阅读说明：本技术 一种适用于软硬结构面相间岩体的***方法 (Blasting method suitable for soft and hard structural plane interphase rock mass ) 是由 武仁杰 李海波 李晓锋 刘黎旺 于 2020-09-02 设计创作，主要内容包括：本发明公开了一种适用于软硬结构面相间岩体的爆破方法,包含如下步骤：获取将要爆破的软硬结构面相间岩体各结构面及裂隙发育情况；测量各结构面岩石强度、弹性模量；对各结构面岩石强度、弹性模量及裂隙发育情况进行打分,得到各结构面的岩体参数分值；根据岩体参数分值,判定需要水泥灌浆改善的软弱结构面；根据需要进行水泥灌浆改善的软弱结构面的岩体参数分值,确定需灌注的水泥浆类型；利用水泥灌浆装置对软弱结构面处进行水泥灌浆加固；对经过水泥灌浆加固后的爆破孔进行装药爆破。本发明的优点是：能将泥浆准确注入软弱结构面处,从而增加软弱结构面的强度,减少不同岩体之间的岩性差异化,能有效避免软弱结构面处的炸药冲击波泄露问题。(The invention discloses a blasting method suitable for a soft and hard structural plane interphase rock mass, which comprises the following steps: acquiring the development conditions of all structural surfaces and cracks of a soft and hard structural surface interphase rock mass to be blasted; measuring the rock strength and the elastic modulus of each structural surface; scoring the rock strength, the elastic modulus and the fracture development condition of each structural surface to obtain rock mass parameter values of each structural surface; judging a weak structural plane needing to be improved by cement grouting according to the value of the rock mass parameter; determining the type of cement paste to be poured according to the rock mass parameter value of the soft structural surface needing to be improved by cement grouting; carrying out cement grouting reinforcement on the soft structure surface by using a cement grouting device; and (5) carrying out charging blasting on the blast hole reinforced by the cement grouting. The invention has the advantages that: the slurry can be accurately injected into the weak structural plane, so that the strength of the weak structural plane is increased, the lithological differentiation between different rock masses is reduced, and the problem of explosive shock wave leakage at the weak structural plane can be effectively avoided.)

1. A blasting method suitable for a soft and hard structural plane interphase rock mass is characterized by comprising the following steps: comprises the following steps:

s1, drilling blasting holes at corresponding parts of the interphase rock mass of the soft and hard structural surfaces to be blasted;

s2, exploring the geological structure in the blast hole to obtain the development conditions of each structural surface and crack of the soft and hard structural surface interphase rock mass to be blasted;

s3, measuring the rock strength and the elastic modulus of each structural surface of the soft and hard structural surface interphase rock mass to be blasted, and knowing the crack development condition of each structural surface of the soft and hard structural surface interphase rock mass to be blasted by means of a Monte Carlo method;

s4, scoring the rock strength, the elastic modulus and the crack development condition of each structural surface of the hard and soft structural surface interphase rock mass to be blasted to obtain rock mass parameter values corresponding to each structural surface of the hard and soft structural surface interphase rock mass to be blasted;

the rock mass parameter score is composed of three contents of a score corresponding to the rock mass strength of the structural plane, a score corresponding to the elastic modulus and a score corresponding to the fracture development condition;

s5, according to the rock mass parameter values obtained in the step S4, determining a weak structural plane needing to be improved by cement grouting in the rock mass with the interphase hard and soft structural planes to be blasted;

s6, determining the type of cement mortar to be poured into the weak structural surface needing to be improved by cement grouting according to the rock mass parameter value condition corresponding to the weak structural surface needing to be improved by cement grouting determined in the step S5;

s7, preparing corresponding cement paste according to the type of the cement paste determined in the step S6, and then carrying out cement grouting reinforcement treatment on the weak structural surface needing cement grouting improvement in the interphase rock mass of the hard and soft structural surface to be blasted by using a cement grouting device;

and S8, carrying out charging blasting on the blast hole reinforced by the cement grouting.

2. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 1, characterized by comprising the following steps: step S4, scoring the rock strength, the elastic modulus and the fracture development condition of each structural surface of the hard and soft structural surface interphase rock mass to be blasted to obtain rock mass parameter values corresponding to each structural surface of the hard and soft structural surface interphase rock mass to be blasted, and the concrete steps are as follows:

s41, making a rock parameter grading table, and marking out corresponding values under different rock strength, different elastic modulus and different fracture development conditions;

in the rock mass parameter scoring table, for the rock mass strength, the scores corresponding to different rock mass strength grades are as follows:

when the strength of the rock mass is more than or equal to 80MPa, the corresponding score is 1;

when the strength of the rock mass is less than 80MPa and more than or equal to 50MPa, the corresponding score is 2;

when the strength of the rock mass is less than 50MPa and more than or equal to 30MPa, the corresponding score is 3;

when the strength of the rock mass is less than 30MPa, the corresponding score is 5

