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity Expired - Fee Related CN104532835B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410787650.5A CN104532835B (en) 2014-12-17 2014-12-17 The assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410787650.5A CN104532835B (en) 2014-12-17 2014-12-17 The assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity

Publications (2)

Publication Number Publication Date
CN104532835A true CN104532835A (en) 2015-04-22
CN104532835B CN104532835B (en) 2016-01-20

Family

ID=52848443

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410787650.5A Expired - Fee Related CN104532835B (en) 2014-12-17 2014-12-17 The assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity

Country Status (1)

Country Link
CN (1) CN104532835B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107941620A (en) * 2017-11-16 2018-04-20 山东建筑大学 Underground engineering bolt-mesh-spurting supporting structural mechanical property test evaluation device and method
CN117807690A (en) * 2024-03-01 2024-04-02 济南轨道交通集团有限公司 Method and system for selecting bonding strength of anchoring body of rock-soil slope or foundation pit

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436923A (en) * 1966-07-07 1969-04-08 Atlas Copco Ab Method and equipment for making tension anchors
US3738071A (en) * 1970-08-21 1973-06-12 Dyckerhoff & Widmann Ag Tension element for constructing a prestressed tension anchor in the ground
CN202401478U (en) * 2012-03-06 2012-08-29 徐金 Anti-floating anchor bolt bundle
CN103321234A (en) * 2013-07-08 2013-09-25 中国水电顾问集团成都勘测设计研究院 Load-bearing structure built on high slope or geological complex area and constructing method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436923A (en) * 1966-07-07 1969-04-08 Atlas Copco Ab Method and equipment for making tension anchors
US3738071A (en) * 1970-08-21 1973-06-12 Dyckerhoff & Widmann Ag Tension element for constructing a prestressed tension anchor in the ground
CN202401478U (en) * 2012-03-06 2012-08-29 徐金 Anti-floating anchor bolt bundle
CN103321234A (en) * 2013-07-08 2013-09-25 中国水电顾问集团成都勘测设计研究院 Load-bearing structure built on high slope or geological complex area and constructing method thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107941620A (en) * 2017-11-16 2018-04-20 山东建筑大学 Underground engineering bolt-mesh-spurting supporting structural mechanical property test evaluation device and method
CN107941620B (en) * 2017-11-16 2024-01-26 山东建筑大学 Mechanical property test evaluation device and method for underground engineering anchor net spray supporting structure
CN117807690A (en) * 2024-03-01 2024-04-02 济南轨道交通集团有限公司 Method and system for selecting bonding strength of anchoring body of rock-soil slope or foundation pit

Also Published As

Publication number Publication date
CN104532835B (en) 2016-01-20

Similar Documents

Publication Publication Date Title
CN102518135B (en) Horizontal jet grouting soil anchor and castinplace pile Composite Foundation Pit supporting construction engineering method
CN202466594U (en) Horizontal jet grouting soil anchoring and cast-in-place pile compound foundation pit supporting structure
CN103526773B (en) Cantilever type vertical anchor rod composite retaining wall and design and construction method thereof
CN103233473B (en) Many ribs of high polymer stake grouting method
CN102518453A (en) Quick tunnel-entrance construction method for bias-pressure shallow-buried or single-pressure tilting arenaceous loess tunnels
CN207633352U (en) A kind of slope reinforcement structure for rapid rescue construction
CN103147442A (en) Ultra-deep foundation pit press-grouting pile and prestressed anchor combined supporting construction method
JP6279945B2 (en) Soil surface anti-slip method for earth structure
CN209924998U (en) Shallow earthing shield tunnel is worn road reinforcement protection architecture down
CN110374111B (en) Slope releasing and steel pipe pile anchor cooperative supporting system
CN108385715A (en) A kind of assembled stake arch combination retaining wall and its construction method
CN105839651A (en) Roadbed slope assembly type deformation self-adaptive protective framework and splicing method thereof
CN203049443U (en) High level trestle structure arranged on steep bare rock of deepwater torrent unsheathed layer
CN111173006B (en) Ecological slope protection method for reinforcing hilly soil by combining permeable retaining wall and sounding type bar planting belt
CN204000925U (en) Prefabricated diaphragm wall
JP6370645B2 (en) Slope stabilization method for seismic and rainproof measures of earth structures by using pressure injection type rod-shaped reinforcements
CN205653804U (en) Slope assembled warp self -adaptation protection skeleton
CN104532835B (en) The assay method of anchor bar bundle compound resistance to plucking reinforcing design intensity
CN209211459U (en) Skirt piles are gone along with sb. to guard him in a kind of buried subway station PBA
CN102660959B (en) Pulling reinforcement method for internal fissure of dangerous rock
CN205576990U (en) Cross section and wear bridge pier tunnel slip casting supporting construction
CN203361182U (en) Unequal-length bottom-expanded rock anchor pile of power transmission pole tower
CN203373753U (en) Pile anchor retaining wall concrete anchor cable top beam structure of foundation ditches
CN201567579U (en) Foundation pit supporting structure of gantry pine pile anchored rod
CN206204942U (en) Reinforcement cutting side slope's pulling force type stock

Legal Events

Date Code Title Description
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20160120

Termination date: 20161217