坚硬岩层 meaning in English
competent bed
hard formation
sharp ground
Examples
- Skin impregnated drillbits are suitable for drilling in the medium - hard rock formation with f 6 - 10
表镶钻头适用于f 6 - 10机中硬及坚硬岩层的钻进 - Lung lok shui is a unique hard rock ridge found at tung ping chau . from a distance , it resembles a dragon charging into the sea
龙落水的岩质为燧石粉砂岩，从岛上高脊直奔入海，有如石龙奔海而名，是东平洲唯一及特有的坚硬岩层。 - Ball hob drill head is applicable for harden rock layer , fine grain granite , and it has below 9 - grade drillability . the compressive strength is no more than 15 of pull coefficient
球齿滚刀钻头适合于坚硬岩层，细晶花岗岩，可钻性9级以上，抗压强度在普氏系数15 。 - Abstract : main construction points of qingfang hospital station on qingdao subway under the condition of hard surrounding rock are described . blasting control and vibration monitoring are stressedly introduced
文摘:阐述了青岛地下铁道青纺医院车站在坚硬岩层中的施工要点，重点介绍了爆破控制、震动监测等内容，对于城市硬质岩石条件下的地下工程具有借鉴意义。 - By theoretical analysis and actual measurement of field and phenomena analysis of rock burst , the author illustrates the directionless pressure , sudden movement and rupture of hard roof lead to the internal cracks of coal instable development , which easily results in rock burst happening
摘要通过理论分析、现场实测和冲击矿压现象分析，说明了顶板坚硬岩层产生的静压和突然运动、破断均可使煤体内部裂纹不稳定扩展而容易发生冲击矿压。