| WO/2008/062960 | AN ASSEMBLY MANHOLE HAVING S-SHAPED HINGE STRUCTURE |
| WO/1993/018240 | STIFFENING FLANGES AND GUSSETS FOR DEFORMATION RESISTANCE OF MANHOLE COVER SUPPORT |
| WO/1989/004895 | TELESCOPIC WELL OR COLUMN PIPE |
| CLAIMS 1) The method consists of the horizontal and vertical cutting of part of the manhole and its surrounding asphalt in a way that the depth of the cutting to have the same perimetrical height from the leveling of the asphalt. 2) The method consists of the gluing of the new pre-constructed element identical to the inner dimensions of the upper part of the restoring manhole which includes the metal base supporting the cover. 3) The gluing is done with the use of industrial glue, or any other gluing materials, or by the use of coach screws through the old part and the pre-constructed element. 4) The void that is created through the vertical cutting is filled with fast drying cement or any other material appropriate for the immediate stabilization of the pre-constructed element. 5) The horizontal cutting machine is a common drill with a custom axis of 30 cm length and 2 cm perimeter and has been adjusted on a frame base that can be adjusted in height so that the cutting is leveled to the asphalt. It has the ability of a steady cutting in height of the perimetrical movement so that the horizontal cutting is carried out with absolute precision. |
Until today the method being used for the restoration of manholes (drains) that have either been raised or lowered after time of placement, is excavation and replacement of the manhole so that it levels with the asphalt, and it is being stabilized with the use of cement.
The disadvantages of the above mentioned method are the following:
A. It requires extensive use of heavy machinery (excavator) therefore serious noise being produced.
B. During the excavation and the replacement there is high risk of waste material or cement to fall into the manhole causing future malfunction.
C. The time to stabilize the manhole to its new position depends on the time the cement needs to dry out and exceeds 48 hours resulting substantial problems to the traffic.
D. The cost of the restoration is high due to the man-hours that are required.
E. The time needed to give the specific area back to the traffic as well as the cost of the restoration prevents or postpone the immediate restoration resulting extensive damage to the passing vehicles
The new method of manhole (drain) restoration on top of the road either by them being lowered or raised is based on the vertical cutting and removal of part of the cement walls of the manhole along with part of the surrounding asphalt and its replacement with a new one pre-constructed
The cutting is achieved with a cutting disc which moves on top of the frame (FIGURE 1) leveled to the road so that the part being cut to have the same distance as the height of the pre-constructed element which will replace. For the final removal of the horizontal piece that has been cut, a vertical cutting disc is being used which cuts the road that is glued perimetrically to the outer side of the walls of the manhole up to the depth of the horizontal cutting and completely releases the part that has been cut which is then removed. The pre-constructed element with a height of 10-15 cm is placed in its place and is glued to the old part with industrial glue of two ingredients like "Quick permaweld", also the space of the 1-2 cm that has been created from the vertical perimetrical cutting is filled with fast dry cement. The old cover of the manhole is being replaced and within one hour the area can be given back to traffic.
The advantages of the aforementioned method are as follows:
A. The time required for the restoration is reduced to 1-2 hours where the old method needed 5-6 hours.
B. The time required for the area to be given back to traffic is reduced to 2-3 hours where the old method needed 24-30 hours.
C. The old supporting area of the base is being maintained which has already been compressed by the weight of the passing vehicles minimizing the probability of later setback.
D. The cost of the restoration is reduced to 1-2 man-hours compared to 10-12 man-hours of 2 workers.
E. The noise is greatly reduced due to the absence of heavyweight machinery that the old method required.
FIGURE 1 displays the frame of alignment where the cutting mechanism is attached so that it can move perimetrically at the same level.
FIGURE 2 displays the placement of the alignment frame on top of an open manhole. The length of the axis of the disc sets the height of the horizontal cutting and the diameter of the disc sets the depth of the cutting. During the execution of the cutting, the axis of the disc ends up to the inner perimeter of the manhole and acts as a guide for the steady depth of the perimetrical cutting.
FIGURE 3 displays the incision of the part that has been cut which its dimensions are indicative and can change according to the needs of the specific restoration.
A: Manhole Wall B: Asphalt C: Part being cut
FIGURE 4 displays the incision of the placed pre-constructed element which also its dimensions are indicative and can change to 2-3 different standardizations depending on the needs of the different restorations. The gluing material for the pre-constructed element with the old part of the manhole will be industrial glue of two ingredients, and for the rest of the contacting parts, fast drying cement. Furthermore if found necessary, holes can be drilled through the old part to the new element, so that coach screws can be used for greater stability.
A: Pre-constructed element B: Gluing Material