Tunnel blasting vibration reduction structure in urban sensitive area

Abstract

The utility model belongs to the technical field of tunnel construction, and particularly relates to an urban sensitive area tunnel blasting vibration reduction structure. Comprising two rows of vibration reduction holes formed in the arch portion of a tunnel, hole positions of the two rows of vibration reduction holes are arranged in a staggered mode, the two rows of vibration reduction holes are parallel to the axial direction of the tunnel, the length of each sequence of vibration reduction holes is 10-12 m, and the front sequence of vibration reduction holes and the rear sequence of vibration reduction holes are in lap joint by 1.5 m in the length direction; according to the tunnel blasting vibration reduction structure in the urban sensitive area, the blasting vibration speed at the position of a protected object can be reduced by about 30%, the vibration influence of tunnel blasting operation on the surrounding environment is remarkably reduced, and sensitive facilities such as gas pipelines are protected against damage.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of tunnel construction, and particularly relates to a tunnel blasting vibration reduction structure in a sensitive urban area. BACKGROUND

[0002] In cities such as Qingdao, where the geological stratum is mainly rock, the construction of a subway station often requires excavation work in hard rock stratum, and the blasting method is the first choice due to its high efficiency. However, these areas are usually accompanied by dense buildings, municipal pipelines and key infrastructure, such as gas pipelines, which pose a high challenge to blasting vibration control. In particular, at the starting section of the station construction inclined shaft tunneling, due to the shallow burial depth and close proximity to the sidewalk, the blasting operation has a particularly significant impact on the vibration of the surrounding environment. If vibration control is not properly controlled, it can easily lead to accidents such as pipeline damage and building cracking, not only affecting construction progress, but also posing a serious threat to public safety.

[0003] Currently, tunnel blasting vibration reduction mainly relies on traditional methods such as optimizing the slotting form and controlling the maximum single segment charge. Although these methods can achieve certain vibration reduction effect under normal conditions, in extreme cases such as a gas pipeline adjacent to the initiation point and the charge amount reduced to the minimum, the vibration reduction effect is limited and cannot meet the strict vibration control requirements. Therefore, it is particularly important to explore a more efficient and reliable blasting vibration control measure. SUMMARY

[0004] An object of the present utility model is to solve at least the above problems and provide at least the advantages described later.

[0005] The utility model provides the following technical scheme: a tunnel blasting vibration reduction structure in a sensitive urban area, comprising two rows of damping holes arranged in the tunnel arch, the hole positions of the two rows of damping holes are staggered, both rows of damping holes are parallel to the tunnel axis, the length of each sequence damping hole is 10-12m, and the front and rear two sequences of damping holes overlap by 1.5m in the length direction.

[0006] Further, the row of damping holes of the outer circle is aligned with the row of blasting holes of the outermost circle of the tunnel section, and the vertical spacing between the row of damping holes of the inner circle and the row of damping holes of the outer circle is 300-400mm.

[0007] Further, the diameter of the damping hole is 100-130mm.

[0008] Further, the ring spacing between the row of damping holes of the outer circle is 300mm, and the row of damping holes of the inner circle is located between every two of the row of damping holes of the outer circle.

[0009] Further, the two rows of damping holes of the tunnel arch are distributed symmetrically about the tunnel centerline.

[0010] Compared with the prior art, the advantages of this utility model are:

[0011] This utility model provides a vibration reduction structure for tunnel blasting in sensitive urban areas. It can reduce the blasting vibration velocity at the protected location by approximately 30%, significantly reducing the vibration impact of tunnel blasting operations on the surrounding environment and protecting sensitive facilities such as gas pipelines from damage. The vibration reduction hole arrangement is simple and clear, and the construction method is mature and reliable, without significantly affecting the original construction process. It is particularly suitable for vibration control during tunnel blasting in sensitive urban areas and has high application value. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the cross-sectional arrangement of the vibration damping holes;

[0013] Figure 2 This is a schematic diagram of the longitudinal section arrangement of the vibration damping holes.

[0014] In the diagram: 1-Vibration damping hole; 2-Blast hole; 3-Tunnel outline. Detailed Implementation

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] like Figure 1 , Figure 2 As shown: A vibration reduction structure for tunnel blasting in a sensitive urban area includes two rows of vibration reduction holes 1 arranged in the tunnel arch. The holes 1 of the two rows are staggered. The vibration reduction holes 1 are used to block and disperse blasting stress waves to achieve efficient control of blasting vibration. This allows seismic waves passing through the vibration reduction holes 1 to travel at a low amplitude, reducing the blasting vibration velocity at the protected location. Both rows of vibration reduction holes 1 are parallel to the tunnel axis. The length of each sequence of vibration reduction holes 1 is 10-12m. The two sequences of vibration reduction holes 1 overlap by 1.5m in the length direction to ensure continuous and effective attenuation of vibration waves during propagation.

[0017] The outer row of vibration-damping holes 1 is aligned with the outermost row of blasting holes 2 on the tunnel cross-section. The vertical distance between the inner row of vibration-damping holes 1 and the outer row of vibration-damping holes 1 is 300-400mm. The diameter of each vibration-damping hole is 100-130mm. The circumferential spacing between the outer row of vibration-damping holes 1 is 300mm, and the inner row of vibration-damping holes 1 is located between each pair of the outer row of vibration-damping holes 1. The two rows of vibration-damping holes in the tunnel arch are symmetrically distributed about the tunnel centerline to maximize the vibration reduction effect.

[0018] By implementing the damping structure, the blasting vibration velocity of the protected object position can be reduced by about 30%, the vibration influence of the tunnel blasting operation on the surrounding environment is significantly reduced, and sensitive facilities such as gas pipelines are protected from damage.

[0019] The damping hole construction steps include:

[0020] Construction preparation: the survey personnel accurately determine the plane position and inclination of the damping hole on the tunnel face according to the damping hole layout, and number each hole. At the same time, technical briefing is carried out to ensure that the construction personnel understand the construction requirements and ensure the realization of the design intention.

[0021] Drilling machine positioning and adjustment: the drilling machine is supported on a stable foundation to prevent sinking, swinging or displacement. The position of the drilling machine is accurately determined by using the theodolite, wire hanging, drill rod guide and other methods to ensure that the drill rod axis is consistent with the damping hole axis.

[0022] Drilling operation: the drill rod connecting sleeve is made of the same material as the drill rod, and the minimum wall thickness is greater than or equal to 10 mm, so as to ensure that the drill rod joint has sufficient strength, stiffness and toughness. The drilling direction is accurately determined by using the extension of the drill rod and the plumb bob, and the maximum sinking amount and left-right deviation of the drilling machine are controlled to be about 1% of the length of the damping hole. The drilling speed is moderate when the hole is opened, and the normal drilling speed is turned on after drilling to a depth of 20 cm. During the drilling process of the drill rod, it is necessary to check whether the drill rod is bent or damaged, etc., and replace it in time if it does not meet the requirements. The hole position is measured frequently by using the inclinometer during the drilling process to ensure the quality of the formed hole. At the same time, the geological conditions during the drilling process are recorded to provide reference for geological prediction and prediction of the tunnel excavation.

[0023] Hole cleaning and inspection: use the geological core drill rod to cooperate with the drill bit to repeatedly sweep the hole and remove dross. Use high-pressure air to clean the drilling slag from the bottom of the hole to the opening. Finally, use the theodolite, inclinometer and other instruments to detect the hole depth and inclination to ensure that the hole diameter and depth meet the requirements.

[0024] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application should not be limited to the embodiments shown herein, but should be consistent with the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A vibration reduction structure for tunnel blasting in a sensitive urban area, characterized by: The two rows of damping holes (1) are arranged on the tunnel arch, the hole positions of the two rows of damping holes (1) are staggered, the two rows of damping holes (1) are parallel to the tunnel axis, the length of each damping hole (1) is 10-12 m, and the front and rear damping holes (1) are overlapped by 1.5 m in the length direction.

2. The vibration reduction structure for tunnel blasting in urban sensitive areas according to claim 1, characterized in that: The row of damping holes (1) of the outer ring is aligned with the row of blasting holes (2) of the outermost section of the tunnel, and the vertical spacing between the row of damping holes (1) of the inner ring and the row of damping holes (1) of the outer ring is 300-400 mm.

3. The vibration reduction structure for tunnel blasting in urban sensitive areas according to claim 2, characterized in that: The diameters of the damping holes are all 100-130 mm.

4. The vibration reduction structure for tunnel blasting in urban sensitive areas according to claim 3, characterized in that: The circumferential spacing between the row of damping holes (1) of the outer ring is 300 mm, and the row of damping holes (1) of the inner ring is located between every two damping holes (1) of the outer ring.

5. The vibration reduction structure for tunnel blasting in urban sensitive areas according to claim 1, characterized in that: The two rows of damping holes of the tunnel arch are symmetrically distributed about the tunnel center line.

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