US 2196211 A
Description (OCR text may contain errors)
I April 9, 1940- J. P.- HARTMAN -METHQD AND APPARATUS FOR GROUTING Filed y 28, 1938 Patented Apr. 9, 1940 UNITED STATES PATENT OFFICE 2,196,211 METHOD'YAND APPARATUS FOR GROUTING John P. Hartman, Fort Peck, Mont. Application May 28, 1938, Serial No. 210,782 7 Claims. (01. 61-36) (Granted under the act- 01' March 3, 1883, as
amended April 30, 1928; 370 0. G. 757) This invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.
This invention relates generally to groutin but more particularly to a grouting tool and the method of using the same. 1
One object of the invention is to provide a multiple jet grouting tool adapted to cut through the subsoil with a combined jetting and sawing action.
Another object of the invention is to provide Another object of the invention is to'provide a grouting tool which is of simple, economical and durable construction, and one which may be easily operated and cleaned.
Another object of the invention is to provide a method for hydraulically cutting away the subsoil with a sawing action and forming an impervious curtain in the out area.
A further object of the invention is to provide a method and means for producing a uniform and continuous grouted volume in the locality desired and one which will be impervious to the seepage of water.
The invention which forms the subject matter of this application relates to a method and means of grouting gravels, sands, silts and mixtures thereof, in which the groutingsolution or suspension is introduced under pressure in amanner resulting in the flotation of the material being grouted immediately surrounding the grouting tool.
Certain types of soil are very difiicult to grout, although they are quite pervious for a flow of water. The difiiculty arises whenever themaximum dimension of the pores of the soilis less than the diameter of minimum dimension of the grout particles, as the grout particles cannot penetrate into the pores regardless of the applied pressure unless some action takes place to enlarge the pore openings. In many cases the enlargement of the pores to permit penetration of the grout produces detrimental effects in the original structural conditions of the adjacent property. It is also practically impossible to control the volume to be grouted. V
The flotation process of grouting enlarges the pore space temporarily within definite controllable limits until the grout can penetrate,
after which the setting soil particles trap the grout particles in the soil pore spaces.
The improved method and apparatus for e1- fecting grouting operations may be utilized in the following forms of engineering work:
Grouting of foundations for all types of structures;
Grouting around caissons, cribbings and coffer dams;
Grouting of earth, dams, levees-and dikes; 10
Grouting cores in earth dams, levees and dikes constructed of gravel, sand, silt and mixtures thereof, parallel to the axis of the structures after the complete placement of earth fill;
Grouting of material where it is notnecessary '16 to grout large areas, but merely to form cut-01f curtains.
Referring more particularly to the accompanying drawing in which corresponding parts are indicated by similar reference characters:
Fig. 1 is a front elevation of the grouting saw;
Fig. 2 is a side centrally sectionized elevation of the grouting saw;
Fig. 3 represents a section taken on the line 3-3 of Fig. 2; I Fig. 4 is an enlarged top plan view of one of the nozzles, as illustrated in Fig. 1;
Fig. 5 is an enlarged sectionizedv view of a nozzle, as shown in Fig. 2;
Fig. 6 is a side elevation of a tractor provided ,30 with a reciprocating apparatusv for operating the saw.
The grouting device or saw consists of a pipe 10, composed of metal or other suitable material, pointed at one end and equipped with a series, of nozzles I I extending longitudinally in a straight line throughout its length. The pipe may be circular in shape, although those having oval or streamlined sections, as shown inFig. 3, are preferred. The nozzles I I through which the grout is forced, as will be further described, are formed with a hexagonal head I! adapted to fit a wrench and a slightly tapered and externally threaded body portion I3 adapted to fit threaded holes 1'4 in the pipe.
The nozzles are dimensioned so as to be interchangeable in order to expedite replacement after excessive wear, and also by varying the size of their internal passage I 5, adjustments can be made to adapt the equipment to the type and volume 50 of the grouting material.
A smaller pipe I6 is welded or otherwise fastened to the main pipe 10 throughout its length and diametrically opposite to the longitudinal row of nozzles II. This small pipe 16 is for the u passage of water under pressure, and is used to jet the main grout pipe l0 into the material to be grouted.
