CN101487265B - Expansion type support management method for slope ground partial potential safety hazard section - Google Patents

Abstract

The invention discloses an expansion-style support treatment method used for the local risk zones of slope rock. A plurality of axial parallel expansion-style plain concrete anchor rods are arranged in the risk zones of the slope rock. The invention has the beneficial effects that arranging the expansion-style plain concrete anchor rods can perform the side expansion effect of the anchor rods so as to extrude the risk zones of the rocks, enhance the integral intensity of the rocks in the risk zone and effectively support the local risk zones of the slope rock.

Description

Slope ground partial potential safety hazard district intumescent supports the improvement method

Technical field

The present invention relates to a kind of geotechnical slope diaster prevention and control technology, relate in particular to a kind of slope ground partial potential safety hazard district intumescent and support the improvement method.

Background technology

China's mountain and hill accounts for territory total area more than 2/3, along with building fast and mountain area city-building high speed development of China Higher level highway, ground high slope quantity is increasing, highly increasing, the gradient is more and more steeper, the geology safety problem is outstanding day by day, geomorphic feature referring to Fig. 1,2, two kinds of typical side slope disaster hidden danger.The great disaster example of some that cause, as on November 20th, 2007, huge collapse hazard takes place in the national highway 318 line K1405 side slopes on stockaded village, Gaoyang, Badong County, Hubei Province, the passenger vehicle that license plate number is Hubei Province Q20684 is buried by the avalanche body, and 31 people are all wrecked in the car, and this collapse hazard source is positioned at above 34m place, road surface, the avalanche body is along the about 35m of length of cliff trend, high about 24m, about thick 5m, cumulative volume 4512m ³, fall at the remaining block volume 500m on road surface ³About, the crag body is made up of limestone; Occurring in Wulong County, Chongqing City north of the city height May 1 calendar year 2001 cuts the slope and strides and collapse that (height is cut sloping vertical height 46.8m, the wide 55.2m of leading edge, trailing edge width 25～30m, about 1.6 ten thousand m3 of volume) incident, the 9 layers of resident's building in Building 1 moment is buried by destruction, cause 79 people's death, 4 people injured, shock the world.Rough estimates show, the Chongqing City over nearly 10 years highway established high slope cumulative length along the line reached about 300km, threatening more than 500 kilometer highway communication transportation safety.Obviously, effectively administer high slope, have necessity, urgency.

In the preventing and controlling of ground high slope, because there is significant difference in the ground safety condition of high slope different parts, the key of control side slope safety condition is ground partial potential safety hazard district in the side slope.Therefore, under the condition that China has quite modest financial resources at present, implement effective improvement in high slope ground partial potential safety hazard district, have important practical significance and economic implications.

So far, obtained important science and technology progress both at home and abroad in side slope research and aspect preventing and treating, national standard " building slope engineering legislation " (GB50330-2002) has proposed packaged technology to height less than effective control of the geotechnical slope of 20m, but, for the geotechnical slope that highly surpasses 20m, this standard clearly proposes " need carry out special demonstration ", and, the governing problem in slope ground partial potential safety hazard district is not provided any prophylactico-therapeutic measures suggestion.

Summary of the invention

The present invention proposes a kind of slope ground partial potential safety hazard district intumescent and support the improvement method:, implant the intumescent plain concrete anchor pole of many row's axially parallels in the potential safety hazard district of the slope ground that defines.

The diameter d span of expansion morph concrete anchor rod is 15～20cm, expansion rate r=30～35% of intumescent plain concrete anchor pole, diameter D=(1+r) d after intumescent plain concrete anchor pole expands, the length l=3～5m of intumescent plain concrete anchor pole.

