A pile to be inserted into a beforehand excavated hole, includes a main body being comprised of a hollow pipe, a circular bottom plate fixed at a lower end of the main body coaxially with the main body, a through-hole being formed therethrough outside of the main body, a hollow test pipe having an outer diameter such that the test pipe can be detachably inserted into the through-hole, and a cap being attached to a lower surface of the bottom plate so as to close the through-hole, S1:S2=W1:W2, wherein S1 indicates a surface area of the bottom plate, S2 indicates a surface area of the cap, W1 indicates a weight of a second drop hammer to fall in the main body, and W2 indicates a weight of the first drop hammer.

A pile to be inserted into a beforehand excavated hole, includes a main body being comprised of a hollow pipe, a circular bottom plate fixed at a lower end of the main body coaxially with the main body, a through-hole being formed therethrough outside of the main body, a hollow test pipe having an outer diameter such that the test pipe can be detachably inserted into the through-hole, and a cap being attached to a lower surface of the bottom plate so as to close the through-hole, S1:S2=W1:W2, wherein S1 indicates a surface area of the bottom plate, S2 indicates a surface area of the cap, W1 indicates a weight of a second drop hammer to fall in the main body, and W2 indicates a weight of the first drop hammer.

A pile to be inserted into a beforehand excavated hole, includes a main body being comprised of a hollow pipe, a circular bottom plate fixed at a lower end of the main body coaxially with the main body, a through-hole being formed therethrough outside of the main body, a hollow test pipe having an outer diameter such that the test pipe can be detachably inserted into the through-hole, and a cap being attached to a lower surface of the bottom plate so as to close the through-hole, S1:S2=W1:W2, wherein S1 indicates a surface area of the bottom plate, S2 indicates a surface area of the cap, W1 indicates a weight of a second drop hammer to fall in the main body, and W2 indicates a weight of the first drop hammer.

A pile to be inserted into a beforehand excavated hole, includes a main body being comprised of a hollow pipe, a circular bottom plate fixed at a lower end of the main body coaxially with the main body, a through-hole being formed therethrough outside of the main body, a hollow test pipe having an outer diameter such that the test pipe can be detachably inserted into the through-hole, and a cap being attached to a lower surface of the bottom plate so as to close the through-hole, S1:S2=W1:W2, wherein S1 indicates a surface area of the bottom plate, S2 indicates a surface area of the cap, W1 indicates a weight of a second drop hammer to fall in the main body, and W2 indicates a weight of the first drop hammer.

Apparatuses for constructing displacement aggregate piers are disclosed. In one example, a mandrel is provided comprising a tamper head that has cutting teeth on the leading edge thereof. In another example, hydrojet nozzles are provided within one or more of the cutting teeth of the tamper head. In yet another example, the mandrel comprises grout tubes (or grout injection lines) and/or grout inspection lines. In yet another example, the mandrel and/or tamper head can comprise cutting teeth, hydrojet nozzles, grout tubes (or gout injection lines), grout inspection lines, and any combinations thereof.

Apparatuses for constructing displacement aggregate piers are disclosed. In one example, a mandrel is provided comprising a tamper head that has cutting teeth on the leading edge thereof. In another example, hydrojet nozzles are provided within one or more of the cutting teeth of the tamper head. In yet another example, the mandrel comprises grout tubes (or grout injection lines) and/or grout inspection lines. In yet another example, the mandrel and/or tamper head can comprise cutting teeth, hydrojet nozzles, grout tubes (or gout injection lines), grout inspection lines, and any combinations thereof.

A drive point for a substantially tubular driven pile, wherein the drive point can be fitted onto a pile end of the driven pile, wherein at least one first support limb with a first support surface configured to abut an end face of the pile end of the driven pile is arranged at an inside wall of the drive point, wherein at least one support device with a ground surface is arranged at an outer surface of the drive point, and wherein the ground surface of the at least one support device supports the drive point when on a ground into which the drive point is to be driven in a driving-in direction.

An aggregate pier compacting system for forming a compacted aggregate pier (AP) at a target location includes a mandrel, a tamper device, and a finishing tamper device. The mandrel includes a casing for housing a drilling shaft (DS). An external vibratory hammer (EVH) repeatedly impacts a hammer element (HE) extending from the DS. The DS transfers the impact to a bore head to form a cavity at the target location. The DS is removed and the casing is filled with aggregate. The tamper device includes a compacting shaft. The EVH impacts a second HE extending from the compacting shaft and transfers the impact to a compaction head to form the compacted AP. The finishing tamper device includes a shaft. The EVH impacts a third HE extending from the shaft and transfers the impact to a finishing head compacting a top layer of the AP to form a finished AP.

An aggregate pier compacting system for forming a compacted aggregate pier (AP) at a target location includes a mandrel, a tamper device, and a finishing tamper device. The mandrel includes a casing for housing a drilling shaft (DS). An external vibratory hammer (EVH) repeatedly impacts a hammer element (HE) extending from the DS. The DS transfers the impact to a bore head to form a cavity at the target location. The DS is removed and the casing is filled with aggregate. The tamper device includes a compacting shaft. The EVH impacts a second HE extending from the compacting shaft and transfers the impact to a compaction head to form the compacted AP. The finishing tamper device includes a shaft. The EVH impacts a third HE extending from the shaft and transfers the impact to a finishing head compacting a top layer of the AP to form a finished AP.

Apparatuses for constructing displacement aggregate piers are disclosed. In one example, a mandrel is provided comprising a tamper head that has cutting teeth on the leading edge thereof. In another example, hydrojet nozzles are provided within one or more of the cutting teeth of the tamper head. In yet another example, the mandrel comprises grout tubes (or grout injection lines) and/or grout inspection lines. In yet another example, the mandrel and/or tamper head can comprise cutting teeth, hydrojet nozzles, grout tubes (or grout injection lines), grout inspection lines, and any combinations thereof.