US1794892A

US1794892A - Forming piles

Info

Publication number: US1794892A
Application number: US605828A
Authority: US
Inventors: John B Goldsborough
Original assignee: Individual
Current assignee: Individual
Priority date: 1922-12-09
Filing date: 1922-12-09
Publication date: 1931-03-03
Anticipated expiration: 1948-03-03

Description

March 3, l931- J. B. GoLDsBoRouGH 1,794,892

FORMING PILES Filed DGO. 9, 1922 E; .5. E197 Eggs.

A TTORNEYS.

Patented Mar. 3, 1931 c PATENT orf-ICE y -JOHN B. GOLDSBOROUGH, OF CBOTON-ON-HUDSON, NEW YORK FOBIING PILES Application mea member e, 192s. serial No. 605,828.

This invention relates to the formation of piles, particularly of the type consisting of a metallic tube or shell embedded in the ground and lled with concrete or other foundation material.

ln some cases the shells for piles of this character are driven with the `lower end open,

but in such cases it is necessary to clear out the shell in order that it may be filled with foundation material. This clearing opera-- tion is expensive and causes a delay -rn the preparation of the foundations for the building to be subsequently erected In order to avoid the disadvantages attending the driving of shells in open condition various forms of drivin points for closing the lower ends of the she ls have been proposed and some have been used. These driving points are usually of heavy cast iron,

2o are expensive to manufacture and must be produced in as many sizes as there are die ameters of shells. It is usually necessary to order them sometime in advance of the time when they will be required, in order that they may be on hand when needed to avoid any delay in preparing the foundations. A further disadvantage of the use of such driving points is the reduced load value of the piles with which they are associated, when they are driven to rock, due to the relatively small area of contact between the driving point and the rock, this reduction amounting in some cases to as much as two-thirds of the bearing value which the pile would have if the area of its entire lower end were in contact with the rock.

Another method which is frequently used for avoiding the necessityv for clearing out the shells after they have been sunk is to employ a Spud or plunger substantially filling the shell and having a pointed lower end projecting beyond the bottom of the shell. The use of a spud or plunger is attended with diliiculties when employed for sinking open ended shells in wetl ground, for the suctlon effect caused by the removal of the Spud or lunger resultsin the shell being more or ess filled with earth andl water after the spud or plunger has been removed. The shell cannot satisfactorily be lfilled with concrete under such conditions.

' The use of a spud or plungerv for sinking a shell is attended with a further disadvantage due to the increased headroom required to insert the spud within the shell before the latter is driven into the round due to the fact that it is necessary to ift the spud above the top of the shell in order to drop it into the latter.

This invention has for its general object the avoidance of the disadvantages of prior methods of forming piles of the general char acter referred to above, as well as the simplification and lessening of the cost of forming such piles. These and other objects of the invention are attained b closing the lower end of the shell with a at cap .preparatory to sinking it and by erformin the sinking operation without t e use o a spud or plunger, thereby keeping the shell clear and eliminatin the necessity for providing the extra hea -room which is required when shells are .sunk by means of spuds placed within them. This reduction of the headroomvis of particular advantage, as the cost and diiculty of handlino' driving apparatus increases greatly if the height of the appa-I ratus is increased above that re uired' for sinking shells of ordinary length y a driving device acting directly upon the top of the shell without the use of a Spud.

' After the shell has been sunk in the ground in the manner above described, the concrete is poured into the shell to form a cased shell. or the driving form or shell may be removed in the manner well known to those skilled in the art.

The caps for closing the lower ends of the shells may be formed of sheet metal which is cheap and easily obtainable and they may be particular sizes of pipes which are being used as 'shells for the p1le`s, the expense of carry-l ing in stock a number of different sizes, as

vis necessary' in the case of driving points, is

avoided.

hammer 3 of such apparatus. Closing the lower end ofthe pile shell 1 is a cap 4-having properties peculiarly suiting it to facilitate the advance of the ile shell through the earth. As shown in IFigs. 2 and 9, the'cap has a flat web circumscribed by an upturned flange 5 adapted to fit around the bottom of the shell 1. l; Y

By reason of the fact that the upturned flange encloses the lower end ofthe driving form or shell, the penetrating head is of greater area than that of the lower end of the The present improvement is also particu\ driving form, thereby providing a footing of larly adapted for use in cases in which a bulb darger area for the pile than that of the lower is to be formed at the lower end of the pile by expellingsuccessive charges of material from the shell until a bulb of the required size has .been produced'. The initial chargeof ma 4terial as it is expelled from the shellcarries with it the cap which remains permanently `embedded below the bulb to reinforce thel footing of the latter.

The facility with which a shell provided with a flat closure for its lower end may be driven into the ground appears to be due i-n large measure to the formation below the closure of a cone-like mass of closely compacted soil which acts 4as a; driving point thereby facilitating' the penetration of the shell into the ground in a manner analogous to that which occurs when a heavy metallic driving point is'employed.

The particular nature of the invention as well as other objects and advantages thereof will appear more clearly from a description of certain preferred embodiments as yshown in the accompanying drawings in which- Fig. 1 is a side elevation, showing pile-driving apparatus about to sink a pile tube.

Fig. 2 is an enlarged view in vertical section, showing a pile tube about to be sunk by my improved method; IFig. 3 is a similar view, showing the pile tube inits course of descentinto the earth;

Fig. 4 is a vertical section, disclosing the sunken pile tube, a bulb-foot-forming charge being shown at the bottom of the tube and about to be acted .upon by a rammer;

Fig. 5 is a like view, but depicting the condition after the rammer has acted;

Fig. 6 shows a concrete pile with a bulb footing formed by the action of the rammer on repeated concrete charges;

Fig. 7 1s another vertlcal sectlon showmg the pile tube and its bottom cap driven to a sub strata of rock;

Fig. 8 illustrates the pile driven into rock of a type which it may penetrate; and

Fig. 9 is a further enlarged view, showing in perspective the bottom portion of the pile tube with its cap in place.

Referring to the drawing, there is shown in Fig. 1, a metallic tube or shell 1 placed in position with repsect to pile-driving apparatus 2 tobe driven into theground by a With my improved method of pile construction, I may use pile driving apparatus of considerably smaller size, as shown in Fig. 1, whereas when a plunger or Spud 7 is employed much enlarged pile-driving apparatus is necessitated. v Y

Not only does the improved method disclosed herein make it possible to use less ex- -pensive pile-driving apparatus, but a correspondingly advantageous saving in the employment 'of labor is effected. With the avoidance of the use of a plunger or spud for driving the shell 1 there is also an accompanying saving of time.

An enlarged view, principally in section, of the pile shell 1, as it is positioned for entry in the ground, is shown in Fig. 2, wherein the flat bottomed ca 5 is in place 011 the bottom' 0f the shell 1, t 1e impact ring 6 surmounts the top of the shell `and the hammer 3 is about to strike a blow. The repeated blows of the hammer force the shell 1 into the ground, and displace the earth. v

The fiat bottomed cap 4 .prevents entry of the earth into the interior of the shell 1, and, at the same time, due to its shape accumulates earth on its underside. With the down- Ward movement of the pile shell 1, the adjacent earth partly moves laterally away from the shell and relatively upward thereto, the earth directly beneath the cap 4 becoming 4under compression and reacting against the 'lat under surface of the cap. In consequence, an inverted cone of packed earth forms on the under side of the cap 4, as shown at 8 in Fig. 3, and is that residuum of displaced earth that fails to escape from beneath the erated packed earth cone becomes more solid and serves as a driving point to aid in penetra'ting the earth of less cohesion, which must concrete, either plain or reinforced. It is be displaced for .the reception ,of the pile.

VAfterthe shell has been driven vinto they ground tothe desired vdepth it maybe-filled with suitable foundation material, such as frequently necessaryfto provide enlarged footings for the piles. In such cases a bulb of desired proportions on the lower end of each pile admirably supplies such footing.

It is, therefore, proposed in such cases toy" its bottom cap 4, being drlven to rock which deposit a charge of concrete in the hollow shell 1, after it has been sunk, and to enter the shell'with a plunger or spud 7, as shown in Fig. 4. To do this requires no larger sized pile-driving apparatus.

` raised and dropped, forcing ofi' the bottom cap 4 and expelling the concrete charge from the bottom of the shell 1, as illustrated in Fig. 5. Thereafter, the plunger iswithdrawn and an additional chargeinserted in the shell 1, after which the plunger is re-entered and dropped to expel the last concrete charge. This operationis performed as many times as there are number of charges of concrete required for a bulb of given proportions.

. The bulb 9 is thus formed, the driven-olf cap reenforcing it. The still empty shell is then filled with concrete, resulting in a pile substantially like that shown in Fig. 6.

Inasmuch as subterraneanconditions are unlike in different places, it becomes necessary, in driving piles, to successfully contend with the varying difficulties presented, which has not always been of simple'solution. For example, when the usual heavy cast metal driving point is used on the lower end of a pile tube or shell, and" the pile is driven to rock, only the point at the lower end of the pile bears on the rock, as indicated by dotted lines at 10, in Fig. 7. As previously indicated, the pile, under these conditions, some times has its load value depreciated as much as two-thirds, and in municipalities and other rigidly regulated communities, where the authorities insistently require a generous factor of safety, piles merely having a point bearing on rock must either be used in excessive numbers, adding greatly to the cost, or

the edifice they support must be undesirably limited in size and as toits loads.

In Fig. 7 my improved pile is shown as having been driven to rock, and clearly illustrates how, with its flat-bottomed cap, there is secured to the finished pile its maximum permissible load. Since the flat bottomed cap is relatively thin, any upwardly extending projection of the rock that may be under it will, in conjunction with the heavy hammer blows, deform the cap suficiently to permit a substantially perfect seating of the pile. This will be readily understood in view of the light metal that can The plunger 7 isbe used in making the bottom cap 4, such a cap having been used, in one instance, which was made of material of a thickness less than 1/ 150th of the diameter of the pile shell. Such Ya cap on the lower end of `a pile shell, which was driven by a steam hammer showed 'no sign of rupture. Encountering unyielding rock, however, and being subjected to heavy hammer blows, the thin cap 4 will obviously conform itself to the obstruction, and allowthe ile as an entity to secure an entirely satisfactory seat.

In the case ofthe pile shell 1, fitted with .after which the shell will be driven in the rock, thus to be anchored therein. The empty shell 1 is then filled with concrete.

From the foregoing it is apparent that I have devised a concrete pile and a method of forming it, that, while being simple has improved eli'iciency, and eliminates the cost of excavating the interior of the pile shell after it has been driven. It is equally clear that I have produced a concrete pile that avoids the need for a heavy cast driving point which in turn dispenses with the need of patterns for forming such cast points, saving the eX- pense of them and also the time needed to construct them and to mold the driving points. There stands forth markedly the further advantage of being able to construct the bottom caps for the pile sheels in the lield, in sizes to suit any of varying requirements,

by unskilled labor, and from material substantially universally obtainable.

By means of the invention a construction chamber may be formed, extending to a firm bearing of sufficient area to give high load capacities to the foundation material which is subsequently placed in the chamber. Such a result cannot be obtained with driving points, particularly when the latter are sunk to rock or other hard surfaces on account oi the low bearing value of the points.

Moreover, since the bottom cap is fashioned so as to act as a buckle plate and to generate a natural driving point, and suits itself automatically to subterranean conditions Without special attention of the Workmen, and is subject to an automatic dispensing of itself when a shell is to be driven into rock, it is manifest that in a simple manner, I have produced a pile suitable for very general use, at a low cost, and one possessed of very high etliciency.

While certain preferred embodiments of Vfoundation material in t e shell and expelling them therefrom to drive off and flatten the cap beneath the extended footing formed by the expelled charges of concrete whereby the cap serves as a reinforcement below the footing and filling the shell with foundation material.

- 2. An apparatus for forming concrete iles in the ground comprising only atubular riving form, a detachable, substantiallyat, infrangible metallic penetrating head engaged only by the lower end of said tubular driving form, and means for preventing lateral displacement of said head from thel lower'end of said driving form during the driving thereof.

3. An apparatus for forming concrete piles in the ground comprising only a tubular drivjing form, a substantially fiat infrangible metallic enetrating head of substantially uni'- form t ickness and of greater area than that of the lower end of said driving form detachably engaging and closing said lower end and having means presenting a shoulder operable to prevent lateral displacement of said head from the lower end of said driving form during the driving thereof.

4. An apparatus for forming concrete iles in the ground comprising only a tubular riving form, a substantially flat infrangible metallic penetrating head of substantially uniform thickness detachably engaging and closing the lower end of said driving form and having a flange surrounding said lower end.

5. An apparatus for forming concrete piles in the ground comprising a metallic tubular l drivin form, a substantially flat infrangible metallic penetrating head of greater area than that of said driving form detachably engaging and closing the lower end of said driving form and having a eripheral flange surrounding said lower end).

6. An apparatus for forming concrete piles in the ground comprising a cylindrical driving form, a substantially fiat infrangible metallic penetrating head, of greater area than that of-the lower end of said driving form and of less thickness than the thickness of the hollow driving form having at its lower end f