CA1255111A - Trenching method and apparatus - Google Patents
Trenching method and apparatusInfo
- Publication number
- CA1255111A CA1255111A CA000521243A CA521243A CA1255111A CA 1255111 A CA1255111 A CA 1255111A CA 000521243 A CA000521243 A CA 000521243A CA 521243 A CA521243 A CA 521243A CA 1255111 A CA1255111 A CA 1255111A
- Authority
- CA
- Canada
- Prior art keywords
- trench
- trenching apparatus
- chute
- full depth
- trenching
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/18—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels
- E02F3/20—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels with tools that only loosen the material, i.e. mill-type wheels
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/18—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels
- E02F3/188—Dredgers; Soil-shifting machines mechanically-driven with digging wheels turning round an axis, e.g. bucket-type wheels with the axis being horizontal and transverse to the direction of travel
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F5/00—Dredgers or soil-shifting machines for special purposes
- E02F5/02—Dredgers or soil-shifting machines for special purposes for digging trenches or ditches
- E02F5/12—Dredgers or soil-shifting machines for special purposes for digging trenches or ditches with equipment for back-filling trenches or ditches
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Soil Working Implements (AREA)
Abstract
Abstract A Trenching Method and Apparatus A trench, particularly a drainage trench for grassed sports fields and the like, is formed by a two stage method in which the upper half of the trench is excavated by removing soil with a rotary cutting tool, and the lower half of the trench is ploughed to its finished depth without removing soil. Immediately behind the plough there is a delivery chute extending the full depth and width of the trench and has an inclined exit aperture, which delivers material to fill the trench from above-ground hoppers. The chute may be partitioned to form separate upper and lower exit apertures connected with separate hoppers to deliver, for example, gravel to the lower part of the trench and sand above it.
Description
~s~
A Trenching Method and Apparatus The invention relatas to a trenching method and apparatus for forming slit-like drainage trenches in sports ~ields and ths like.
Grassed playing surfaces have to be drained of surface water as rapidly as possible in order to minimise the damage that would inevitably result from their use in a saturated or waterlogged state. Although pitches, fields and parks may be provided with underground drainage systems, because these have to be buried at some depth below the ground surface, there is an inherent tima delay before appreciable quantities of surface water are completely drained away.
In order to speed-up drainage it is known to provide, at intervals in the playing surface, slit trenches filled with sand and other aggregates which can conduct water towards the drainage system more quickly. Clearly, these slit trenches must not introduce any unevenness or irregularity into the playing surface, so that the top of the trench in-fill material has to be flush with the normal surface~ However, if the trenches are excavated by the removal of soil to the full depth of the trench, the filling material tends to compact leaving a surface hollow requiring frequent top-dressing, and if the trenches are formed entirely b~ ploughing there is so much ground heave along the margins of the trench that considerable heavy rolling is needed to level the ground.
The present invention seeks to overcome these disadvantages by providing a method of forming the trenches which does not cause excessive heave along the trench margins and in which subsequent subsidence of the trench filling material does no-t occur. The , . ~ , .
,.:. ' .
-,. :, ~ ',; . :
~ss~
invention also provides apparatus ~or carrying out the method.
According -~o the inv~ntion there is provided a method of forming a trench comprising -the steps of partially excavating the trench by the removal of mat0rial to part only of the desired full depth and ploughing the trench for the remainder of its full depth. Preferably, the step of partial excavation is carried out by means of a rotating cutting tool.
The invention also provides a trenching apparatus for performing the method of forming a trench, the apparatus comprising a carriage having mounted thereon first means for partially excavating a trench to part only of its desire full depth and second means for ploughing the trench to the remainder of its final depth. Preferably, the first means comprises a rotating cutting tool or excavator.
Preferably the apparatus further aomprises means for delivering granular material to fill the trench, which means may include a delivery chute to extend into the trench and having a partition to provide upper and lower delivery apertures which communicate respectively with in~ividual hoppers containing the granular material. In use th0se hoppers may contain different si2ed granular material, e.g. coarse aggregate in one and sand in the other, which can thereby be delivered to different levels in the trench in one operation.
An embodiment of th0 prasent inv0ntion will now be described, by way of example only, with reference to the accompanying drawing.
