英语翻译Compaction and GradingThe function of compaction equipme

英语翻译
Compaction and Grading
The function of compaction equipment is to produce higher density in soil mechanically.The basic forces used in compaction are static weight,kneading ,impact and vibration.The degree of compaction that may be achieved depends on the properties of soil ,its moisture content ,the thickness of the soil layer for compaction and the method of compaction.The function of grading equipment is to bring the earthwork to the desired shape and elevation.Major types of grading equipment include motor graders and grade trimmers.The former is an all-purpose machine for grading and surface finishing,while the latter is used for heavy construction because of its higher operating speed.
Drilling and Blasting
Rock excavation is an audacious task requiring special equipment and methods.The degree of difficulty depends on physical characteristics of the rock type to be excavated,such as grain size,planes of weakness,weathering,brittleness and hardness.The task of rock excavation includes loosening,loading,hauling and compacting.The loosening operation is specialized for rock excavation and is performed by drilling,blasting or ripping.
Major types of drilling equipment are percussion drillings,rotary drills,and rotary-percussion drills.A percussion drill penetrates and cuts rock by impact while it rotates without cutting on the upstroke.Common types of percussion drills include a jackhammer which is handheld others which are mounted on a fixed frame or on a wagon or crawl for mobility.A rotary drill cuts by turning a bit against the rock surface.A rotary-percussion drill combines the two cutting movements to provide a faster penetration in rock.

夯实和整地
夯实设备的作用是机械地增加砂土密度.夯实过程中的主要作用力包括净重力、揉捏、撞击及振动.可以实现的压实度等级取决于土质、含湿量、需压实的土层厚度和所采用的压实方法.
整地设备的主要作用是将土方塑成需要形状及标高.主要类型有发动机驱动整地机和整地浇灌机,前者为多用途的整地及表面平整机,而后者则因其高速操作特性被用于重型结构.
钻孔及爆破
岩石开挖工作风险相当大,要求有特殊开挖设备及开挖方法.难度等级取决于待开挖岩石物理特性：岩石晶粒度、脆弱面位、气候、脆度和硬度等.岩石爆破主要程序：碎石、装卸、拖运和压实.碎石工作为岩石爆破的特殊要求,通过钻孔、爆破或者劈石得以实现.