强夯地基施工工艺标准
Construction technology standard of dynamic compaction Foundation
1  适用范围
1 scope of application
本标准适用于采用强夯加固地基施工的工程。当强夯所产生的振动，对现场周围已建成或正在施工的建筑物或构筑物有影响时不得采用，必须采用时应采取防振措施。
This standard is applicable to the construction of foundation reinforcement by dynamic compaction. When the vibration produced by dynamic compaction has an impact on the buildings or structures built or under construction around the site, vibration prevention measures shall be taken when necessary.
2  施工准备
2 construction preparation
2.1  主要施工机具
2.1 main construction equipment
2.1.1  夯锤
2.1.1 rammer
强夯锤锤重可取10～40t，底面形式宜采用圆形或多边形。夯锤的材质最好为铸钢，如条件所限，则可用钢板壳内填混凝土。夯锤底面宜对称设置若干个φ250～300mm与顶面贯通的排气孔，以利于夯锤着地时坑底空气迅速排出和起锤时减小坑底的吸力。锤底面积宜按土的性质确定，对于砂质土和碎石填土，采用底面积为2～4m2较为合适；对于一般第四纪粘性土建议用3～4m2；对于淤泥质土建议采用4～6m2为宜。锤底静接地压力值可取25～40kPa，对于细颗粒土锤底静接地压力宜取较小值。
The weight of dynamic rammer is 10-40t, and the bottom form should be round or polygonal. The rammer should be made of cast steel. If the condition is limited, concrete can be filled into steel plate shell. The bottom surface of the rammer should be symmetrically arranged with a number of vent holes with a diameter of 250-300 mm through the top surface, so as to facilitate the rapid discharge of air at the bottom of the pit when the rammer hits the ground and reduces the suction at the bottom of the pit when the hammer is lifted. The hammer bottom area should be determined according to the nature of soil. For sandy soil and gravel fill, the bottom area of 2-4m2 is more appropriate; for general quaternary cohesive civil engineering, it is recommended to use 3-4m2; for muddy soil, it is recommended to use 4-6m2. The value of static grounding pressure at hammer bottom can be 25 ~ 40kpa, while for fine-grained soil, it should be smaller.
2.1.2  起重机具
2.1.2 lifting equipment
宜选用15t以上的履带式起重机或其他专用的起重设备。当起重机吨位不够时，亦可采取加钢支腿的方法，起重能力应大于夯锤重量的1.5倍。采用履带式起重机时，可在臂杆端部设置辅助门架，或采用其他安全措施，防止落锤时机架倾覆。
Crawler crane of 15t or above or other special lifting equipment should be selected. When the tonnage of the crane is not enough, the method of adding steel legs can be adopted. The lifting capacity should be 1.5 times of the weight of the rammer. When crawler crane is used, auxiliary gantry can be set at the end of boom, or other safety measures can be taken to prevent the frame from overturning when falling hammer.
2.1.3  脱钩器：要求有足够强度，起吊时不产生滑钩；脱钩灵活，能保持夯锤平稳下落，同时挂钩方便、迅速。
2.1.3 decoupler: it is required to have sufficient strength and not produce sliding hook during lifting; the decoupling device is flexible and can keep the hammer falling down smoothly, and the hook is convenient and rapid.