In the rock mass parameter scoring table, for the elastic modulus of the rock mass, the scores corresponding to different rock mass elastic modulus grades are as follows:

when the elastic modulus of the rock mass is more than or equal to 30GPa, the corresponding score is 1;

when the elastic modulus of the rock mass is less than 30GPa and more than or equal to 20GPa, the corresponding score is 2;

when the elastic modulus of the rock mass is less than 20GPa and more than or equal to 10GPa, the corresponding score is 3;

when the elastic modulus of the rock mass is less than 10GPa, the corresponding score is 5;

in the rock mass parameter scoring table, for the rock mass fracture development conditions, the scores corresponding to different rock mass fracture development conditions are as follows:

when no crack exists in the rock mass, the corresponding score is 1 score;

when the rock mass has micro cracks, the corresponding score is 2 points;

when 1 main crack is in the rock mass, the corresponding score is 3;

when the number of the main cracks in the rock mass is not less than 2, the corresponding score is 5;

wherein, the micro-cracks represent cracks with the width less than 2cm, and the main cracks represent cracks with the width more than or equal to 2 cm;

s42, scoring the strength of each structural face rock of the soft and hard structural face interphase rock mass to be blasted by referring to the rock mass parameter scoring table formulated in the step S41, and acquiring a score value corresponding to the strength of each structural face rock of the soft and hard structural face interphase rock mass to be blasted;

s43, scoring the elastic modulus of each structural face rock of the hard and soft structural face interphase rock mass to be blasted by referring to the rock mass parameter scoring table formulated in the step S41, and acquiring a score value corresponding to the elastic modulus of each structural face rock of the hard and soft structural face interphase rock mass to be blasted;

s44, scoring the fracture development condition of each structural surface rock of the soft and hard structural surface interphase rock mass to be blasted according to the rock mass parameter scoring table formulated in the step S41, and acquiring a score value corresponding to the fracture development condition of each structural surface rock of the soft and hard structural surface interphase rock mass to be blasted;

s45, summing the rock strength, the elastic modulus and the fracture development condition fractions corresponding to the structural surfaces obtained in the steps S42 to S44 to obtain rock mass parameter values corresponding to each structural surface in the hard-soft structural surface interphase rock mass to be blasted;

the rock mass parameter value corresponding to each structural surface in the hard and soft structural surface interphase rock mass to be blasted is specifically obtained by the following calculation (1):

F₁＝S_P+S_E+S_C(1)

in formula (1): f₁Representing a rock mass parameter value corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted; s_PThe method comprises the steps of (1) representing a scoring value of rock mass strength corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted; s_EThe method comprises the steps of (1) representing a scoring value of the elastic modulus of a rock body corresponding to a certain structural plane in a hard-soft structural plane interphase rock body to be blasted; s_CAnd the score of the rock mass fracture development condition corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted is shown.

3. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 2, characterized by comprising the following steps: step S5, according to the rock mass parameter value, the concrete method for judging the weak structural plane needing to be improved by cement grouting in the hard and soft structural plane interphase rock mass to be blasted comprises the following steps:

finding out the structural plane with the rock mass parameter value being more than or equal to 7 according to the rock mass parameter value corresponding to each structural plane in the hard-hard structural plane interphase rock mass to be blasted obtained in the step S4, wherein the structural plane with the rock mass parameter value being more than or equal to 7 is the soft structural plane which needs to be improved by grouting;

when the parameter value of the rock mass is equal to 7, the condition that cement slurry needs to be poured is just met for the rock mass with the interphase hard and soft structural planes to be blasted.

4. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 3, characterized by comprising the following steps: step S6, according to the determined rock mass parameter value condition corresponding to the weak structural plane needing grouting improvement, the concrete steps of determining the type of cement mortar to be poured into the weak structural plane needing grouting improvement are as follows:

s61, subtracting 4 from the rock mass parameter value corresponding to the judged weak structural plane needing grouting improvement to obtain a corresponding cement paste improvement capacity value;

s62, making a cement paste improvement capability grading table, and marking out corresponding improvement capability scores under different water pump strengths and different additives;

in the cement paste improvement capability scoring table, for the cement strength, the improvement capability scores corresponding to different cement strength grades are specifically as follows:

when the strength of the cement is more than or equal to 50MPa, the corresponding improving capability score is 5;

when the strength of the cement is less than 50MPa and more than or equal to 35MPa, the corresponding improving capability score is 3;

when the strength of the cement is less than 35MPa and more than or equal to 20MPa, the corresponding improving capability score is 2;

when the strength of the cement is less than 20MPa, the corresponding improving capability score is 1 score;

in the cement slurry improvement capability score table, for the additives, the improvement capability scores corresponding to different additives are specifically as follows:

when the additive is fiber, the early strength agent and the expanding agent, the corresponding improving capability score is 5;

when the additive is an expanding agent and an early strength agent, the corresponding improving capability score is 3;

when the additive is an early strength agent, the corresponding improving capability score is 2 scores;

in the absence of additive, the corresponding improvement score is 1 score;

and S63, referring to the cement paste improvement capability score table formulated in the step S62, selecting the cement paste which can meet the cement paste improvement capability score condition obtained in the step S61 from the table, wherein the cement paste is the type of the cement paste which needs to be poured on the weak structural plane needing to be subjected to cement grouting improvement in the rock mass with the interphase hard and soft structural planes to be blasted.

5. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 1, characterized by comprising the following steps: the cement grouting device in the step S7 comprises a grouting rod (1) and at least two expansion rubber sleeves (2) which are sleeved on the grouting rod (1) in a sliding manner; a grouting channel (3) is axially formed in the middle of the grouting rod (1), a plurality of grouting ports (4) are axially formed in the rod wall of the grouting rod (1), and each grouting port (4) is communicated with the grouting channel (3) formed in the middle of the grouting rod (1); when the cement grouting device is used, each expansion rubber sleeve (2) is fixed on the outer rod wall of each grouting rod (1) through a positioning bolt (5), and the distance between every two adjacent expansion rubber sleeves (2) is larger than or equal to the thickness of a weak structural surface to be improved by cement grouting in a rock body with interphase hard and soft structural surfaces to be blasted.

6. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 5, characterized in that: the grouting rod (1) is formed by sequentially splicing a plurality of sections of grouting cylinders (1.1) through a plurality of spiral rings (6).

7. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 6, characterized in that: a grouting hole (1.1a) is formed in the middle of each section of grouting cylinder (1.1) along the axial direction; when the grouting device is used, grouting holes (1.1) formed in the middle of each section of grouting cylinder (1.1) forming the grouting rod (1) are communicated with each other, and jointly form a grouting channel (3) formed in the middle of the grouting rod (1) along the axial direction.

8. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 7, characterized in that: a plurality of grouting openings (4) are axially formed in the wall of each section of grouting cylinder (1.1), and each grouting opening (4) in each section of grouting cylinder (1.1) is communicated with a grouting hole (1.1a) formed in the middle of the grouting cylinder.

9. The blasting method suitable for the hard and soft structural face interphase rock mass according to claim 8, characterized in that: before the cement grouting device is used, each grouting opening (4) on the grouting rod (1) is sealed or unsealed; when the grouting rod is used, except for the fact that the grouting openings (4) at the positions of the grouting rod (1) sleeved with the expansion rubber sleeves (2) are not sealed, the grouting openings (4) at the other positions are sealed.

10. The method for blasting the interphase rock mass with the soft and hard structural surfaces as claimed in claim 9, wherein the method comprises the following steps: before the cement grouting device is used, each grouting opening (4) on the grouting rod (1) is sealed by a sealant (7) or a detachable grouting valve (8); when the grouting rod is used, except that the grouting opening (4) at the part of the grouting rod (1) which is sleeved with the expansion rubber sleeve (2) is not sealed, the grouting openings (4) at other parts are all sealed by the sealant (7).

Technical Field

The invention relates to the technical field of rock-soil blasting, in particular to a blasting method suitable for soft and hard structural surface interphase rock mass.

Background

In the process of excavating building rock masses such as surface mining, underground tunnel drilling and blasting tunneling, water conservancy and hydropower and the like, more and more geological conditions with complex structures are encountered, such as: the soft and hard structural surface rock mass is staggered, cracks develop, explosive energy in holes leaks, and the utilization rate is insufficient, so that the phenomena of large blocks, roots and flying stones are caused, therefore, stricter safety measures and secondary blasting are often needed, and the problems of slow progress and high cost are caused. Wherein, the soft and hard structural plane rock mass is staggered, the crack development often coexists, in order to solve the above-mentioned problem, the following processing method is proposed in the industry:

(1) and (4) optimizing the explosive charging structure, namely, after the development conditions of the structural surface and the fracture in the rock body are detected by using pinhole camera shooting, placing the explosive in a sectional differentiation mode. According to the invention CN106679522A, after the energy leakage area in the blast hole is analyzed, the uncoupled expanded ammonium nitrate explosive column is adopted in the leakage layer, and the emulsion explosive is adopted above the leakage layer for coupled charging, so that the further utilization of the explosive energy is realized. However, the method is only suitable for the condition that one main leakage layer exists, when a plurality of leakage layers of the weak structure surface exist, the upper part and the lower part of the leakage layers are not clear any more, and the charging mode is also complicated.

(2) Under the condition of crack development, after explosives are placed at the top and the bottom, full-hole pouring concrete is used for filling cracks, and then blasting is carried out. However, the explosive is not placed in a hard structural layer, so that the blasting effect is not ideal.

(3) The use of auxiliary charge holes or an optimized detonation network results in a better blasting effect. The method can improve the blasting condition in the homogeneous and complete rock mass, but can not solve the problems of energy leakage, uneven damage and the like caused by the existence of a soft structural layer, and can not radically solve the problems of staggered and alternate rock mass and crack development conditions of a soft and hard structural surface.

Disclosure of Invention

The invention aims to provide a blasting method specially suitable for interphase rock masses with soft and hard structural planes, which is used for solving the problems in the background technology.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a blasting method suitable for a soft and hard structural plane interphase rock mass is characterized by comprising the following steps: comprises the following steps:

s1, drilling blasting holes at corresponding parts of the interphase rock mass of the soft and hard structural surfaces to be blasted;

s2, exploring the geological structure in the blast hole to obtain the development conditions of each structural surface and crack of the soft and hard structural surface interphase rock mass to be blasted;

s3, measuring the rock strength and the elastic modulus of each structural surface of the soft and hard structural surface interphase rock mass to be blasted, and knowing the crack development condition of each structural surface of the soft and hard structural surface interphase rock mass to be blasted by means of a Monte Carlo method;

s4, scoring the rock strength, the elastic modulus and the crack development condition of each structural surface of the hard and soft structural surface interphase rock mass to be blasted to obtain rock mass parameter values corresponding to each structural surface of the hard and soft structural surface interphase rock mass to be blasted;

the rock mass parameter score is composed of three contents of a score corresponding to the rock mass strength of the structural plane, a score corresponding to the elastic modulus and a score corresponding to the fracture development condition;

s5, according to the rock mass parameter values obtained in the step S4, determining a weak structural plane needing to be improved by cement grouting in the rock mass with the interphase hard and soft structural planes to be blasted;

s6, determining the type of cement mortar to be poured into the weak structural surface needing grouting improvement according to the rock mass parameter value condition corresponding to the weak structural surface needing grouting improvement determined in the step S5;

s7, preparing corresponding cement tank slurry according to the type of the cement mortar determined in the step S6, and then carrying out cement grouting reinforcement treatment on a weak structural surface needing cement grouting improvement in the interphase rock mass of the soft and hard structural surface to be blasted by using a cement grouting device;

and S8, carrying out charging blasting on the blast hole reinforced by the cement grouting.