~' ,~
~L2S~
Referring now to the drawing -the -trenching apparatus comprises a carriage or rigid supporting frams 1 which i5 adapted to be towed behind a tractor vehicle (not shown). Mounted in a vertical supporting sleeve in the carriage 1 is a plough 2 which is rigidly secured to the frame 1 by means of mounting bolts 3.
A rotary cutting tool 4 is carried ahead of the plough 2.
This rotary tool 4 comprisas a rotatable disc 5 around the periphery of which are mounted a plurality of cutting teeth or heads, such as 6. The disc 5 is rotatably mounted in a sub-frame 7 vertically adjustable relative to the carriage by substantially axial movement of a tie rod 8 connected to an operating lever on the tractor, a well known arrangement. The tool 4 may thus be raised and lowered to cuttingly engage the ground by movement of the lever, the depth of excavation may be varied to suit ground conditions and the tool 4 may be raised completely if an underground obstruction is encountered and damages to the cutting head is to be avoided.
The carriage 1 is also provided with a similar vertically adjustable arrangement, generally indicated at 9, which may be operated by a second tie rod lO so that the carrlage 1 may be raised and lowered with respect to the -tractor vehicle to set the depth of the plough 2.
Attached to the rear of the carriage 1 is an hopper axrangement, ganerally indicated a-t 11 comprising one or more hopper compartments. The or each compartment has vertical end walls and flat sides which taper inwardly towards the bottom -to meet a rectangular exit ori~ice ~eeding directly into a . ~."....
:
` '.. ~. ` ' :
~25~
delivery chute 12.
The or each delivery chute 12 comprises two parallel sides as a-t 13 which extend vertically at their forward edges to the full depth of the plough 2. The forward ~ertiaal side of the chute is closed by a member 15, which may be L shaped or joined to a short horizontal member at the bottom to form a partially closed ~ottom wall 16 between the parallel sides. The remaining lengths of the lower edges 1~ of the sides of the chute 12 are inclined upwardly towards the rear of the hopper ll to form a rectangular lower delivery aperture 16 through which material contained in th~ hopper is delivered. In use, the carriage 1 is generally lowered so that the delivery chute extends to the full depth of the trench and substantially fills the width of the trench, then as the apparatus moves forward, material flows from the chute to fill the whole of the trench. Lower ~orward regi~ns of the sides 13 and 14 may be rein~orced by ribs to mitigate against excessive wear of the chute side plates as the chute is pulled through the trench.
The hopper arrangement 11, as illustrated, comprises a single hoppar having a vertical partition 19 which divides the hopper into two compartments roughly equal in volume and which extends downwardly into the delivery chute 12, so that towards the lower edge thersof, the partition also divides the delivery aperture 17 into upper and lower delivery apertures 17A and 17B
respectively.
The hopper may be mounted on the carriage 1 by means of a support 20 attached to the carriage 1 through a vibratable mounting 21. The vibrator contained within the mounting 21 is operative to vibrate the hopper transversely, that is from side to side with respect to the direction of travel of the apparatus. Thus, in us~, -the hopper may b~ vibrat~d in order to promote smoo-th flow of material from the hopper through the delivery chute 12 into th~ trench. The effect of the vibrator 21 is also to transversely vibrate the plough 2 with respect to the dir~ction in which the slit trench is being formed.
In the embodiment describad all power for the trenching apparatus is provided from the tractor vehicle, which is a normal agricultural tractor. The vibrator mechanism is driven by a conventional power drive from the tractor, for example, by a shaft coupling (not shown). The rotary cutting tool is driven by a hydraulic motor, mounted on the trenching apparatus but powered by hydraulic fluid pressure from an hydrauli~ pump on the tractor.
In operation of the trenching apparatus the carriage 1 is mounted behind a tractor vehicle (not shown) and towed in the direction of formation of a drainage slit trench. The rotary cutting tool 4 is lowered to engage th~ ground to the required depth and when rotated is efective to excavate, by removal of soil, the upper part of a trench to the width of the cutting heads. The plough 2 is set to the full depth of the trench, that is it is set to plough to a depth substantially greater than excavated by the rotary tool 4. The delivery chute 12, immediately behind the plough 2, extends to substantially the full depth of the slit trench with its delivery aperture 17 facing rearwardly so that material contained in the hoppsrs is delivered to fill-in the trench as the trenching apparatus is moved forward by the tractor vehicle.
