US2844005A

US2844005A - Jetty installation

Info

Publication number: US2844005A
Application number: US496534A
Authority: US
Inventors: George W Rehfeld
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-03-24
Filing date: 1955-03-24
Publication date: 1958-07-22
Anticipated expiration: 1975-07-22

Description

July 22, 1958 e. w. REHFELD 2,844,005

JETTY INSTALLATION Filed March 24, 1955 2 Sheets-Sheet 1 IN V EN TOR.

6e0rge 14 Rehfe/d W M 14 TTORNEYS.

July 22, 1958 G. w.- REHFELD 2,844,005

JETTY INSTALLATION Filed March 24, 1955 h 2 Sheets-Sheet 2 IN V EN TOR;

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A TTORNEVS.

United States Patent This invention relates to jetties for building up and protecting the banks of streams from erosion. For instance, it is the practice to install lines of jetties along the bank of a stream, where erosion occurs 'or where new banks are to be established. The jetties, whichare contained in the stream and those within flood waters, retard the flow sufficiently for the debris, which is-carried by the current, to settle and deposit around the individual jetties, but the jetties to be efiective must rest upon the ground or bank of the stream, which they protect. When the jetties do not maintain ground contact, erosion starts thereunder and any silt that settles from the water is carried away by the underflow and soon large cavities are formed under the jetties. This condition occurs most readily where the bank merges into the bottom of the stream because the jetties are prevented from settling due to their support by the main anchoring lines. When the underwash becomes extended, the load of the jetties on the main lines, in addition to the added strain produced by the current and pressure of the driftwood thereon, may cause the lines to part and the jetties are lost .or shifted out of position by the current. I

The principal object of the present invention is to provide an arrangement of jetties and anchorage therefor, which leaves the jetties, which are most subject to underflow, free to settle and maintain contact with the ground. If there should be any tendency to underwash, the jetties settle therewith and retard the flow so that silt and debris settling from above can fill around the legs of the jetties to thereby reverse the procedure and build up the bank of the stream.

In accomplishing these and other objects of the invention, hereinafter pointed out, I have provided improved structure, the preferred form of which is illustrated in the accompanying drawings wherein:

Fig. 1 is a cross-section through the bank of a stream,

illustrating a jetty installation, embodying the features of the present invention.

Fig. 2 is a plan view.

Fig. 3 is a cross-section similar to Fig. 1, but showing a portion of the jetties shifted into position for stopping erosion and filling in thereof to build up the bank of the stream.

Fig. 4 is a perspective view of one of the preferred type of jetty units.

Fig. 5 is an enlarged fragmentary perspective view of the jetty illustrated in Fig. 4, showing the connection of the members composing the jetties.

Referring more in detail to the drawings:

1 designates the bank of a stream 2, wherein the current indicated by the arrows 3 tends to erode the bank 1 to ultimately change the course of the stream. Such erosion often occurs upstream from the site of a bridge or other place where it is most important to maintain the original course of the stream, through protection of the bank in a manner to stop erosion and 2 build up the bank for diverting the stream into its regular course. This is accomplished, in accordance with the present invention, by a system of jetties 4. The jetties 4 reduce the velocity of the current, causing debris carried thereby to settle and build up the bank for diverting the current in the desired direction.

In carrying out the present invention, lines of jetties 5, 7, 8, 9 and 10 are arranged somewhat transversely of the bank 1 of the stream 2 and spaced apart to cover the area subject to erosion. Each line of jetties is composed of a plurality of individualjetties 11 that are connected together by lines 12 such as acable or'ser'ieso'f intercoupled rods.

While the invention can be carried out with jetties of various types, best results are obtainedby jetties of the type illustrated in Patent Number 2,669,844, issued to me February 23, 1954. Jetties of this type include

angle iron members

13, 14, and 15 arranged in the form of a tripod, with flanges 16 of the respective members in crossing relation and secured together by fastening devices such as bolts 17 as shown in (Fig. 5. The

members

13, 14 and '15 when thus connected provide outwardly diverging legs 18 and upwardly diverging arms19 as shown in Fig. 5. The bolts .17 extendthrough suitable openings 29 that are provided in the flanges 116. T he flanges 16 of the respective jetty members are also provided with apertures 21 spaced apartalong the length thereof for passing a lacing 22 that increases the effectiveness of the jetties in obstructing andretardingjflow of water and forcollecting the debris and silt that settles around the legs 18 of the jetties.

When the lines 12 aremade .up of rods, the ends of the rods 23am connected bysuitableclamps and the Qjetties are .connected therewith at ,the.,crossing points of the

members

13, 14 and 15. The connections being ,made by passing the line 12along-one side of a jetty and securing it thereto by a section of ,rod .24 at .theopposite side withthe ends of the ,section25 clamped to. or twisted around the line 12 as shown at 26 and '27 in Fig. 4.