In the above technical scheme, step S4, scoring the rock strength, elastic modulus and fracture development condition of each structural surface of the hard-hard structural surface interphase rock mass to be blasted to obtain rock mass parameter scores corresponding to each structural surface of the hard-hard structural surface interphase rock mass to be blasted specifically includes the following steps:

s41, making a rock parameter grading table, and marking out corresponding values under different rock strength, different elastic modulus and different fracture development conditions;

in the rock mass parameter scoring table, for the rock mass strength, the scores corresponding to different rock mass strength grades are as follows:

when the strength of the rock mass is more than or equal to 80MPa, the corresponding score is 1;

when the strength of the rock mass is less than 80MPa and more than or equal to 50MPa, the corresponding score is 2;

when the strength of the rock mass is less than 50MPa and more than or equal to 30MPa, the corresponding score is 3;

when the strength of the rock mass is less than 30MPa, the corresponding score is 5

In the rock mass parameter scoring table, for the elastic modulus of the rock mass, the scores corresponding to different rock mass elastic modulus grades are as follows:

when the elastic modulus of the rock mass is more than or equal to 30GPa, the corresponding score is 1;

when the elastic modulus of the rock mass is less than 30GPa and more than or equal to 20GPa, the corresponding score is 2;

when the elastic modulus of the rock mass is less than 20GPa and more than or equal to 10GPa, the corresponding score is 3;

when the elastic modulus of the rock mass is less than 10GPa, the corresponding score is 5;

in the rock mass parameter scoring table, for the rock mass fracture development conditions, the scores corresponding to different rock mass fracture development conditions are as follows:

when no crack exists in the rock mass, the corresponding score is 1 score;

when the rock mass has micro cracks, the corresponding score is 2 points;

when 1 main crack is in the rock mass, the corresponding score is 3;

when the number of the main cracks in the rock mass is not less than 2, the corresponding score is 5;

wherein, the micro-cracks represent cracks with the width less than 2cm, and the main cracks represent cracks with the width more than or equal to 2 cm;

s42, scoring the strength of each structural face rock of the soft and hard structural face interphase rock mass to be blasted by referring to the rock mass parameter scoring table formulated in the step S41, and acquiring a score value corresponding to the strength of each structural face rock of the soft and hard structural face interphase rock mass to be blasted;

s43, scoring the elastic modulus of each structural face rock of the hard and soft structural face interphase rock mass to be blasted by referring to the rock mass parameter scoring table formulated in the step S41, and acquiring a score value corresponding to the elastic modulus of each structural face rock of the hard and soft structural face interphase rock mass to be blasted;

s44, scoring the fracture development condition of each structural surface rock of the soft and hard structural surface interphase rock mass to be blasted according to the rock mass parameter scoring table formulated in the step S41, and acquiring a score value corresponding to the fracture development condition of each structural surface rock of the soft and hard structural surface interphase rock mass to be blasted;

s45, summing the rock strength, the elastic modulus and the fracture development condition fractions corresponding to the structural surfaces obtained in the steps S42 to S44 to obtain rock mass parameter values corresponding to each structural surface in the hard-soft structural surface interphase rock mass to be blasted;

the rock mass parameter value corresponding to each structural surface in the hard and soft structural surface interphase rock mass to be blasted is specifically obtained by the following calculation (1):

F₁＝S_P+S_E+S_C(1)

in formula (1): f₁Representing a rock mass parameter value corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted; s_PThe method comprises the steps of (1) representing a scoring value of rock mass strength corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted; s_EThe method comprises the steps of (1) representing a scoring value of the elastic modulus of a rock body corresponding to a certain structural plane in a hard-soft structural plane interphase rock body to be blasted; s_CAnd the score of the rock mass fracture development condition corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted is shown.

In the above technical solution, the specific method for determining the weak structural plane to be improved by cement grouting in the hard and soft structural plane interphase rock mass to be blasted according to the rock mass parameter score in step S5 is as follows:

finding out the structural plane with the rock mass parameter value being more than or equal to 7 according to the rock mass parameter value corresponding to each structural plane in the hard-hard structural plane interphase rock mass to be blasted obtained in the step S4, wherein the structural plane with the rock mass parameter value being more than or equal to 7 is the soft structural plane which needs to be improved by grouting;

when the parameter value of the rock mass is equal to 7, the condition that cement slurry needs to be poured is just met for the rock mass with the interphase hard and soft structural planes to be blasted.

In the above technical solution, the step S6 of determining the type of cement mortar to be poured into the weak structural surface to be improved by cement grouting according to the determined rock mass parameter value condition corresponding to the weak structural surface to be improved by grouting includes the following specific steps:

s61, subtracting 4 from the rock mass parameter value corresponding to the judged weak structural plane needing grouting improvement to obtain a corresponding cement paste improvement capacity value;

s62, making a cement paste improvement capability grading table, and marking out corresponding improvement capability scores under different water pump strengths and different additives;

in the cement paste improvement capability scoring table, for the cement strength, the improvement capability scores corresponding to different cement strength grades are specifically as follows:

when the strength of the cement is more than or equal to 50MPa, the corresponding improving capability score is 5;

when the strength of the cement is less than 50MPa and more than or equal to 35MPa, the corresponding improving capability score is 3;

when the strength of the cement is less than 35MPa and more than or equal to 20MPa, the corresponding improving capability score is 2;