Press the quincuncial pile form and lay intumescent plain concrete anchor pole, the spacing of each intumescent plain concrete anchor pole is a * b:

$a\&times;b=\frac{{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="H2009101031951E00023.png,H2009101031951E00031.png"\; state="\{\{state\}\}">K</figure-callout>}}_1+\sqrt{{\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="H2009101031951E00013.png,H2009101031951E00021.png"\; state="\{\{state\}\}">K</figure-callout>}}_2^2+4K_1{K}_3}}{2{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="H2009101031951E00023.png,H2009101031951E00031.png"\; state="\{\{state\}\}">K</figure-callout>}}_1}$

In the formula, a is for moving towards the center distance (m) of the adjacent intumescent plain concrete of direction anchor pole along side slope; B is the center distance (m) along the adjacent intumescent plain concrete of slope height direction anchor pole;

${\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="H2009101031951E00023.png,H2009101031951E00031.png"\; state="\{\{state\}\}">K</figure-callout>}}_1=\frac{4P}{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="BD"\; filenames="H2009101031951E00013.png,H2009101031951E00021.png"\; state="\{\{state\}\}">BD</figure-callout>}}^2};$ K ₂=E ' _{S soil}K ₃=π D ²(E _{The s concrete}-E ' _{S soil});

Wherein, P is the required supporting force in secure topical hidden danger district, P=σ _Max-γ z ₀, σ _MaxThe maximum crushing stress (kPa) that is subjected to for top, local ground potential safety hazard district; γ is the average unit weight (kN/m of slope ground medium ³); z ₀Be the vertical height (m) of hole to bench edge distance from top, ground potential safety hazard district; B is the height (m) of slope ground potential safety hazard district along the high direction in slope;

E _{S soil}Modulus of compressibility (kPa) for the potential safety hazard district soil body before administering; E ' _{S soil}For administering the modulus of compressibility (kPa) of potential safety hazard district, the back soil body; E _{The s concrete}Modulus of elasticity (kPa) for intumescent plain concrete anchor pole;

e ₁Initial void ratio for the ground potential safety hazard district soil body; e ₂For implementing intumescent, ground partial potential safety hazard district supports the void ratio of administering the back soil body;

Calculate e according to following formula ₂:

$e_2=\frac{4\mathrm{BL}{e}_1-\mathrm{\&pi;}(1+e_1)(D-d)}{4\mathrm{BL}+\mathrm{\&pi;}(1+e_1)(D-d)}$

In the formula: B is the height (m) of ground potential safety hazard district along the high direction in slope; L is ground potential safety hazard district moves towards direction along side slope a length (m); D is the diameter (m) of expansion morph concrete anchor rod.

According to the result of calculation of a * b, determine the value of a, b respectively, general a, b get equidistantly, promptly get a=b;

If a, b during greater than 1.5m, get 1.5m, if a, b during less than 0.5m, reduce intumescent plain concrete anchor pole expand before diameter d, recomputate a * b.

The row who implants the required intumescent plain concrete anchor pole in potential safety hazard district counts n and columns m:

$n\&GreaterEqual;\left[\frac{B}{b}\right]$

$m\&GreaterEqual;\left[\frac{L}{a}\right]$

Wherein, [] is for rounding symbol; A is for moving towards the center distance (m) of the adjacent intumescent plain concrete of direction anchor pole along side slope; B is the center distance (m) along the adjacent intumescent plain concrete of slope height direction anchor pole; B is the height (m) of ground potential safety hazard district along the high direction in slope; L is ground potential safety hazard district moves towards direction along side slope a length (m).

The method of expandable implant type plain concrete anchor pole is as follows:

1) manually removes the surperficial surface dust in slope ground potential safety hazard district;

2), lay bolthole by anchor pole position, the spacing of design in the potential safety hazard district of slope ground;

3) hole clear hole by designing requirement in the bolthole position;

4) preparation intumescent dilution concrete is in the injection hole, till the aperture has concrete slurry to overflow.

During implantation, each bolthole is parallel along the hole direction of principal axis, and bolthole hole direction of principal axis is vertical with the soil table, hole depth 3～5m, aperture 15～20cm; During intumescent dilution concrete injection hole, guarantee that the anchor pole slurry is full.The cement expansive material volume is 13～16% in the intumescent dilution concrete, and intumescent dilutes concrete swollen account rate r=30～35%.

