Method for construction of composite under-reamed pile and equipment thereof

A method for constructing a composite under-reamed pile, the method comprising:

• leveling a construction site and carrying out a survey for a position of a pile and a setting-out for positioning;
• forming, according to a pre-designed structure of the pile and through a jet grouting and agitation technology, composite cemented-soil foundations at pre-determined depths at the position of the pile, wherein:
• the jet grouting and agitation technology comprises grouting, with a pre-determined pressure, a medium to a soil of the construction site, and agitating the soil simultaneously, wherein the medium comprises a slurry medium or a powder medium;
• and
• the pre-determined depths comprise a depth position corresponding to a bulb in the pre-designed structure and/or a depth position corresponding to a pile end in the pre-designed structure;
• carrying out the survey again for the position of the pile after each of the composite cemented-soil foundations reaches a pre-determined strength;
• forming a pile hole for the pile in accordance with the pre-designed structure of the pile, wherein when the pre-designed structure comprises bulbs, forming a bulb cavity inside each of the formed composite cemented-soil foundations corresponding to the bulbs;
• and
• cleaning the pile hole, dipping a steel reinforcement cage and lowering a concrete pouring conduit into the pile hole, then lifting the pouring conduit upward along the pile hole while pouring the concrete, so that the inside of the pile hole and/or each of the bulb cavity are full-filled with the concrete, and then obtaining a pile body in the pile hole and the bulbs in each bulb cavity after the concrete is hardened;
• wherein when the pre-designed structure comprises a structure containing a single pile body, the forming the composite cemented-soil foundations at the pre-determined depths at the position of the pile according to the pre-designed structure, comprising:
• when the single pile body comprises at least one bulb, forming at least one bulb-position composite cemented-soil foundation at the pre-determined depth corresponding to the bulb, wherein each bulb-position composite cemented-soil foundation corresponds to the depth position of one the bulb;
• and
• when the single pile body comprises the pile end, forming one pile-end composite cemented-soil foundation at the pre-determined depth corresponding to the pile end, wherein the pre-determined depth corresponding to the pile end is a position of a pre-determined elevation of the pile end of the single pile body;
• wherein when the pre-designed structure comprises a structure containing multiple pile bodies, the forming the composite cemented-soil foundations at the pre-determined depths at the position of the pile according to the pre-designed structure, comprising:
• when at least two individual pile bodies in the multiple pile bodies comprise at least one bulb respectively, forming the bulb-position composite cemented-soil foundation at the pre-determined depth corresponding to each bulb, wherein formed bulb-position composite cemented-soil foundations at pre-determined depths corresponding to bulbs with a same pre-determined elevation form a bulb-position interconnected composite cemented-soil foundation by an interconnection therebetween;
• and
• when at least two individual pile bodies in the multiple pile bodies comprise the pile end respectively, forming the pile-end composite cemented-soil foundation at the pre-determined depth corresponding to each the pile end, wherein formed pile-end composite cemented-soil foundations at pre-determined depths corresponding to pile ends with the same pre-determined elevation form a pile-end interconnected composite cemented-soil foundation by an interconnection therebetween;
• wherein the forming the pile hole for the pile in accordance with the pre-designed structure of the pile, comprising:
• for the single pile body comprising at least one bulb, forming the pile hole by using a drilling rig and forming the bulb cavity in the bulb-position composite cemented-soil foundation by using a bulb cavity former alternately, and completing the pile hole until the drilling rig reaches an end of the single pile body after all bulb cavities being formed completely, obtaining the pile hole, and at least one the bulb cavity and at least one the bulb-position composite cemented-soil foundation distributed along the pile hole, wherein each bulb cavity being respectively embedded in a corresponding bulb-position composite cemented-soil foundation thereof;
• for the single pile body comprising the pile end, forming the pile hole by using the drilling rig, drilling and reaching to a pre-determined depth inside the pile-end composite cemented-soil foundation and completing the pile hole, and obtaining the pile hole and the pile-end composite cemented-soil foundation distributed at the end of the pile hole;
• and
• for the single pile body comprising at least one the bulb and the pile end, forming the pile hole by using the drilling rig and forming the bulb cavity in the bulb-position composite cemented-soil foundation by using the bulb cavity former alternately, and drilling and reaching to the pre-determined depth inside the pile-end composite cemented-soil foundation after all the bulb cavities being formed completely, and then completing the pile hole, obtaining the pile hole, at least one the bulb cavity and at least one the bulb-position composite cemented-soil foundation distributed along the pile hole, and the pile-end composite cemented-soil foundation distributed at the end of the pile hole, wherein each bulb cavity being respectively embedded in a corresponding bulb-position composite cemented-soil foundation thereof;
• and
• wherein the forming the pile hole for the pile in accordance with the pre-designed structure of the pile, further comprising:
• for the at least two individual pile bodies in the multiple pile bodies comprise at least one the bulb respectively, forming the pile hole for each individual pile body in the multiple pile bodies, wherein for the individual pile body, forming the pile hole by using the drilling rig and forming the bulb cavity in the bulb-position composite cemented-soil foundation, if the individual pile body has at least one the bulb, by using the bulb cavity former alternately, and completing the pile hole till the drilling rig reaches an end of the individual pile body after all bulb cavities being formed completely, obtaining the pile hole, and at least one the bulb cavity and at least one the bulb-position interconnected composite cemented-soil foundation distributed along the pile hole, wherein each bulb cavity being respectively embedded in a corresponding bulb-position interconnected composite cemented-soil foundation thereof;
• for the at least two individual pile bodies in the multiple pile bodies comprise the pile end respectively, forming the pile hole for each the individual pile body in the multiple pile bodies, wherein for the individual pile body, forming the pile hole by using the drilling rig, drilling and reaching to the pre-determined depth inside the pile-end interconnected composite cemented-soil foundation and completing the pile hole, and obtaining the pile hole and the pile-end interconnected composite cemented-soil foundation distributed at the end of the pile hole;
• and
• for the at least two individual pile bodies in the multiple pile bodies comprise at least one the bulb and the pile end respectively, forming the pile hole for each the individual pile body in the multiple pile bodies, wherein for the individual pile body, forming the pile hole by using the drilling rig and forming the bulb cavity in the bulb-position composite cemented-soil foundation, if the individual pile body has the at least one the bulb, by using the bulb cavity former alternately, and completing the pile hole by drilling and reaching to the pre-determined depth inside the pile-end interconnected composite cemented-soil foundation after all bulb cavities being formed completely, obtaining the pile hole, at least one the bulb cavity and at least one the bulb-position interconnected composite cemented-soil foundation distributed along the pile hole, and the pile-end interconnected composite cemented-soil foundation distributed at the end of the pile hole, wherein each bulb cavity being respectively embedded in a corresponding bulb-position interconnected composite cemented-soil foundation thereof;
• and
• wherein the forming the pile hole by using the drilling rig and forming the bulb cavity in the bulb-position composite cemented-soil foundation by using the bulb cavity former alternately, comprising:
• firstly, drilling the pile hole by using the drilling rig, when the drilling rig reaches inside the bulb-position composite cemented-soil foundation, stopping and removing the drilling rig, forming the bulb cavity inside bulb-position composite cemented-soil foundation by using the bulb cavity former, after the bulb cavity is formed, stopping and removing the bulb cavity former, continuing to drill the pile hole by using drilling rig, repeating the above steps if there are more than one the bulb cavity need to be formed inside corresponding bulb-position composite cemented-soil foundation thereof, until all the bulb cavities are formed completely.