It is preferred in use to fill the forward section of -the partitioned hopper with a coarsa aggregate material such as gravel, and to fill the rearward , ' '~''' ~5~
portion with sand. Thsrefore as the apparatus moves forward -the ploughed lower par-t of a trench is filled with -the coarse ma-terial and the excavated upper part with sand.
According to the method of using the apparatus described above a trench is formed in two stages the first being to excavate the upper part of a trench by the removal of material with a rotary cutter, and in the second part to plough the trench to its full depth~ Preferably the filling material is deposited immediately after the trench is cut. A typical drainage trench has a full depth of approximately 12 inches, or 30 cms and a width of approximately 2 inches or 6 cms. As previously mentioned the delivery aperture 17 of the chute is divided into two approximat21y equal upper and lower apertures 17A and 17B so that the lower half of the trench is filled with coarse material and the upper half is filled with sand to ground level.
It is found in practice that by removing material from approximately the top half of a trench and ploughing without excavating only the lower half of the trench, ground heave along the margins of the trench is minimised and normal ground level can be readily restored with only light rolling. Also, it is found that by ploughing the lower half of the trench and immediately filling with coarse material and sand, subsequent settling of the trench filling material is virtually eliminated so that little or no top dressing is later reguired. Grass is able to grow through the through the top layer of the sand withou-t difficulty so that within a relatively short period the normal surface is fully restored.
~ .
`'~
A Trenching Method and Apparatus The invention relatas to a trenching method and apparatus for forming slit-like drainage trenches in sports ~ields and ths like.
Grassed playing surfaces have to be drained of surface water as rapidly as possible in order to minimise the damage that would inevitably result from their use in a saturated or waterlogged state. Although pitches, fields and parks may be provided with underground drainage systems, because these have to be buried at some depth below the ground surface, there is an inherent tima delay before appreciable quantities of surface water are completely drained away.
In order to speed-up drainage it is known to provide, at intervals in the playing surface, slit trenches filled with sand and other aggregates which can conduct water towards the drainage system more quickly. Clearly, these slit trenches must not introduce any unevenness or irregularity into the playing surface, so that the top of the trench in-fill material has to be flush with the normal surface~ However, if the trenches are excavated by the removal of soil to the full depth of the trench, the filling material tends to compact leaving a surface hollow requiring frequent top-dressing, and if the trenches are formed entirely b~ ploughing there is so much ground heave along the margins of the trench that considerable heavy rolling is needed to level the ground.
The present invention seeks to overcome these disadvantages by providing a method of forming the trenches which does not cause excessive heave along the trench margins and in which subsequent subsidence of the trench filling material does no-t occur. The , . ~ , .
,.:. ' .
-,. :, ~ ',; . :
~ss~
invention also provides apparatus ~or carrying out the method.
According -~o the inv~ntion there is provided a method of forming a trench comprising -the steps of partially excavating the trench by the removal of mat0rial to part only of the desired full depth and ploughing the trench for the remainder of its full depth. Preferably, the step of partial excavation is carried out by means of a rotating cutting tool.
The invention also provides a trenching apparatus for performing the method of forming a trench, the apparatus comprising a carriage having mounted thereon first means for partially excavating a trench to part only of its desire full depth and second means for ploughing the trench to the remainder of its final depth. Preferably, the first means comprises a rotating cutting tool or excavator.
Preferably the apparatus further aomprises means for delivering granular material to fill the trench, which means may include a delivery chute to extend into the trench and having a partition to provide upper and lower delivery apertures which communicate respectively with in~ividual hoppers containing the granular material. In use th0se hoppers may contain different si2ed granular material, e.g. coarse aggregate in one and sand in the other, which can thereby be delivered to different levels in the trench in one operation.
An embodiment of th0 prasent inv0ntion will now be described, by way of example only, with reference to the accompanying drawing.
~' ,~
~L2S~
Referring now to the drawing -the -trenching apparatus comprises a carriage or rigid supporting frams 1 which i5 adapted to be towed behind a tractor vehicle (not shown). Mounted in a vertical supporting sleeve in the carriage 1 is a plough 2 which is rigidly secured to the frame 1 by means of mounting bolts 3.
A rotary cutting tool 4 is carried ahead of the plough 2.