when the strength of the cement is less than 20MPa, the corresponding improving capability score is 1 score;

in the cement slurry improvement capability score table, for the additives, the improvement capability scores corresponding to different additives are specifically as follows:

when the additive is fiber, the early strength agent and the expanding agent, the corresponding improving capability score is 5;

when the additive is an expanding agent and an early strength agent, the corresponding improving capability score is 3;

when the additive is an early strength agent, the corresponding improving capability score is 2 scores;

in the absence of additive, the corresponding improvement score is 1 score;

and S63, referring to the cement paste improvement capability score table formulated in the step S62, selecting the cement paste which can meet the cement paste improvement capability score condition obtained in the step S61 from the table, wherein the cement paste is the type of the cement paste which needs to be poured on the weak structural plane needing to be subjected to cement grouting improvement in the rock mass with the interphase hard and soft structural planes to be blasted.

In the above technical solution, the cement grouting device in step S7 includes a grouting rod and at least two expansion rubber sleeves slidably sleeved on the grouting rod; the grouting rod) is provided with a grouting channel along the axial direction, the rod wall of the grouting rod is provided with a plurality of grouting ports along the axial direction, and each grouting port is communicated with the grouting channel arranged in the middle of the grouting rod; when the cement grouting device is used, each expansion rubber sleeve is fixed on the outer rod wall of the grouting rod through a positioning bolt, and the distance between every two adjacent expansion rubber sleeves is larger than or equal to the thickness of a weak structural surface needing to be improved by cement grouting in a soft and hard structural surface interphase rock mass to be blasted.

In the technical scheme, the grouting rod is formed by sequentially splicing a plurality of grouting barrels through a plurality of spiral rings.

In the technical scheme, a grouting hole is formed in the middle of each section of the grouting barrel along the axial direction; when the grouting device is used, grouting holes formed in the middle of each section of grouting cylinder forming the grouting rod are mutually communicated, and form a grouting channel formed in the middle of the grouting rod along the axial direction.

In the technical scheme, a plurality of grouting ports are axially formed in the wall of each section of grouting cylinder, and each grouting port in each section of grouting cylinder is communicated with a grouting hole formed in the middle of the grouting cylinder.

In the technical scheme, before the cement grouting device is used, each grouting opening on the grouting rod is sealed or unsealed; when the grouting rod is used, the grouting openings of the grouting rod are sealed except the grouting opening at the position where the expansion rubber sleeve is sleeved.

In the technical scheme, before the cement grouting device is used, each grouting opening on the grouting rod is sealed by adopting a sealant or a detachable grouting valve; when the grouting device is used, except that the grouting opening at the position where the expansion rubber sleeve is sleeved on the grouting rod is not sealed, the grouting openings at other positions are sealed by adopting a sealant.

Compared with the prior art, the invention has the advantages that:

(1) an evaluation system for rock mass parameter hole blasting and cement slurry improvement is constructed, and the evaluation system are combined, so that the method can be applied to the interaction condition of the soft and hard structural surfaces, and can be applied to the evaluation of other rocks containing cracks.

(2) The slurry can be accurately injected into the weak structural surface, the hole wall environment is greatly improved, and gaps existing in the hole wall environment are filled, so that the strength of the weak structural surface is increased, and the lithological differentiation is reduced.

(3) The explosive can be loaded at any position, can couple the explosive to hard rock department on this basis to reach crushing effect, in grout position department, can utilize the big characteristics of cement wall ductility that mud formed not coupling loading, increase the duration of blasting, thereby improve the blasting.

(4) The cement crack pouring device is easy to operate, can be changed according to different geological conditions, and can be recycled;

(5) the used filling cement slurry is convenient and easy to obtain, the cost is low, and the total cost of blasting can be effectively reduced;

(6) in the grouting process, high-pressure impact is not needed to break the rock mass, additional pressurizing equipment is not needed, and supporting facilities are simple.

Drawings

FIG. 1 is a process flow of the present invention;

FIG. 2 is a schematic diagram of the geological condition of an alternate rock mass of a soft and hard structural plane;

FIG. 3 is a schematic diagram of the geological condition of another embodiment of the hard and soft structural surface interphase rock mass;

FIG. 4 is a schematic diagram of an embodiment of a cement crack pouring device adopted on the basis of the embodiment of the rock mass with the hard and soft structural surfaces arranged alternately in the FIG. 2;

FIG. 5 is a schematic cross-sectional view of the embodiment of the grout joint sealing device of FIG. 4 prior to grouting;

FIG. 6 is a schematic cross-sectional view of the embodiment of the grout joint filling apparatus of FIG. 4 in grouting use;

FIG. 7 is an enlarged view taken at A in FIG. 5;

FIG. 8 is an enlarged view of FIG. 6 at B;

FIG. 9 is a schematic diagram of an embodiment of a cement crack pouring device adopted on the basis of the embodiment of the rock mass with the hard and soft structural surfaces arranged alternately in FIG. 3;

FIG. 10 is a schematic cross-sectional view of the embodiment of the grout joint filling apparatus of FIG. 9 prior to grouting;

FIG. 11 is a schematic cross-sectional view of the embodiment of the grout joint filling apparatus of FIG. 9 in grouting use;

FIG. 12 is an enlarged view at C of FIG. 10;

FIG. 13 is an enlarged view of FIG. 11 at D;

description of reference numerals: 1. a grouting rod; 1.1, a grouting cylinder; 1.2, spiro ring; 2. expanding the rubber sleeve; 3. positioning the bolt; 4. grouting a channel; 5. a grouting port; 6. sealing glue; 7. grouting valve.

