Soviet Army.
Engineering corps

(Years sixtieth - seventieth)

Pontoon-bridging column PMP  (ПМП)

Pontoon-bridging column PMP is designed to provide bridges and ferries. The complete set of PMP equipment is used to construct 60 ton and 20 ton carrying capacity bridges and 20 ton up to 170 ton carrying capacity ferries. The most frequently used ferries are 40-, 60-, 80- ton floating sections and 130-, 170-ton floating and abutment sections.

PMP construction basic characteristics:
1.Ferries and bridges are constructed as entire floating sections;
2.PBC consists of folding four-pontoon sections ready to be used as parts of the bridge or the ferry;
3.The complete set of PMP equipment may be used either as a bridge or as a ferry;
4.Landing pies are not needed for ferry transportation, the ferry may be fixed on the river bottom while loading and unloading;
5.The folding sections decks serve as a road;
6.Light vehicles may move in both directions.

PMP floating bridges basic characteristics:

PMP ferries basic characteristics:

Pontoon-bridging column PMP is full equipment for bridging through water obstacles . Since1962 the Soviet Army was armed with this type of PMP .

This equipment may be used for as a ferry to carry people and equipment through water obstacles. Besides PMP may include vehicles to transport equipment. The standard set of equipment allows to construct bridges of different length and carrying capacity.
The bridge length may be up to 227 m for 60 ton cargo; or up to 382 m for 20 ton cargo. Permissible current flow is up to 2.5 m/sec. The pontoons upper part is used as a road.
The PMP includes 32 floating sections, 4 abutment sections, 2 road covers, 12 tugboats. The transportation of the sections is performed by 38 KrAZ-255B trucks equipped with special devices.  The boats BMK-90, BMK-130 or BMK-150 are tugged by ZIl-130(ZIL-157) trucks with the help of a trailer or their own wheels . If PBC contains BMK-T boats; they are transported on 12 KrAZ-255B trucks platforms.

The KraZ truck carries one section, which includes two middle and two edge pontoons. The pontoons are connected by hinges. For transportation the section is folded up on the truck platform. The picture displays the truck with a floating section. Next picture is the back view of the truck with the section containing two middle right-angled pontoons and two edge curved pontoons. The abutment section is different from the floating section. Due to its form the abutment section allows to connect the bridge with the bank, besides, the section has folding devices so that cars could go down the bridge to the bank.

The section crew should consist of a driver and two pontooneers. It can also consist of a driver-pontooneer and a pontooneer. The procedure of installing the bridge or a ferry is as follows: the truck moves backward into the water up to the point where the depth is not less than 1 m; then the truck brakes abruptly; the pontooneer releases the hold; the section released rolls down the platform into the water easily.

In the water the section spreads under the influence of floatation powers with the help of hinges. In the picture the section is in the process of spreading (back view). At the moment the section is being hold by a mooring rope from the bank. The other edge of the rope is fixed on the truck. The driver-pontooneer and the pontooneer go up to the deck, lock the bottom and the deck to make the section construction rigid.

In the picture the section is spread (back view). After the deck and bottom are locked the pontooneers bring the sections closer to each other using hooks and lock the sections together. Thus the bridge line is being assembled along the bank. During the procedure the section is hold by mooring ropes fixed on the truck on the bank. As soon as the section is assembled the truck throws the mooring rope and leaves the site. The road width is 6.5 m.

The assembled bridge line is turned around and placed across the river; the abutment sections are fixed at the bridge by mooring ropes. The bridge line is kept by tugboats until anchors are fixed on each section and dropped. After the anchor ropes are stretched and the bridge line is even, the tugboats leave. This is a part of the bridge line in the picture (view from above). The dark green part is the road 6.5 m wide. Such road width allows the tanks to move at 30 km/h and vehicles have no speed limit. Besides the vehicles can move in two columns or in opposite directions along the road simultaneously. This installation scheme makes it possible to construct a bridge 227 m long with carrying capacity 60 ton out of one set of equipment of the previously described type.

The installation scheme is different for 20 ton cargo bridge. The section is disconnected at one side; then the section is turned around at 180 degrees angle. In this case the bridge line looks as follows: the first section is in a usual position - the second section is turned around - the next section is in a usual position - and so on. The road width is 3.3 m, and it’s possible to construct 382 m long bridge out of one set of equipment.

The road cover is a metal coated tape. It consists of detached sections connected with each other by hinges. The tape covers KraZ trucks platforms. The road cover is used to make it possible for the vehicles to get on the bridge from marshy ground.

The notice of the writer. American engineers made a mere copy of our PMP for their army in 1972. The only difference was that they used duralumin instead of steel for pontoons and installed them on American trucks. They even used the same number of bolts on hatches leading inside pontoons.
The Czechoslovak Republic got a license for PMP production, the Czech engineers installed the pontoons on their four-axed trucks Tatra.
The bridge line may consist of as many sections as you wish. It’s possible to make a 430-metres bridge if you use two PBC complete sets of equipment. However it’s expedient to use ferries if the water obstacle is extremely wide.

Bibliography:

1.Инструкция по материальной части и эксплуатации понтонно-мостового парка ПМП . Военное издательство МО СССР. Москва 1966г.
2.Военно-инженерная подготовка. Учебное пособие. Военное издательство Министерства обороны СССР. Москва. 1982г.
3.Понтонно-мостовой парк ПМП. Руководство по материальной части и применению. Военное издательство Москва 1981г.

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