This rotary tool 4 comprisas a rotatable disc 5 around the periphery of which are mounted a plurality of cutting teeth or heads, such as 6. The disc 5 is rotatably mounted in a sub-frame 7 vertically adjustable relative to the carriage by substantially axial movement of a tie rod 8 connected to an operating lever on the tractor, a well known arrangement. The tool 4 may thus be raised and lowered to cuttingly engage the ground by movement of the lever, the depth of excavation may be varied to suit ground conditions and the tool 4 may be raised completely if an underground obstruction is encountered and damages to the cutting head is to be avoided.
The carriage 1 is also provided with a similar vertically adjustable arrangement, generally indicated at 9, which may be operated by a second tie rod lO so that the carrlage 1 may be raised and lowered with respect to the -tractor vehicle to set the depth of the plough 2.
Attached to the rear of the carriage 1 is an hopper axrangement, ganerally indicated a-t 11 comprising one or more hopper compartments. The or each compartment has vertical end walls and flat sides which taper inwardly towards the bottom -to meet a rectangular exit ori~ice ~eeding directly into a . ~."....
:
` '.. ~. ` ' :
~25~
delivery chute 12.
The or each delivery chute 12 comprises two parallel sides as a-t 13 which extend vertically at their forward edges to the full depth of the plough 2. The forward ~ertiaal side of the chute is closed by a member 15, which may be L shaped or joined to a short horizontal member at the bottom to form a partially closed ~ottom wall 16 between the parallel sides. The remaining lengths of the lower edges 1~ of the sides of the chute 12 are inclined upwardly towards the rear of the hopper ll to form a rectangular lower delivery aperture 16 through which material contained in th~ hopper is delivered. In use, the carriage 1 is generally lowered so that the delivery chute extends to the full depth of the trench and substantially fills the width of the trench, then as the apparatus moves forward, material flows from the chute to fill the whole of the trench. Lower ~orward regi~ns of the sides 13 and 14 may be rein~orced by ribs to mitigate against excessive wear of the chute side plates as the chute is pulled through the trench.
The hopper arrangement 11, as illustrated, comprises a single hoppar having a vertical partition 19 which divides the hopper into two compartments roughly equal in volume and which extends downwardly into the delivery chute 12, so that towards the lower edge thersof, the partition also divides the delivery aperture 17 into upper and lower delivery apertures 17A and 17B
respectively.
The hopper may be mounted on the carriage 1 by means of a support 20 attached to the carriage 1 through a vibratable mounting 21. The vibrator contained within the mounting 21 is operative to vibrate the hopper transversely, that is from side to side with respect to the direction of travel of the apparatus. Thus, in us~, -the hopper may b~ vibrat~d in order to promote smoo-th flow of material from the hopper through the delivery chute 12 into th~ trench. The effect of the vibrator 21 is also to transversely vibrate the plough 2 with respect to the dir~ction in which the slit trench is being formed.
In the embodiment describad all power for the trenching apparatus is provided from the tractor vehicle, which is a normal agricultural tractor. The vibrator mechanism is driven by a conventional power drive from the tractor, for example, by a shaft coupling (not shown). The rotary cutting tool is driven by a hydraulic motor, mounted on the trenching apparatus but powered by hydraulic fluid pressure from an hydrauli~ pump on the tractor.
In operation of the trenching apparatus the carriage 1 is mounted behind a tractor vehicle (not shown) and towed in the direction of formation of a drainage slit trench. The rotary cutting tool 4 is lowered to engage th~ ground to the required depth and when rotated is efective to excavate, by removal of soil, the upper part of a trench to the width of the cutting heads. The plough 2 is set to the full depth of the trench, that is it is set to plough to a depth substantially greater than excavated by the rotary tool 4. The delivery chute 12, immediately behind the plough 2, extends to substantially the full depth of the slit trench with its delivery aperture 17 facing rearwardly so that material contained in the hoppsrs is delivered to fill-in the trench as the trenching apparatus is moved forward by the tractor vehicle.
It is preferred in use to fill the forward section of -the partitioned hopper with a coarsa aggregate material such as gravel, and to fill the rearward , ' '~''' ~5~
portion with sand. Thsrefore as the apparatus moves forward -the ploughed lower par-t of a trench is filled with -the coarse ma-terial and the excavated upper part with sand.
