US1607612A - Making concrete foundation piers and the like - Google Patents

Description

C. RJGOW ET Al.

MAKING CONCRETE FOUNDATION PIERs AND THE LIKE Filed May' 11.

Nov. *'23 1926.

Patented Nov. 23, 1.926.

Unita sra'rss PATENT i orrics.

CHARLES B. GOW, OE VEST ROXB'UY, AND LINTON HART, OF BROOKLINE, MASSACHU- SETTS, ASSGNORS T CHARLES R. GO'W' COMPANY. OF BOSTON, MASSACHUSETTS, A

CRPORATIN 0F MASSACHUSETTS.

MAKING CONCRETE FOUNBATION PIER-S AND TEE LIKE.

f Application filed May 11,

This invention relates to the construction or formation of concrete piers or,` columns inV situ for foundations and other purposes,`

and its chief object is to provide an effective and simple method kby which such colums of adequate strength and bearing capacity can be constructed atv low cost through water bearing soil. In carrying shells of successively smaller diameter, one inside of the other; the largest being driven down first, then the second inside ofthe first, the third inside of the second, and so Y on, through the lnon-waterbearing or dry part of the soil. After eachv'shell is driven,

and beforeA the next is sunk, the material en closed by the driven shell is removed, so that a hole isproduced having a temporary lining of steel which eifectually prevents cavh ing or slipping and therefore permits working close to existing foundations without injury thereto. `When the waterbearing layer or stratum is reached or approached as may be known by seepage or by previous sinkings or borings) the sinking of the casing shells ceases and in the lowermost a concrete lining cylinder is established, fitting the shell snugly, and, if desirable or neces` sary, sealed thereto by suitable packing or filling in any convenient manner to exclude water. rThis concrete cylinder, which is left permanently in the ground may be cast in place or it may be cast outside and inserted into the shell at the proper time. In the concrete cylinder an air lock is placed, through which air pressure is applied below the lock to prevent excessive seepage. Excavation is now continued below the lock, and as the shaft ldeepens its sides are covered or lined with wood, metal, or other sheathing suiliciently firm and tight to prevent caving in of thewalls or inow of soft mate` rial. This operation is carried down to the rock or hard bearing material on which the pier is to rest.V While the air pressure is maintained the sheathed portion ofthe hole isfilled with concrete' and the filling carried up intoVA the concrete liningv cylinder far enough to serve as a seal against excessive seepageinto the cylinder from below. As soon as the .concrete is sufficiently hard to make thefseal effective the'airpressureds 1923. Serial No. 638,172.

relieved and the air lock removed. filling is nowcontinued in the openk air, and as the filling proceeds the steel shells are withdrawn from the hole for re-use, the concrete lining cylinder, lion-ever, being left permanently inthe ground.

- The method outlined above is illustrated in various stages in thel accompanying drawings, in which- Y Y Figi is a vertical section showing the shaft-completed down to rock or bearing materiakready for the concrete seal.

Fig, 2 is asimilar section showing the concrete seal in been removed.

Fig. 3 is a vertical section showing the completed pier or column.

F d is a detail verticalsection showing the lower or bearing end ofthe column, provided. with an enlarged footing to distribute,

the load over a larger area of the rocker bearing material. y,

As indicated in 'the drawings, the steel shellslO, 11, l2, of any suitable size and preferably cylindrical in form, are of successively smaller diameter so that one can descend through the other. They are used to provide a temporary lining for the upper part of the hole, being eventually removed as explained hereinafter. rlhe largest shell is first driven or otherwise sunk in the ground, followed by the others in order, the soil in the last driven being removed before the next is sunk. Three such shells are shown, but of course the precise number is immaterial, and depends upon the length of the individual sections or shells 'and the depth at which seepage or inflow becomes or would become excessive. Vhen such point is reached the sinking of the lining shells ceases, and a hollow concrete lining cylinder or caisson 13 is established in the lowermost shell. This caisson or cylinder may be cast outside and inserted into the hole, or it may be cast in place. Preferably it is longer than the shell and is sunk somevdistance below the same, as by 'excavating under it, but in most cases it should project into the shell, so as to prevent excessive seepage orfinflow of water or soft 'material at a later stage ofthe work. lIf lthe caisson, which is to constitute a part of the permanent lining of the-hole, and may contain reinforcing members (not shown )l in its walls, is cast in place removable forms (not shown)- niay be used if'necessary or desirable to make a caisson of the desired length, or, in some cases, it conditions permit, the ground below the lowest shell can be excavated and the bare earth sides of the hole can serve as the outer form or mold below the shell. 1i' necessary or desirable, the caisson may be calked or packed in place in any convenient and suitable manner, not shown. Y