Useful technique effect of the present invention is: by laying intumescent plain concrete anchor pole, hidden danger district geotechnical body is pushed in the lateral expansion effect of performance anchor pole, improves the bulk strength of geotechnical body in this zone, realizes effective support in slope ground partial hidden danger district.

Description of drawings

Fig. 1,2, two kinds of typical geomorphic feature photos in the side slope disaster: the mud stone height is cut slope (Fig. 1), and residual slide rock object height is cut slope (Fig. 2);

Fig. 3, slope ground partial potential safety hazard district schematic diagram;

Fig. 4, potential safety hazard district intumescent plain concrete anchor pole is arranged profile;

Fig. 5, potential safety hazard district intumescent plain concrete anchor pole plane of arrangement figure;

Fig. 6, intumescent plain concrete anchor pole is arranged dimensional drawing;

Fig. 7, intumescent plain concrete anchor pole stereogram;

Among the figure, intumescent plain concrete anchor pole 1, potential safety hazard district 2, B is the height of ground potential safety hazard district along the high direction in slope; L is ground potential safety hazard district moves towards direction along side slope a length; A is for moving towards the center distance of the adjacent intumescent plain concrete of direction anchor pole along side slope; B is the center distance along the adjacent intumescent plain concrete of slope height direction anchor pole; D is intumescent plain concrete bolt diameter before expanding; D is a diameter after intumescent plain concrete anchor pole expands;

The specific embodiment

Referring to Fig. 3, slope ground potential safety hazard district 2 is meant after geotechnical slope forms, owing to lose lateral support, the high pressure stress district that surpasses the rock soil medium allowable bearing that the adjustment of side slope internal stress forms, this regional rock soil medium is easy to produce rheodestruction and exogenic force erosion damage, and then jeopardizes the safety of whole side slope.

Operating principle of the present invention is as follows:

After adopting method of the present invention that slope ground partial potential safety hazard district 2 is administered, referring to Fig. 4, intumescent plain concrete anchor pole 1 mainly expands along side direction (anchor pole radially), and then compacted ground partial potential safety hazard district 2 rock soil medium, makes its void ratio by the e before administering ₁Be reduced to the e after the improvement ₂Slope ground potential safety hazard district 2 after compacted, rock soil medium becomes ground-plain concrete pile complex, its physical and mechanical property can be significantly improved, and satisfies its top ground maximum crushing stress demand of carrying, realizes that slope ground partial potential safety hazard district 2 intumescents support management goal.

Carry out the parameters design before the construction earlier, the parameter designing step is as follows:

1) clearly defined the scope in slope ground partial potential safety hazard district 2 by numerical simulation and field monitoring method, and the average unit weight γ and the maximum crushing stress σ of ground potential safety hazard district 2 top geotechnical body _Max, ground potential safety hazard district 2 soil body initial void ratio e ₁With modulus of compressibility E _{S soil}, the plain concrete material elastic modulus E _{The s concrete}Be given value etc. parameter.

2) draft the preceding diameter d of intumescent plain concrete anchor pole 1 expansion and get 15～20cm, intumescent plain concrete anchor pole 1 length 3～5m (hole depth when also promptly holing), the concrete material of cast anchor pole adopts the cement of C20 label, standard mix according to concrete material, add 13～16% expansion agent, so get expansion rate r=30～35%, intumescent plain concrete anchor pole 1 expansion back diameter D then arranged

D＝(1+r)d

3) the physical dimension B and the L in measurement slope ground potential safety hazard district 2, the vertical height z of measurement ground potential safety hazard district 2 top geotechnical body ₀, calculate the void ratio e that ground potential safety hazard district 2 lays the intumescent plain concrete anchor pole 1 back soil body by following formula ₂,

$e_2=\frac{4\mathrm{BL}{e}_1-\mathrm{\&pi;}(1+e_1)(D-d)}{4\mathrm{BL}+\mathrm{\&pi;}(1+e_1)(D-d)}$

Wherein, B is the height of ground potential safety hazard district 2 along sloping high direction; L is ground potential safety hazard district 2 moves towards direction along side slope a length.