Detailed Description

In order to make the technical means, the creation features, the achievement purposes and the effects of the invention easy to understand, the following description further explains how the invention is implemented by combining the attached drawings and the detailed implementation modes.

Referring to fig. 1, the invention provides a blasting method suitable for a hard-soft structural plane interphase rock mass, which specifically includes the following steps:

s1, drilling blasting holes in corresponding parts of the interphase rock mass of the soft and hard structural planes to be blasted by using drilling equipment;

s2, exploring the geological structure in the blast hole by using a hole exploring imaging device to obtain each structural surface and crack development condition of the interphase rock mass of the soft and hard structural surfaces to be blasted;

s3, measuring the rock strength and the elastic modulus of each structural surface of the soft and hard structural surface interphase rock mass to be blasted by using a rock mechanics test system, and knowing the crack development condition of each structural surface of the soft and hard structural surface interphase rock mass to be blasted by using a Monte Carlo method;

s4, scoring the rock strength, the elastic modulus and the crack development condition of each structural surface of the hard and soft structural surface interphase rock mass to be blasted to obtain rock mass parameter values corresponding to each structural surface of the hard and soft structural surface interphase rock mass to be blasted;

the rock mass parameter score is composed of three contents of a score corresponding to the rock mass strength of the structural plane, a score corresponding to the elastic modulus and a score corresponding to the fracture development condition;

s5, according to the rock mass parameter values obtained in the step S4, determining a weak structural plane needing to be improved by cement grouting in the rock mass with the interphase hard and soft structural planes to be blasted;

s6, determining the type of cement mortar to be poured into the weak structural surface needing grouting improvement according to the rock mass parameter value condition corresponding to the weak structural surface needing grouting improvement determined in the step S5;

s7, preparing corresponding cement tank slurry according to the type of the cement mortar determined in the step S6, and then carrying out cement grouting reinforcement treatment on a weak structural surface needing cement grouting improvement in the interphase rock mass of the soft and hard structural surface to be blasted by using a cement grouting device;

and S8, carrying out charging blasting on the blast hole reinforced by the cement grouting.

Specifically, in step S4, the method for scoring the rock strength, the elastic modulus and the fracture development condition of each structural surface of the hard-hard structural surface interphase rock mass to be blasted to obtain the rock mass parameter score corresponding to each structural surface of the hard-hard structural surface interphase rock mass to be blasted specifically includes the following steps:

s41, making a rock parameter scoring table, and scoring out the corresponding scores of different rock strengths, different elastic moduli and different fracture development conditions, as shown in the following table 1:

TABLE 1 grading table for rock parameters

In the above table 1, for the rock strength, the scores corresponding to different rock strength grades are as follows:

when the strength of the rock mass is more than or equal to 80MPa, the corresponding score is 1;

when the strength of the rock mass is less than 80MPa and more than or equal to 50MPa, the corresponding score is 2;

when the strength of the rock mass is less than 50MPa and more than or equal to 30MPa, the corresponding score is 3;

when the strength of the rock mass is less than 30MPa, the corresponding score is 5

In the rock mass parameter scoring table 1, for the rock mass elastic modulus, the scores corresponding to different rock mass elastic modulus grades are specifically as follows:

when the elastic modulus of the rock mass is more than or equal to 30GPa, the corresponding score is 1;

when the elastic modulus of the rock mass is less than 30GPa and more than or equal to 20GPa, the corresponding score is 2;

when the elastic modulus of the rock mass is less than 20GPa and more than or equal to 10GPa, the corresponding score is 3;

when the elastic modulus of the rock mass is less than 10GPa, the corresponding score is 5;

in the above table 1, for the rock fracture development conditions, the corresponding scores for different rock fracture development conditions are as follows:

when no crack exists in the rock mass, the corresponding score is 1 score;

when the rock mass has micro cracks, the corresponding score is 2 points;

when 1 main crack is in the rock mass, the corresponding score is 3;

when the number of the main cracks in the rock mass is not less than 2, the corresponding score is 5;

wherein, the micro-cracks represent cracks with the width less than 2cm, and the main cracks represent cracks with the width more than or equal to 2 cm;

s42, scoring the strength of each structural face rock of the hard and soft structural face interphase rock mass to be blasted by referring to the rock mass parameter scoring table (namely the table 1 above) formulated in the step S41, and acquiring a score value corresponding to the strength of each structural face rock of the hard and soft structural face interphase rock mass to be blasted;

s43, scoring the elastic modulus of each structural face rock of the hard and soft structural face interphase rock mass to be blasted by referring to the rock mass parameter scoring table (namely the table 1 above) formulated in the step S41, and acquiring a score value corresponding to the elastic modulus of each structural face rock of the hard and soft structural face interphase rock mass to be blasted;

s44, scoring the fracture development condition of each structural surface rock of the hard and soft structural surface interphase rock mass to be blasted by referring to the rock mass parameter scoring table (namely the table 1 above) formulated in the step S41, and acquiring a score value corresponding to the fracture development condition of each structural surface rock of the hard and soft structural surface interphase rock mass to be blasted;

s45, summing the rock strength, the elastic modulus and the fracture development condition fractions corresponding to the structural surfaces obtained in the steps S42 to S44 to obtain rock mass parameter values corresponding to each structural surface in the hard-soft structural surface interphase rock mass to be blasted;

the rock mass parameter value corresponding to each structural surface in the hard and soft structural surface interphase rock mass to be blasted is specifically obtained by the following calculation (1):

F₁＝S_P+S_E+S_C(1)

in formula (1): f₁Representing a rock mass parameter value corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted; s_PThe method comprises the steps of (1) representing a scoring value of rock mass strength corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted; s_EThe method comprises the steps of (1) representing a scoring value of the elastic modulus of a rock body corresponding to a certain structural plane in a hard-soft structural plane interphase rock body to be blasted; s_CAnd the score of the rock mass fracture development condition corresponding to a certain structural plane in the hard and soft structural plane interphase rock mass to be blasted is shown.

