Major part back-up sand pile for prestressed pipe
Utility model major part back-up sand pile for prestressed pipe relates to the civil construction field, relates in particular to the building foundation engineering field.
As everyone knows, in building foundation engineering, pile for prestressed pipe is low with cost, the duration is short, the construction plant is clean and be widely used.But existing pile for prestressed pipe its internal diameter, external diameter and wall thickness in same joint all equate from top to bottom, China's coastal cities multidigit is in estuary bay, be soft foundation, the soil layer collateral resistance is little, bearing capacity of single pile is not high, make pile shaft material intensity to make full use of and waste, cause the Foundation Design cost high.
The purpose of this utility model provides major part back-up sand pile for prestressed pipe, can improve bearing capacity of single pile significantly under equal geological conditions, pile shaft material intensity can be given full play to, thereby reduce the total amount of pile of building, reaches and reduces the Foundation Design cost.
The purpose of this utility model is achieved through the following technical solutions: major part back-up sand pile for prestressed pipe is the same with prior art, the tubulose pile body that all includes prestressed reinforced concrete, it is characterized in that: at pile tube stake end, the stake major part of prefabricated separately steel concrete or concrete or steel is arranged, and the stake diameter at butt end is greater than tubular pile body diameter 8-40cm; At tubular pile body, every 1-7m, concrete or the steel concrete rib of the wide 5-25cm of a protrusion, high 5-20cm arranged, two intercostal back-up sand or gravels, the cross section of rib are trapezoidal, isosceles trapezoid or right-angled trapezium; The soil compaction effect that causes of piling and discharge soil layer mesopore water pressure as early as possible can be provided with the vertical drainage hole of 1-10 diameter 0.5-3cm in rib.
The utility model compared with prior art has following conspicuous advantage: it can increase substantially bearing capacity of single pile under equal geological conditions, reduce the stake number, reduces construction costs, promotes soil layer to solidify, and improves soil layer intensity.The utility model is applicable to the building foundation engineering of soft foundation.
Description of drawings:
Fig. 1 is the generalized section of the utility model embodiment.
Fig. 2 is the floor map (a is the closing pile point, and c is an opening stake point) and the generalized section (b is the closing pile point, and d is an opening stake point) of steel concrete of the present utility model or concrete pile major part.
Fig. 3 is steel stake major part floor map of the present utility model (a) and generalized section (b).(1) is stake major part end plate among the figure, and (2) are the wing of putting more energy into, and (3) are ring.
An exemplary embodiments of the present utility model such as Fig. 1: produce required pile tube with ribbing (1) by pile tube manufactory earlier, (5) and the stake major part (6), treat to transport the job site to after intensity reaches, stake major part (6) is placed on the stake position, hang first segment pile tube (5) and stand on a major part (6) center, the all heap sands of stake, piling (or piling) limit, limit constantly adds sand, by managing rib (2) with abrasive band underground layer (9), (8), (7) in, form stake all back-up sand layers (3), first segment pile tube (5) is sink to ground, it is placed on it to hang the second pipe joint stake (1), and electric welding joins, and it squeezed into soil layer (9) again, (8) in until design elevation, like this, just finish the making construction of a major part back-up sand pile for prestressed pipe, the pressure pore water that pile sinking causes is discharged ground by the drain hole (4) in back-up sand layer (3) and the rib (2).Go round and begin again, finish the making and the construction of all required major part back-up sand pile for prestressed pipe.