4) the spacing a and the b of calculating intumescent plain concrete anchor pole 1, calculating formula is

$a\&times;b=\frac{{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="H2009101031951E00023.png,H2009101031951E00031.png"\; state="\{\{state\}\}">K</figure-callout>}}_1+\sqrt{{\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="H2009101031951E00013.png,H2009101031951E00021.png"\; state="\{\{state\}\}">K</figure-callout>}}_2^2+4K_1{K}_3}}{2{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="H2009101031951E00023.png,H2009101031951E00031.png"\; state="\{\{state\}\}">K</figure-callout>}}_1}$

${\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="H2009101031951E00023.png,H2009101031951E00031.png"\; state="\{\{state\}\}">K</figure-callout>}}_1=\frac{4P}{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="BD"\; filenames="H2009101031951E00013.png,H2009101031951E00021.png"\; state="\{\{state\}\}">BD</figure-callout>}}^2}$

K ₂=E ' _{S soil}

K ₃=π D ²(E _{The s concrete}-E ' _{S soil})

E ' _{S soil}For administering the modulus of compressibility (kPa) of potential safety hazard district, back 2 soil bodys;

According to the result of calculation of a * b, can determine the value of a, b respectively, generally getting equidistantly is a=b; During as a=b and greater than 1.5m, get 1.5m; During as a=b and less than 0.5m, reduce the preceding diameter d of intumescent plain concrete anchor pole 1 expansion, recomputate a * b.

The row of the intumescent plain concrete anchor pole that implantation potential safety hazard district is required counts n and columns m is determined by following formula:

$n\&GreaterEqual;\left[\frac{B}{b}\right]$

$m\&GreaterEqual;\left[\frac{L}{a}\right]$

Wherein, [] is for rounding symbol; A is for moving towards the center distance (m) of the adjacent intumescent plain concrete of direction anchor pole along side slope; B is the center distance (m) along the adjacent intumescent plain concrete of slope height direction anchor pole; B is the height (m) of ground potential safety hazard district along the high direction in slope; L is ground potential safety hazard district moves towards direction along side slope a length (m).

Parameter designing intact half can be constructed, and referring to Fig. 5,6, concrete construction sequence is as follows:

1) manually removes the surperficial surface dust in slope ground potential safety hazard district 2;

2) in the potential safety hazard district 2 of slope ground, lay a plurality of boltholes by the quincuncial pile form;

3) hole clear hole by designing requirement in the bolthole position;

4) preparation intumescent dilution concrete is in the injection hole, till the aperture has concrete slurry to overflow (concrete slurry is intumescent plain concrete anchor pole 1 after solidifying); Guarantee that intumescent plain concrete anchor pole 1 slurry is full.

Claims (7)

1. a slope ground partial potential safety hazard district intumescent supports the improvement method, it is characterized in that: in the potential safety hazard district (2) of the slope ground that defines, implant the intumescent plain concrete anchor pole (1) of many row's axially parallels;

Wherein, press the quincuncial pile form and lay intumescent plain concrete anchor pole (1), the spacing of each intumescent plain concrete anchor pole (1) is a * b:

$a\&times;b=\frac{K_1+\sqrt{K_2^2+{4K}_1{K}_3}}{{2K}_1}$

In the formula, a is for moving towards the center distance of the adjacent intumescent plain concrete of direction anchor pole (1) along side slope, and unit is m; B is the center distance along the adjacent intumescent plain concrete of slope height direction anchor pole (1), and unit is m;

$K_1=\frac{4P}{{\mathrm{\&pi;BD}}^2};$

Wherein, P is the required supporting force in secure topical hidden danger district, P=σ _Max-γ z ₀, σ _MaxBe the maximum crushing stress that top, local ground potential safety hazard district (2) is subjected to, unit is kPa; γ is the average unit weight of slope ground medium, and unit is kN/m ³z ₀Be the vertical height of hole to bench edge distance from top, ground potential safety hazard district (2), unit is m; B is the height of slope ground potential safety hazard district (2) along sloping high direction, and unit is m;