In the above table 1, for the strength of the rock mass, the corresponding fraction is 1 point when the strength is greater than 80MPa, which represents a hard structural surface; when the pressure is less than 30MPa, the corresponding fraction is 5 points, which represents a weak structural plane; for the elastic modulus of the rock mass, the deformation is difficult when the elastic modulus is more than 30GPa, and the corresponding fraction is 1 point; when the deformation is less than 10GPa, the rock mass deforms less under the impact force, possibly belongs to a weak filling layer, and the corresponding fraction is 5 points; for the development of cracks, when no cracks or micro cracks (namely the width is less than 2cm) exist, the energy of the explosive is fully utilized, and the score of the explosive is smaller and is 1 or 2; after a main gap with the width larger than 2cm appears, a leakage layer can be formed, the blasting effect can be obviously interfered, and the score at the moment is centered and is 3 scores; when more than one main fracture exists, the traditional method for avoiding the leakage layer charge is no longer feasible, so that the score is the highest and is 5.

As can be seen from the upper rock mass parameter score table 1, when the properties of the rock are good, the corresponding rock mass parameter score is low; when the rock is judged to be a weak filling layer or a large crack, the corresponding rock mass parameter fraction is obviously improved; when the rock strength, the elastic modulus or the crack development condition reaches the maximum value of 5, the rock mass parameter value reaches the minimum value of 7 at the moment, namely the maximum value of 5 is reached at any condition, the other two items are the minimum value of 1, and the comprehensive condition of the rock mass is the worst at the moment; in addition, when other conditions reach 7, for example: in summary, in the blasting method of the present invention, it is determined that when the value of the rock mass parameter is 7 or more, the structural plane having a value of the rock mass parameter of 7 or more is a weak structural plane requiring grouting improvement, and the structural plane having a value of the rock mass parameter of 7 or more is a weak structural plane requiring grouting improvement.

Specifically, in the step S5, the specific method for determining the weak structural plane to be improved by cement grouting in the hard-hard structural plane interphase rock mass to be blasted according to the rock mass parameter score includes:

finding out the structural plane with the rock mass parameter value being more than or equal to 7 according to the rock mass parameter value corresponding to each structural plane in the hard-hard structural plane interphase rock mass to be blasted obtained in the step S4, wherein the structural plane with the rock mass parameter value being more than or equal to 7 is the soft structural plane which needs to be improved by grouting; when the parameter value of the rock mass is equal to 7, the condition that cement slurry needs to be poured is just met for the rock mass with the interphase hard and soft structural planes to be blasted.

Specifically, the concrete steps of step S6, determining the type of cement mortar to be poured into the weak structural plane to be improved by cement grouting according to the determined rock mass parameter value corresponding to the weak structural plane to be improved by cement grouting, are as follows:

s61, subtracting 4 from the rock mass parameter score F1 corresponding to the judged weak structural plane needing grouting improvement to obtain a corresponding cement paste improvement capacity score F2;

s62, making a cement paste improvement capability grading table, and marking out improvement capability scores corresponding to different water pump strengths and different additives, as shown in the following table 2:

TABLE 2 Cement paste improvement Capacity Scoring Table

In the above cement paste improvement capability score table 2, for the cement strength, the improvement capability scores corresponding to different cement strength grades are specifically as follows:

when the strength of the cement is more than or equal to 50MPa, the corresponding improving capability score is 5;

when the strength of the cement is less than 50MPa and more than or equal to 35MPa, the corresponding improving capability score is 3;

when the strength of the cement is less than 35MPa and more than or equal to 20MPa, the corresponding improving capability score is 2;

when the strength of the cement is less than 20MPa, the corresponding improving capability score is 1 score;

in the above cement slurry improvement capability score table 2, for the additives, the improvement capability scores corresponding to different additives are specifically as follows:

when the additive is fiber, the early strength agent and the expanding agent, the corresponding improving capability score is 5;

when the additive is an expanding agent and an early strength agent, the corresponding improving capability score is 3;

when the additive is an early strength agent, the corresponding improving capability score is 2 scores;

in the absence of additive, the corresponding improvement score is 1 score;

and S63, referring to the cement paste improvement capability score table formulated in the step S62, selecting the cement paste which can meet the cement paste improvement capability score condition obtained in the step S61 from the table, wherein the cement paste is the type of the cement paste which needs to be poured on the weak structural plane needing to be subjected to cement grouting improvement in the rock mass with the interphase hard and soft structural planes to be blasted.

As can be seen from the cement paste improvement capability score in Table 2, for the cement strength, when the cement is high-strength cement (not less than 50MPa), the corresponding improvement capability score is the highest and is 5 scores as the improvement effect is the best; when the strength of the cement is less than 20MPa, the cement can only play a role in filling cracks at the moment by adding the time required for the common cement to generate certain strength, so that the improvement effect is minimum, and the fraction of the corresponding improvement capacity is minimum and is 1 minute; the additive is the most effective in improving the tensile strength of cement paste by the fiber, and the cement improving effect can be exerted to the maximum extent by blending the early strength agent and the expanding agent, so that the corresponding improving ability is the highest score of 5.