According to the method of using the apparatus described above a trench is formed in two stages the first being to excavate the upper part of a trench by the removal of material with a rotary cutter, and in the second part to plough the trench to its full depth~ Preferably the filling material is deposited immediately after the trench is cut. A typical drainage trench has a full depth of approximately 12 inches, or 30 cms and a width of approximately 2 inches or 6 cms. As previously mentioned the delivery aperture 17 of the chute is divided into two approximat21y equal upper and lower apertures 17A and 17B so that the lower half of the trench is filled with coarse material and the upper half is filled with sand to ground level.
It is found in practice that by removing material from approximately the top half of a trench and ploughing without excavating only the lower half of the trench, ground heave along the margins of the trench is minimised and normal ground level can be readily restored with only light rolling. Also, it is found that by ploughing the lower half of the trench and immediately filling with coarse material and sand, subsequent settling of the trench filling material is virtually eliminated so that little or no top dressing is later reguired. Grass is able to grow through the through the top layer of the sand withou-t difficulty so that within a relatively short period the normal surface is fully restored.
~ .
`'~
Claims (11)
1. A method of forming a trench comprising the steps of partially excavating the trench by the removal of material to part only of the desired full depth and ploughing the trench for the remainder of its full depth.
2. A method according to Claim 1, wherein the step of partial excavation is carried out using a rotating cutting tool.
3. A trenching apparatus for forming a trench comprising a carriage having mounted thereon first means for partially excavating a trench to part only of its desired full depth and second means for ploughing the trench to the remainder of its full depth.
4. Trenching apparatus according to Claim 3, wherein the first means comprises a rotating cutting tool or excavator.
5. Trenching apparatus according to Claim 3 and further comprising means for delivering granular material to fill the trench.
6. Trenching apparatus according to Claim 5, wherein said means for delivering granular material includes a chute extending into the trench and having an open lower end for delivery of the material.
7. Trenching apparatus according to Claim 6, wherein the open lower end of the chute has a delivery aperture facing rearwardly with respect to the intended direction of forward travel of the apparatus or the ground, this aperture being inclined upwardly towards the rear.
8. Trenching apparatus according to Claim 7, wherein the chute is partitioned to provide upper and lower delivery apertures.
9. Trenching apparatus according to claim 6 and further including vibrator means effective in use laterally to vibrate at least the chute.
10. Trenching apparatus according to Claim 3, wherein the carriage is adapted to be trailed by a powered tractor vehicle.
11. Trenching apparatus according to Claim 10, wherein the carriage is further adapted to receive a power drive from the tractor vehicle to drive, in use, at least the excavating means.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08413325A GB2159192B (en) | 1984-05-24 | 1984-05-24 | A trenching method and apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1255111A true CA1255111A (en) | 1989-06-06 |
Family
ID=10561464
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000521243A Expired CA1255111A (en) | 1984-05-24 | 1986-10-23 | Trenching method and apparatus |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU585549B2 (en) |
| CA (1) | CA1255111A (en) |
| GB (1) | GB2159192B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2203465A (en) * | 1987-04-15 | 1988-10-19 | Palmer J | Trencher |
| GB2391032B (en) * | 1999-10-06 | 2004-03-31 | Unit Shoji Ltd Yk | Device and method for excavating underdrainage |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB766439A (en) * | 1953-10-26 | 1957-01-23 | Andrew Mcbain | Improvements in and relating to earth-excavating apparatus |
| LU52359A1 (en) * | 1965-11-16 | 1967-01-16 | ||
| GB1226958A (en) * | 1967-08-15 | 1971-03-31 | ||
| GB1383089A (en) * | 1972-08-15 | 1975-02-05 | Hollandsche Aaneming Mij Nv | Suction dredger |
| IE51156B1 (en) * | 1981-08-05 | 1986-10-15 | Mathews Raymond W | Turf cutting machine |
-
1984
- 1984-05-24 GB GB08413325A patent/GB2159192B/en not_active Expired
-
1985
- 1985-11-14 AU AU49902/85A patent/AU585549B2/en not_active Ceased
-
1986
- 1986-10-23 CA CA000521243A patent/CA1255111A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| AU4990285A (en) | 1987-05-21 |
| GB2159192A (en) | 1985-11-27 |
| GB8413325D0 (en) | 1984-06-27 |
| GB2159192B (en) | 1987-09-16 |
| AU585549B2 (en) | 1989-06-22 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |