It has always been a difficult problem to determine the safety interval of vibration during the construction of dynamic compaction machine, which involves the determination of Safety specifications, the characteristics of foundation soil, the size of dynamic compaction function level, the size of rammer area and many other elements. It is difficult to give proper data without on-site vibration inspection, but not every project has the conditions to do on-site vibration inspection, especially in the initial stage of foundation treatment plan.
强夯机产生的振动有以下几点规律:
The vibration produced by dynamic compaction machine has the following rules:
1)强夯机振动主频率一般在50Hz以下,且跟着间隔的增大而减小。
1) The main frequency of dynamic compaction machine vibration is generally below 50 Hz, and decreases with the increase of interval.
2)强夯机振动的震波在短间隔内主要以面波的办法向周围松散。振动强度跟着距振源点间隔的增大而衰减。振动强度的衰减速率和地基土的特性有关。当地基土层脆弱、松懈、密实度低、厚度大时,振动强度衰减活络;当地基土层稳固密实或土层脆弱厚度薄、下卧土层稳固时,振动强度衰减较慢。
2) In a short interval, the vibration wave of dynamic compaction machine is mainly loose to the surrounding by surface wave. The vibration intensity decreases with the increase of the distance from the vibration source. The attenuation rate of vibration intensity is related to the characteristics of foundation soil. When the local foundation soil layer is fragile, lax, low density and thick, the vibration intensity is attenuated and active; When the local foundation soil layer is stable and dense, or the soil layer is fragile and thin, and the underlying soil layer is stable, the vibration intensity attenuation is slow.
3)强夯机振源点坐落相对标高低处时,在相对标高较高处的振动效应是扩展;强夯机振源点坐落相对标高较高处时,在相对标高较低处的振动效应是衰减。
3) When the vibration source point of dynamic compaction machine is located at the lower part of the relative elevation, the vibration effect at the higher part of the relative elevation is expanding; When the vibration source point of dynamic compaction machine is located at the higher relative elevation, the vibration effect at the lower relative elevation is attenuation.
4)强夯机振动强度跟着能级的增大而增大,跟着夯锤面积的减小而减小。
4) The vibration intensity increases with the increase of energy level and decreases with the decrease of hammer area.
强夯机主要用于建筑方面,而对于强夯机所在进行施工中由于土壤压实机的需要,往往采用强夯机压实机械的类型有很多,一只青蛙,振动型,一步一步,夯实,吊锤锤式,根据工程需要,所以运用不同类型的强捣固机,固定地基的好帮手。
Dynamic compaction machine is mainly used in construction. Due to the need of soil compactor, dynamic compaction machine is often used in the construction of dynamic compaction machine. There are many types of compaction machine, such as frog, vibration type, step by step, tamping, hanging hammer type. According to the needs of the project, different types of dynamic compaction machine are used to fix the foundation.
另外还有一方面,则针对强夯机的应用,其主要是由一些高冲击锤的高度可以是物质的砾石,碎石,炉渣,对地基强度性能较好,地基中形成颗粒墩,墩墩复合地基的形成,从而为了方便,以提高地基承载力,减少沉降。在动力置换过程中,土体结构遭到破坏,地基土产生超静孔隙水压力,但随着时间的推移土体结构强度会恢复。粒状桥墩一般具有良好的透水性,有利于超孔隙水压力消散和固结。
On the other hand, for the application of dynamic compaction machine, it is mainly composed of some high impact hammer, the height of which can be material gravel, crushed stone and slag. It has good strength performance for the foundation, the formation of granular pier in the foundation and the formation of pier pier composite foundation, so as to improve the bearing capacity of the foundation and reduce the settlement for convenience. In the process of dynamic replacement, the soil structure is destroyed, and the foundation soil produces excess pore water pressure, but with the passage of time, the soil structure strength will recover. Granular piers generally have good permeability, which is conducive to dissipation and consolidation of excess pore water pressure.