Construction method of compact underwater rubble bed

Abstract

The invention discloses a construction method of a compact underwater rubble bed, which comprises the steps of: 1) accepting a base groove; 2) riprapping a bed; 3) measuring cross section of the bed before blasting; 4) positioning by a positioning boat; 5) artificially adding and arranging explosive; 6) blasting in various sections and various regions; 7) measuring the cross section of the bed after blasting; and 8) detecting and accepting. The construction method of the compact underwater rubble bed is low in requirement on locating precision; the construction method just needs to distribute explosive packages in the region rather than precisely arrange the explosive packages on a fixed point, and is unnecessary to pre-level, therefore, the construction is simple; the explosive demand is lower and the explosive amount is reduced by 20-40%, to reduce harmful influence of the blasting on the surrounding environment; fewer processes are required, the explosive package is simple to arrange, the economic performance is good and the cost is lower; since the explosive package is arranged in a manner to contacting to the earth, the stability of the explosion propagation network is good and the anti-explosion rate is low; and the construction quality is good, and the rubble body is compact and reliable.

Description

Technical field [0001] The invention relates to a construction method, in particular to a method for compacting an underwater riprap base bed. Background technique [0002] During the construction of port hydraulic structures, some large-scale gravity wharves, revetments and other gravity structures often use underwater riprap base beds. When these base beds are thick (generally greater than 2m), follow the "gravity wharf The requirements of "Design and Construction Code" JTS167-2-2009 (hereinafter referred to as "Code") should be consolidated. There are only two methods for subsoil compaction in China: "hammer compaction" and "explosive compaction". [0003] (1) Brief description of "hammer tamping" construction method: [0004] The "hammer tamping" construction is made by a large dredger or crane vessel with a rammer, and GPS measurement and positioning are used to fix the rammer ship above the design ramming point of the riprap base bed in a figure eight anchoring method. Befor...

AI Technical Summary

Problems solved by technology

The disadvantages of explosive ramming are: 1. It is difficult to locate. The explosive ramming of the foundation bed requires the plane position of the charge package to be within ±10% a, where a is the grid side length, generally 2m-5m, and the allowable deviation is 0.2m-0.5m. Requirements are difficult to meet during construction

The construction environment of explosive ramming generally has a water depth of more than 10m, and the conditions of water flow and wave are relatively complicated. The method of distributing medicines is mostly manually dropped or dropped to the bottom with artificial pull ropes, and it is difficult to achieve the required accuracy.

2) The reliability of the quasi-explosion is poor, and the explosive ramming charge must have a hanging height under water. Since the charge is suspended in the water, under the action of the water flow, the stress on the explosive ramming network is complicated, and the network is easily damaged. The rate is low, and the number of rejected explosives is large, which affects the construction quality

3) The amount of explosives is large, the cost is relatively high, and the unit consumption of explosives for foundation bed blasting is large. The foundation bed that requires leveling needs to be pre-leveled before blasting, and the construction cost is high.

4) It has a great impact on the surrounding environment. Due to the large amount of single-powder packaged in the explosive ramming of the foundation bed, the harmful effects such as earthquakes and shock waves generated by the explosion will be large, and the impact on the environment will be great.

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