The grout consisting of bentonite or other suitable material is pumped into the main grout pipe l0 under pressure and is expelled therefrom through the nozzles I I. By proper spacing of the nozzles and by using sufiicient pressure on the grout, the material immediately in front of the nozzles and some of the material surrounding the grouting pipe is floated, resulting in a uicksand condition.
By employing a mechanism for producing a reciprocating motion, and to which the upper flange ll of the grouting pipe [0 may be attached, such as the mechanism shown on the tractor illustrated in Fig. 6, it is possible to move the grouting pipe or saw vertically as it progresses horizontally through the material to be grouted' in the direction of the nozzlejets, the action being similar to that of sawing. As the horizontal movement progresses, the sand behind the pipe being no longer floated, settles, trapping the grout in the pores of the material. This method of grouting forms definite grouted volumes the sizes of which are functions of the size grouting equipment and the pressures used.
In carrying out the method for grouting with the saw described above a suitable tractor mounted operating mechanism is provided. This mechanism comprises a reciprocating supporting tube [8 slidably mounted in a supporting bracket i9 and connected by a link 28 to an oscillating rocker arm 2!. The rocker arm 2! is pivotally mounted on a shaft 22 which is in turn mounted in two supporting brackets 23, only one of which, is shown. In the illustration shown in Fig. 6, it will be noted that the rocker arm 2!, is provided with a slot 25 which slidably receives the rectangularly projecting pin 26 of the crank arm 21.
The crank arm 21 is connected to a rotating shaft 28 which is operated through gears connected to the tractor motor and which are not shown in the illustration. The motor is adapted to effect a reciprocating motion of supporting tube 18 which is imparted to the saw H] to which it is connected through its lower flange 3i and flange ll of the grouting pipe or saw.
As the tractor moves along the surface of the terrain the pipe or saw it which has been sunk into the subsoil is given a reciprocating motion by the mechanism described above, as bentonite or other suitable grouting material is pumped through the flexible tube 29 and supporting tube 18 into the interior of the grouting pipe or saw I0, and out through the nozzle l I as shown in Fig. 6. The pipe [3, which is attached to the saw i0 is connected to a water supply (not shown) through the flexible tube 311. The pipe it is of great advantage in sinking the saw as described above.
Having described my invention, what I claim as new and wish to secure by Letters Patent is:
1. A grouting saw comprising an ejecting pipe for conveying grouting material provided with a longitudinal row of ejector nozzles, and a longitudinally aligned pipe of smaller diameter for conveying water, arranged diagonally opposite said nozzles and terminating with an outlet opening at the end of said ejecting pipe.
2; In a grouting apparatus the combination with an internally bored grouting tool, means for imparting a vertical and a longitudinal movement to the tool, a source of cementitious material in communication with the bore of the tool, and means for discharging the material from the bore in the form of a plurality of streams.
3. In a grouting apparatus the combination with an internally bored grouting tool, means for imparting a vertical and a longitudinal movement to the tool, a source of cementitious material in communication with the bore of the tool, and means including a series of aligned openings for discharging the material from the bore in the form of a plurality of superimposed streams.
4. In a grouting apparatus the combination with an internally bored grouting tool, means for imparting a vertical and a longitudinal movement to the tool, a source of cementitious material in communication with the bore of the tool, and means in connection with the tool for discharging said material from the bore in the direction of the longitudinal movement of the tool and in the form of a plurality of superimposed streams, said means including a series of vertically spaced nozzles.
5. In a grouting apparatus the combination with a grouting tool including an ejector and an irrigating tube; 01" means for imparting a vertical and a longitudinal movement to said tool, a source of cementitious material in communication with said ejector tube, a source of water supply connected to said irrigating tube, means including a plurality of vertically spaced nozzles for discharging the material from said ejector tube in the form of a plurality of parallel vertically spaced streams and in the direction of the longitudinal movement of the tool, and means for directing a stream of water from the irrigating tube in the direction of its vertical movement.
6. A grouting process for forming a subsoil wall consisting in lineally directing a series of superimposed streams of cementitious material through said subsoil, and simultaneously imparting a vertical movement to said streams.
7. A grouting process for forming a subsoil wall substantially impervious to moisture consisting in irrigating the subsoil with a downwardly directed jet of water and at the same time lineally directing a series of superimposed streams of cementitiousimaterial through the subsoil, while imparting a reciprocatory and a longitudinal movement to said streams.
JOHN P. HARTMAN.