In the process of practical tests, when the rock mass parameter fraction F1 is 7 minutes (namely the condition that cement slurry needs to be poured is just achieved), if cement with the pressure of less than 35MPa and more than 20MPa is adopted to be matched without additives, cracks can be filled and the strength and integrity of rocks are enhanced, or cement with the pressure of less than 20MPa is matched with an early strength agent to achieve similar effects. When the cement paste improvement capacity is graded in table 1 in comparison, it can be found that the cement with the strength of less than 35MPa and more than 20MPa is matched with the additive-free cement or the cement with the strength of less than 20MPa and matched with the early strength agent, the corresponding cement paste improvement capacity scores F2 are all 3 scores, and the score difference value of the rock parameter and the cement paste improvement effect at the moment is 4 (namely F1-F2); therefore, when the difference between the rock mass property coefficient and the cement slurry coefficient value of the hard-hard structural surface interphase rock mass to be blasted is 4, the blasting requirement can be met, and the condition is the condition for selecting cement slurry. Therefore, after the rock mass property coefficient is determined, the corresponding rock mass parameter value F1 is subtracted by 4 to select the corresponding cement mortar type to be poured on the weak structural plane needing to be improved by cement grouting.

As an example of the cementing apparatus used in step S7: referring to fig. 4 or fig. 9, it includes a grouting rod 1 and at least two expansion rubber sleeves 2 slidably sleeved on the grouting rod 1; a grouting channel 4 is further formed in the middle of the grouting rod 1 along the axial direction, a plurality of grouting ports 5 are further formed in the rod wall of the grouting rod 1 along the axial direction, and each grouting port 5 is communicated with the grouting channel 4 formed in the middle of the grouting rod 1; when the embodiment of the cement grouting device is used, each expansion rubber sleeve 2 is fixed on the outer rod wall of the grouting rod 1 through the positioning bolt 3, and the distance H between every two adjacent expansion rubber sleeves 2 is larger than or equal to the thickness of one weak structural surface needing to be improved by cement grouting in the rock mass with the interphase hard and soft structural surfaces to be blasted.

Specifically, the grouting rod 1 is formed by sequentially splicing a plurality of sections of grouting barrels 1.1 through a plurality of spiral rings 1.2. And the middle part of each grouting barrel 1.1 is provided with a grouting hole along the axial direction; a plurality of grouting openings 5 are formed in the wall of each section of grouting barrel 1.1 along the axial direction, and each grouting opening 5 in each section of grouting barrel 1.1 is communicated with a grouting hole correspondingly formed in the middle of the grouting barrel. When in use, as shown in fig. 5 and 6, grouting holes formed in the middle of each section of grouting cylinder 1.1 forming the grouting rod 1 are communicated with each other and form a grouting channel 4 formed in the middle of the grouting rod 1 along the axial direction.

Specifically, in the embodiment, before the cement grouting device is used, each grouting opening 5 on the grouting rod 1 is sealed or unsealed; when in use, the grouting rod 1 is not sealed except the grouting port 5 at the position where the expansion rubber sleeve 2 is sleeved, and the grouting ports 5 at other positions are sealed.

More specifically, in the embodiment, before the cement grouting device is used, each grouting opening 5 on the grouting rod 1 can be sealed by a sealant 6 or a detachable grouting valve 7; when the grouting device is used, the grouting openings 4 of the other parts of the grouting rod 1 are sealed by the sealant 6 except the grouting opening 5 at the part where the expansion rubber sleeve 2 is sleeved is not sealed.

In addition, the following description is provided: in the above embodiment, the length of the grouting rod 1 and the number of the expansion rubber sleeves 2 can be adjusted according to the geological condition (i.e. the rock stratum distribution condition) of the interphase rock mass of the hard and soft structural surfaces to be blasted; for example, as shown in fig. 2, when the rock body with the interphase soft and hard structural surfaces to be blasted has only one weak structural surface to be improved by grouting, the cement grouting device only needs two expansion rubber sleeves 2, and the distance between the two expansion rubber sleeves 2 is equal to or slightly larger than the thickness of the weak structural surface to be improved by grouting; when the rock body with the alternated soft and hard structural surfaces to be blasted has two soft structural surfaces to be improved by grouting (as shown in figure 3), the cement grouting device needs three or four expansion rubber sleeves 2, and the distance between every two adjacent expansion rubber sleeves 2 is equal to or slightly larger than the thickness of one soft structural surface to be improved by grouting.

The following two specific embodiments are respectively described, in the step S4, how to score the rock strength, elastic modulus and fracture development condition of each structural surface of the hard-hard structural surface interphase rock mass to be blasted and obtain the rock parameter scores corresponding to each structural surface of the hard-hard structural surface interphase rock mass to be blasted is specifically performed, in the step S5, according to the rock parameter scores, a weak structural surface, which needs to be improved by cement grouting, of the hard-hard structural surface interphase rock mass to be blasted is determined, in the step S6, according to the rock parameter scores corresponding to the determined weak structural surface, which needs to be improved by cement grouting, of the weak structural surface, which needs to be improved by cement grouting, is determined, and in the step S7, how to use a cement grouting device to perform cement grouting on the weak structural surface, which needs to be improved by cement, of the soft structural surface, of the hard-hard structural surface interphase rock mass to be blasted, of the soft structural surface, which needs to be improved by cement, of the soft And (3) treating: