CN103899326B - Shield cutter difference installs the defining method of radius number of cutters - Google Patents

Abstract

The invention discloses a method for determining the number of cutters at different installation radii of a shield cutter head, which mainly includes five steps: dividing the cutter head into two areas, and several installation radii in the two areas respectively meet respective conditions; and then Calculate the advancing stress at each installation radius in area 1; determine the number n ₁ of tools at each installation radius in area 1; calculate the advancing stress σ _{2 at each installation radius in area 2} ; finally determine the The number of tools n ₂ at the installation radius. The present invention considers the stress characteristics of the cutters at different positions on the cutter head and the differences in the tunneling trajectories, determines the number of cutters at different installation radii of the shield cutter head, makes the service life of the cutters at different positions on the cutter head as close as possible, and effectively reduces replacement The number of knives is reduced, the production cost is reduced, and a scientific calculation basis is provided for the optimal design of the shield cutter head.

Description

Method for determining the number of cutters at different installation radii of the shield cutter head

technical field

The invention belongs to shield machine technology, and in particular relates to a method for determining the number of cutters at different installation radii of a shield cutterhead.

Background technique

Shield tunneling is a typical excavation equipment in underground engineering, and it has been widely used in various tunnel constructions. The cutterhead is located at the front of the equipment. In the shield machine, the cutter head and the cutter are like the "gum" and "teeth" of a person, and are the core components of the tunneling equipment. In principle, the current shield cutterheads have the same number of cutters installed with different cutterhead installation radii, that is, the number of cutters per ring with different radii is equal. However, since the loads on different areas of the cutter head are not uniform, and the cutter is at different positions on the cutter head, the cutting trajectories are not equal (generally, the closer to the edge of the cutter head, the greater the load, and of course the cutting trajectory of the tool is also different. relatively longer). If the same number of knives are set on different radii according to the current design method, the knives near the outer edge of the cutter head will be damaged first. If different numbers of cutterheads are set according to different radii on the cutterhead, what is the basis for its design? Since shield excavation is an underground closed construction, it is very difficult and expensive to open the warehouse and change the tool. Therefore, the present invention proposes a method for scientifically determining the number of cutters on a shield cutterhead, which can take into account the stress characteristics at different positions of the cutterhead and the differences in cutting trajectories of the cutters, so that the service life of the cutters at different positions on the cutterhead can be as close as possible to Reduce the number of tool changes and reduce production costs.

Contents of the invention

The purpose of the present invention is to propose a method for determining the number of cutters at different installation radii of the shield cutter head, so as to provide scientific and effective reference for shield equipment design.

The method for determining the number of cutters at different installation radii of the shield cutter head includes five steps:

(1) Due to the different force characteristics, the cutter head is first divided into two areas, and then the number of tools required for each installation radius in the two areas is determined separately: all tool installation radii satisfy The area is called area 1, where the tool installation radius satisfies The area is called area 2, where r ₁ and r ₂ represent the installation radii of the tools in area 1 and area 2 respectively, and R is the radius of the cutter head;

(2) Calculate the propulsion stress σ _{1 in area 1} :

${\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 54</span>}\mathrm{<span\; class="notranslate">\; E.</span>}\mathrm{<span\; class="notranslate">\; \&delta;</span>}}{\mathrm{<span\; class="notranslate">\; 13</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 14</span>}}{\mathrm{<span\; class="notranslate">\; 13</span>}}{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; ,</span>$

In the formula: E is the elastic modulus of the soil, μ is the Poisson’s ratio of the soil, δ is the excavation footage, and σ _s is the stress limit of the soil;

(3) Determine the number n _{1 of tools in area 1} :

${\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}\mathrm{<span\; class="notranslate">\; R</span>}}{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}$

In the formula: n _s is the number of tools at the edge of the cutter head;

(4) Calculate the propulsion stress σ _{2 in area 2} :

${\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; R</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}$

(5) Determine the number n _{2 of tools in area 2} :

${\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}\mathrm{<span\; class="notranslate">\; R</span>}}{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Thus, the specific quantity of cutters required on each installation radius in the two regions of the shield cutter head can be given.

There are several tool installation radii on each cutter head. The calculation formulas of the installation radii located in area 1 are the same, and the calculation formulas of the installation radii located in area 2 are the same. The installation radius in the formula is a variable. When calculating, first determine the installation radius value, and then substitute it into the corresponding zone 1 or zone 2 according to the condition area that the radius satisfies. Then use the corresponding calculation formula to determine.

The characteristics of the present invention and the positive effects produced are that, considering the force characteristics of the cutters at different positions on the cutter head and the differences in the tunneling trajectory, the number of cutters at different installation radii of the shield cutter head is determined, so that the number of cutters at different positions on the cutter head The service life is as close as possible, which effectively reduces the number of tool changes and production costs, and provides a scientific calculation basis for the optimal design of the shield cutter head.

detailed description

The method of the present invention will be further described below through specific examples. It should be noted that this example is descriptive, rather than limiting, and does not limit the protection scope of the present invention.