E _{S soil}Be the modulus of compressibility of potential safety hazard district (2) soil body before administering, unit is kPa;

For administering the modulus of compressibility of potential safety hazard district (2), the back soil body, unit is kPa; E _{The s concrete}Be the modulus of elasticity of intumescent plain concrete anchor pole (1), unit is kPa;

e ₁Initial void ratio for ground potential safety hazard district (2) soil body; e ₂For implementing intumescent, ground partial potential safety hazard district (2) supports the void ratio of administering the back soil body;

Calculate e according to following formula ₂:

$e_2=\frac{{4\mathrm{BLe}}_1-\mathrm{\&pi;}(1+e_1)(D-d)}{4\mathrm{BL}+\mathrm{\&pi;}(1+e_1)(D-d)}$

In the formula: B is the height of ground potential safety hazard district (2) along sloping high direction, and unit is m; To be ground potential safety hazard district (2) move towards the length of direction along side slope to L, and unit is m; D is the diameter of intumescent plain concrete anchor pole (1), and unit is m; D is a diameter after intumescent plain concrete anchor pole (1) expands.

2. slope ground partial potential safety hazard according to claim 1 district intumescent supports the improvement method, it is characterized in that: the diameter d span of intumescent plain concrete anchor pole (1) is 0.15～0.20m, expansion rate r=30～35% of intumescent plain concrete anchor pole (1), diameter D=(1+r) d after intumescent plain concrete anchor pole (1) expands, the length l=3～5m of intumescent plain concrete anchor pole (1).

3. slope ground partial potential safety hazard according to claim 1 district intumescent supports the improvement method, it is characterized in that:

According to the result of calculation of a * b, determine the value of a, b respectively, general a, b get equidistantly, promptly get a=b;

If a, b during greater than 1.5m, get 1.5m, if a, b during less than 0.5m, reduce intumescent plain concrete anchor pole (1) expand before diameter d, recomputate a * b.

4. slope ground partial potential safety hazard according to claim 1 district intumescent supports the improvement method, it is characterized in that: the row who implants the required intumescent plain concrete anchor pole (1) in potential safety hazard district counts n and columns m:

$n\&GreaterEqual;\left[\frac{B}{b}\right]$

$m\&GreaterEqual;\left[\frac{L}{a}\right]$

Wherein, [] is for rounding symbol; A is for moving towards the center distance of the adjacent intumescent plain concrete of direction anchor pole (1) along side slope, unit is m; B is the center distance along the adjacent intumescent plain concrete of slope height direction anchor pole (1), and unit is m; B is the height of ground potential safety hazard district (2) along sloping high direction, and unit is m; To be ground potential safety hazard district (2) move towards the length of direction along side slope to L, and unit is m.

5. slope ground partial potential safety hazard according to claim 1 district intumescent supports the improvement method, and it is characterized in that: the method for expandable implant type plain concrete anchor pole (1) is as follows:

1) manually removes the surperficial surface dust in slope ground potential safety hazard district (2);

2), lay bolthole by anchor pole position, the spacing of design in the potential safety hazard district (2) of slope ground;

3) hole clear hole by designing requirement in the bolthole position;

4) preparation intumescent dilution concrete is in the injection hole, till the aperture has concrete slurry to overflow.

6. slope ground partial potential safety hazard according to claim 5 district intumescent supports the improvement method, and it is characterized in that: each bolthole is parallel along the hole direction of principal axis, and bolthole hole direction of principal axis is vertical with the soil table, hole depth 3～5m, aperture 0.15～0.20m; During intumescent dilution concrete injection hole, guarantee that the anchor pole slurry is full.

7. slope ground partial potential safety hazard according to claim 5 district intumescent supports the improvement method, it is characterized in that: the cement expansive material volume is 13～16% in the intumescent dilution concrete, and intumescent dilutes concrete expansion rate r=30～35%.

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