A sufficient number of jetties are applied to each line 12 to extend from the bottom of the stream upwardly and over the bank 1 to a distance preferably for covering the extent of overflow during flood periods as shown in Fig. 1. The land end 28 of each of the lines 12 is connected to a deadman 29 or other suitable anchorage preferably located in a convenient position for forming a solid anchorage where it is not subject to erosion during times of high water. The line 12 for the first jetties 5 up stream has an extension 30 that crosses all the other lines at points substantially in alignment with the bank and the extension is secured to the nearest jetty in the respective lines in the manner of the lines 12 as shown in Fig. 4, to leave the stream ends 31 of the lines of jetties 7, 8, 9 and 10 substantially free to move.

In this way, the cable for the line of jetties 5 and its extensions acts as a main line cooperating with the deadmen 29 in maintaining a spaced relation of the transverse lines of jetties 5, 7, 8, 9 and 10 and to prevent swinging thereof about the deadrnenZ? during times of high water. The movable ends or sections 31 of the jetties are free to swing about the connections with the extension or main line and to move downwardly so as to adjust themselves to the slope of the band and bottom of the stream and to permit settling thereof in case the stream should tend to underwash the jetties as shown in Fig. 3. Since the section of jetties 31 are free to move, they settle with any erosion that might take place so as to stop the erosion and retain the silt and other debris that settles because of retardation of the water.

When installing the jetties in accordance with the present invention, the deadmen 29 are suitably located and the lines 11 are connected therewith, after which'the jetties are'erected, laced and attached along the lines 12 as above described and shown in Fig. 4. The lines of jetties are then moved into position with the end sections 31 thereof extending down the bank and into the Water to rest upon the bottomof the stream at the points where erosion is most apt to occur. The extension 30 is extended across the transverse lines 12 for connection with one of the jetties in each of the respective lines 7, 8, 9 and 10 as shown in Fig. 2 so as to substantially and firmly anchor jetties that extend landward of the bank and to leave one ormore freely movable jetties within the Water of the stream or Within the water when high Water occurs. These jetties, being movable, are self-adjusting to the bottom of the stream and prevent erosion, or if erosion should occur, the jetties effect filling in by the silt and other debris carried in the stream.

As above stated, one of more freely movable jetties may be used on each line 12 depending upon the depth and contour of the bank, the number being sufficient to protect the bank at the places where erosion is most likely to start. It is obvious that any number of lines of jetties may be used and that the freely movable sections may be provided on one or more of the lines 12 as the particular installations demand.

From the foregoing, it is obvious that I have provided an improved jetty installation, which reduces erosion and builds up the bank on which the jetties are installed.

What I claim and desire to secure by Letters Patent is:

1. A jetty installation for protecting the bank of a stream from erosion including a plurality of spaced apart parallel lines of jetties extending transversely relatively to'the bank of the stream and having ends remote from the stream and opposite ends in position to be underwashed by water of the stream, anchors connected with said remote ends of the lines of jetties, a tie line extending across the lines of jetties intermediate said ends to provide a substantially fixed section of jetties and a movable end section of jetties in each of said lines of jetties, said movable end sections being adapted to maintain ground contact separately of the fixed sections.

2. A jetty installation for building up and protecting the bank of a stream from erosion, including an anchor line extending transversely relative to the bank of the stream, nonfloating jetties connected with the anchoring line and all adapted for support upon the ground, said anchoring line having an end remote from the stream and an opposite end extending down the bank of the stream, means for anchoring said remote end of the anchoring line, a tie line extending transversely of the anchoring line intermediate said ends to provide a substantially fixed section of jetties for effecting building up of the bank of the stream during times of high water, and a freely movable section of jetties for maintaining ground contact with the bed of the stream and subjected to currents tending to underwash the bank of the stream, said movable section of jetties being adapted to settle and maintain ground contact independently of the fixed section of jetties to stop any underwashing action of the current of said stream.

3. A jetty installation for building up the ground alongside a stream wherein the current of the stream'tends to underwash the ground to be built up, said jetty installation including spaced apart substantially parallel anchoring lines, nonfloating jetties spaced along the lines and arranged to rest upon said ground, means connecting the jetties to the lines for maintaining spaced apart relation of the jetties, an anchor securing one end of each parallel line remotely of the stream, a tie line interconnecting the parallel anchoring lines substantially alongside said stream to cooperate with the anchors in maintaining fixed relationship of the jetties upon the ground to be built up, said jetties on the stream side of said tie line at free ends of the anchoring lines being freely movable on the ground at the points subject to underwash and adapted to settle independently of the relatively fixed jetties to stop any underwashing action of the stream.

References Cited in the file of this patent UNITED STATES PATENTS 780,437 Neale Jan. 17, 1905 1,662,578 Kellner Mar. 13, 1928 2,082,707 Mahon June 1, 1937 2,106,564 Fiske et a1. Jan. 25, 1938