The method of determining the number of cutters at different installation radii of the shield cutter head is divided into the following five steps:

(1) Due to the different force characteristics, the cutter head is first divided into two areas, and then the number of tools required for each installation radius in the two areas is determined separately: all tool installation radii satisfy The area is called area 1, where the tool installation radius satisfies The area is called area 2, where r ₁ and r ₂ represent the installation radii of the tools in area 1 and area 2 respectively, and R is the radius of the cutter head;

(2) Calculate the propulsion stress σ _{1 in area 1} :

${\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 54</span>}\mathrm{<span\; class="notranslate">\; E.</span>}\mathrm{<span\; class="notranslate">\; \&delta;</span>}}{\mathrm{<span\; class="notranslate">\; 13</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 14</span>}}{\mathrm{<span\; class="notranslate">\; 13</span>}}{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; ,</span>$

In the formula: E is the elastic modulus of the soil, μ is the Poisson’s ratio of the soil, δ is the excavation footage, and σ _s is the stress limit of the soil;

(3) Determine the number n _{1 of tools in area 1} :

${\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}\mathrm{<span\; class="notranslate">\; R</span>}}{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}$

In the formula: n _s is the number of tools at the edge of the cutter head;

(4) Calculate the propulsion stress σ _{2 in area 2} :

${\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; R</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}$

(5) Determine the number n _{2 of tools in area 2} :

${\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}\mathrm{<span\; class="notranslate">\; R</span>}}{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Thus, the specific quantity of cutters required on each installation radius in the two regions of the shield cutter head can be given.

Example: The radius of the shield cutterhead used in this subway project is R=3.3m, and the number of edge cutters n _s =20; the geological parameters are taken from the engineering geological report, including soil elastic modulus E=5.6MPa, soil Poisson Ratio μ = 0.29, soil stress limit σ _s = 46kPa; preset excavation footage δ = 0.03m/rev.

Taking the determination and calculation of the number of tools at the two installation radii on the cutterhead as an example (the two installation radii are respectively r ₁ =1.0m and r ₂ =2.4m), specific steps are given, and the other installation radii The number of tool arrangements can be determined in the same way.

(1) First determine which area the two installation radii r ₁ =1.0m and r ₂ =2.4m are located in: because Therefore r ₁ =1.0m is located in region 1 and r ₂ =2.4m is located in region 2;

(2) Calculate the thrust stress σ ₁ at the installation radius r ₁ =1.0m (in area 1):

Depend on ${\mathrm{\&sigma;}}_1=\frac{54\mathrm{E.}\mathrm{\&delta;}}{13\mathrm{\&pi;}R(1-{\mathrm{\&mu;}}^2)}-\frac{14}{13}{\mathrm{\&sigma;}}_{\mathrm{the\; s}},,$ Get σ ₁ =24.0kPa

(3) Determine the number n ₁ of tools at the installation radius r ₁ =1.0m (located in area 1):

Depend on ${\mathrm{no}}_1=\frac{{\mathrm{no}}_{\mathrm{the\; s}}{r}_1}{{\mathrm{\&sigma;}}_{\mathrm{the\; s}}R}{\mathrm{\&sigma;}}_1,$ get n ₁ =3

(4) Calculate the thrust stress σ ₂ at the installation radius r ₂ =2.4m (located in area 2):

Depend on ${\mathrm{\&sigma;}}_2=\frac{3}{2R}(r_2-R)({\mathrm{\&sigma;}}_{\mathrm{the\; s}}-{\mathrm{\&sigma;}}_1)+{\mathrm{\&sigma;}}_{\mathrm{the\; s}},$ Get σ ₂ =37.0kPa

(5) Determine the number n ₂ of tools at the installation radius r ₂ =2.4m (in area 2):

Depend on ${\mathrm{no}}_2=\frac{{\mathrm{no}}_{\mathrm{the\; s}}{r}_2}{{\mathrm{\&sigma;}}_{\mathrm{the\; s}}R}{\mathrm{\&sigma;}}_2,$ get n ₂ =12

So far, the number of cutters installed on the cutter head at the radius r ₁ =1.0m and r ₂ =2.4m has been determined.

The number of knives at the other installation radii on the cutter head can be determined in the same way. This gives the number of cutters at different installation radii on the entire shield cutter head.

Claims (1)

1. shield cutter difference installs the defining method of radius number of cutters, it is characterized in that described method is divided into following five steps:

(1) according to stress characteristic, first cutterhead is divided into two regions, then determines that in these two regions, each installs number of cutters required on radius respectively: if Cutting tool installation manner radius meets region put region 1 under, if Cutting tool installation manner radius meets region put region 2 under, wherein r ₁and r ₂represent each bar of cutter in region 1 and region 2 respectively and install radius, R is cutter radius;

(2) the propelling stress σ in zoning 1 ₁:

${\mathrm{\&sigma;}}_1=\frac{54E\mathrm{\&delta;}}{13\mathrm{\&pi;}R(1-{\mathrm{\&mu;}}^2)}-\frac{14}{13}{\mathrm{\&sigma;}}_s,$

In formula: E is elastic modulus of soil body, μ is soil's Poisson ratio, and δ is digging footage, σ _sfor the limiting range of stress of the soil body;

(3) the number of cutters n in region 1 is determined ₁:

$n_1=\frac{n_s{r}_1}{{\mathrm{\&sigma;}}_{s}R}{\mathrm{\&sigma;}}_1$

In formula: n _sfor the number of cutters of cutterhead edge;

(4) the propelling stress σ in zoning 2 ₂:

${\mathrm{\&sigma;}}_2=\frac{3}{2R}(r_2-R)({\mathrm{\&sigma;}}_s-{\mathrm{\&sigma;}}_1)+{\mathrm{\&sigma;}}_s$

(5) the number of cutters n in region 2 is determined ₂:

$n_2=\frac{n_s{r}_2}{{\mathrm{\&sigma;}}_{s}R}{\mathrm{\&sigma;}}_2$

The concrete quantity that each bar in shield cutter two regions installs required cutter on radius can be provided thus.