RUSSIAN

The activity of Kombest Co is concerned with the applying of the trenchless technology for laying and reconstructing the municipal engineering communication pipelines and building cast-in-place piles.

High priority of trenchless technologies is obvious due to money saving as compared to the application of conventional trench methods and the elimination of road covering destruction under the conditions of high housing density or large depth of pipe laying.

Trenchless Pipeline Replacement Process

The process developed provides the trenchless replacement of steel, iron or non-metallic worn-out pipelines of 100mm -350mm diameter for plastic pipes of 160mm 400mm diameter. A set of equipment consists of a witch, an anchor, chain wrenches, an instrument set, air-supplying hoses. The procedure is as follows:

A compound expander is mounted on a pneumatic machine, located in an entrance man-hole. An air-supplying hose and the winch cable, passing through a pipe section to be replaced, are connected to a rear or front end of the machine (it depends on peculiarities of the technological process applied). When moving along the pipe the expander destroys it and stamps its fragments info the ground and pulls a new pipe info a hole formed. A new pipe is extended by pipe sections in the entrance man­hole.

See: Equipment kits and technology for rehabilitation of water-supply and canalization systems

Trenchless Pipe Laying Process

The process for piling pipes with open front end provides an opportunity to increase a diameter of a pipe to be laid by a factor of two at the expense of reduction in soil frontal resistance as compared to the puncture process. The soil cork is eliminated in the moving pipe due to the impact load action. Pipes are stuffed with soil along the total length and then the soil is cleaned out with a mobile soil intaking device. A set of equipment consists of a pneumatic impact device for piling pipes, a pneumatic impact device for actuating a soil intaking device, an adapter, guiding frame, a pneumatic winch, a soil intake device (sand pump), air-supplying hoses.

The process developed provides trenchless laying of pipelines of 159mm -1400mm diameter.

Process for the cast-in-place pile construction implies multiple operations of filling a hole sank by a pneumatic punch with the semi-dry concrete mixture and subsequent sinking the filled hole by a pneumatic punch. A pile is formed by pressing in walls of a hole, in doing so a good cohesion of a pile with soil is provided. Both vertical and inclined piles cam be used for stregthening of foundations. And the strengthening of foundations takes place due to soil stabilization and foundation's load on a pile. Depending on the character of load the pile can be reinforced or unreinforced. The outer diameter varies in the range of 150mm-300mm and it depends on the number of punch's passings through a filled hole and on a type of a device used in the process. Maximum length of a pile depends on the soil load, specifications and varies in the range of 6-10mm.

A set of equipment consists of a pneumatic reversible punch, a compressor, a mixer, a tripod with a hand witch or a starting device. Cast-in-place piles are efficient for repairment or strengthening of different constructions, strengthening of slopes, building of supporting walls, building of anchor strengthening, deep compressing of settled or bulk soil.

The new generation of Russian pneumatic impact machines have got quite specific features as compared to foreign annalogues:

• mounting and demounting of working equipment can be carried out directly in a man-hole;
• repairment and replacement of pneumatic impact machines is possible just under working conditions;
• supply of the compressed air (energy carrier) from the front or rear end of the machine.

The Russian and foreign patents for the said technology and equipment sets are available. The commercial production of equipment sets has been launched at Novosibirsk plant "Siblitmash". KOMBEST Co. guarantees the accident-free work of the equipment for 1.5 years.