Vv'hen the walls ot the lining caisson are suliiciently hard an air lock, lshown diagrammatically at 14e, is positioned therein, tar enough above the bottom to permit excavation to be carried on under it by any method suited to the existing conditionsf Air is pumped into the air lock andthrough the samefinto the caisson below, and suliicient pressure is maintained to prevent the work being interfered with by excessive seepage;

'As the hole below the caisson is deepened its sides are lined or sheathed 'with' lining members 15, made of wood, metal, or other material. rlfhese members may be segmental in form so as to be arranged end to end circumferentially, and of course are of a' size to permit their introduction through the air lock. Continuingl the excavation and sheathing of the hole, under the necessary air pressure, until rock or hard bearing material 16 'is reached, we then have the stage illustrated in F ig. 1, the hole being lined all the way down to prevent caving or slippage and under suiiicient internal air pressure to prevent undue seepage.

` le now introduce concrete 17, through the air'lock and lill the sheathed portion of the hole, preferably carrying the filling up into the open lower end of the caisson, as indicated in Fig. iar enough to insure against excessive iniow of water 'from below after the air pressure is relieved. 'Vhen the concrete, which serves afterward as the lower portion of the column, has set hard enough to enable it to serve as a seal which will exclude undue seepage, the air lock is removed and the concrete filling is continued to the desired height. As the lilling is carried up, the steel shells 13, 12, etc., are uulled outin advance, one after the other. y e vlowest shell can usually 'be` pulled ybefore or after the caisson 18 is filled, and in some cases "before the' hole vbelow is excavated. In most cases the shell'next above withdrawn as soonas the caisson'is lill'ed, then the hole lett by the -shell withdrawn is filled and-theV work continued in this manner until the filling is Lcompleted'andfithe last shell pulled out. In semesituationsfas Afor example' --whereexeessve lateral` pressures are encountered, it vmay be-necessaryto let the successivelv r fillings set `ly-enough te resist such pressures 'be'orepull-ing the: shell next abe-fe. In 'this l`way" it yie'solnetimes possible to remove all the shells under conditions which'would otherwise make such course dangerous if not impossible.

Below the caisson the sides of the excavation, and. hence the. sides of that portion of: the completed pier, may be substantially parallel, as indicated in Figs. 1, 2 and 3, or they tavernes@ 01';- laSS. Spread O1 0WD- ward iiare, beginning at any desired point. Thus in Fig. Alis shown the lower portion oi' a pier or column with the flare beginning a short distance above the rock 16, terror-1n a belled orenlarged footing by which the total load is distributed over a'larger area and the load per unit area thereby decreased.

It is to be understood that the operations described in the foregoing constitute the preferred practice,'but that the invention can be carried out in other ways without departure from its spirit as defined bythe Jfollowing claims. Y 1 l lalle claim--Y 1. 1n ainethod of forming concrete piers and the like in situ,-sinking into theV ground through each other a series of shells of successivelyl 4less diameter and removing the soil from each shell before the next is sunk, thereby lforming a hole having a temporary lining capable of resisting caving and slippage due to lateral pressure; establishing in the lowest shell a permanent lining section in the form of a hollow concrete caisson and by air pressure therein preventing undue seepage from below; excavating below the permanent lining section to the desired depth and lining the sides of the excavation, while maintaining an air pressure adequate to prevent excessive seepage; depositi-ng concrete in the hole and maintaining the air pressure until the concrete has set firmly enough. to seal the concrete lining section against undue seepage or the like; and thereafter relieving the pressure and filling the concrete lining and the hole above, and withdrawing vthe shells from the ground in succession as the illing proceeds.

Q. n a method of forming concrete piers and the like in situ, sinking in succession, through each other into the ground, a series or removable concentric shells of successively smaller diameter and removing the soil from thev shells as the sinking thereo prbceeds; establishing in the lower shell a hollow liningsection to seal the hold-excavati-ngbelow the caisson to the desired depth andsheathingthe 'sides off-the excavation, and thereafter filling the helewith concrete to-forma pier-ot the desired height, and

withdrawing thelining shells.

Ina Vmeti-ind of--orin-ingconcrete piers and the like in situ, sinking iii-succession, thfreugh each .other-'into the-ground, a series of removable shells-otsuccessively smaller diameter 'and -iemovin-g the soil Y-'therefrom le-ivres@"temrefarlyrlined hele, establishing in the lower shell a hollow caisson to seal the hole and forming a permanent linine' for a part of the hole, extending the hole below the caisson by excavating under air pressure adequate to prevent undue inflow of water, and sheathing the sides of the excavation to maintain the walls thereof; depositing concrete in the hole below the caisson and allowing the concrete to harden under pressure until firm enough to permit the pressure to be relieved; and thereafter continuing the filling in the open air.

l. ln a method of forming concrete piers and the like in situ, sinking into the ground in succession a series of removable shells and reinovii'ig the soil therefrom to form a lined hole, establishing a lining caisson therein, extending the hole below the caisson by excavating below the same under air pressure through an air lock in the caisson while maintaining the walls of the excavation against caving or the like, filling the hole below the caisson with concrete, and when the same has hardened suiiiciently relieving` the air pressure, and thereafter continuing the filling and removing the Yshells in succession as the filling is extended into the shell-lined portion of the hole.

5. ln a method of forming concrete piers and the like in situ, sinking into the ground in succession a. series of removable shells and removing the soil therefrom to form a temporarily lined hole, establishing a hollow concrete caisson therein to serve as a permanent lining for a portion of the hole and applying air pressure through the caisson to exclude excessive inflow of water from below, deepening the hole below the permanently lined portion 'by excavating below the same under said air pressure, and

'scaling the lower end of the caisson with concrete to prevent undue inflow into the saine after the air pressure is relieved.

t3. In a method of forming concrete piers and the like in situ, sinking into the ground a series of shells and removing the soil therefrom, establishing a caisson therein and applying air pressure through the lining caisson to prevent excessive inflow of water from below, deepening thehole below the lining caisson by excavating below the same under said air pressure and lining the deepcned portion to maintain the walls thereof against collapse, filling the said deepened portion of the hole with concrete and sealing therewith the lower end of the lining caisson to prevent undue inflow after the air pressure is relieved, and thereafter filling the hole with concrete in the open air.

7. ln a method of forming concrete piers and the like in situ, forming in the ground a hole having a temporary lining down to a point where further deepening of the hole would cause excessive inflow of water, establishing a lining caisson therein and applying air pressure through the caisson to prevent said excessive inflow, excavating under air pressure below the caisson to deepen the hole and maintaining the walls of the deepened portion against collapse, depositing concrete in said deepened portion and under said air pressure sealing with the concrete the lower end of the caisson to prevent excessive inflow of water after theV air pressure is relieved, and thereafter in the open air filling' the hole with concrete above the seal.

8c ln a method of forming concrete piers and the like in situ, forming a hole in the ground and providing the same with a temporary lining composed of removable lining members, establishing in the lower portion of the temporary lining a permanent lining section of concrete, excavating below the permanent lining section to deepen the hole, sealing the said deepened portion of the hole and the bottom of the permanentlining section with concrete to exclude water, and filling the permanently and temporarily lined portions with concrete and removing the removable lining members from the upper portion of the hole.

In testimony whereof we hereto affix our signatures.

CHARLES R. GOV. LINTON HART.

Images