TTF "Mekhstroymost" manufactures to order: bridge inventory structures MIK-S, MIK-P
In modern construction and during the construction and repair of bridges, the construction of piers and berths, as well as during some road work, special inventory structures are used. Most of them were developed in the 80s and 90s of the 20th century to simplify existing auxiliary structures. The goal of the designers was to make the auxiliary elements lighter, stronger and more mobile. These tasks were realized, and bridge builders received at their disposal several types of new bridge inventory structures (MIS), most of which are still in use today.
Rack-type bridge inventory structures
Rack-mounted MICs are towers made of steel pipes, fastened together by transverse pipes. The shape of the pipe was not chosen by chance. It is able to withstand significant vertical loads. The MIK-S tower is shaped like a cube, with a side of 2 meters. Each tower is a separate module that can withstand a load of up to 20 tons. Arrays of almost any size can be assembled from modules of rack-mounted bridge inventory structures. Such modularity comes to the rescue when constructing bridges with a large weight, as well as with a significant height. The pipes are fastened together with high-strength bolts. The undoubted advantage of this design is the ease and speed of assembly, which does not require special qualifications of assemblers.
Batch-type bridge inventory structures
MIC package type, or MIK-P, are a horizontal type of auxiliary structures, in contrast to rack-mount elements. Welded I-beams used in the production of these elements are assembled into a package with different lengths from 8000 to 24000 mm. I-beams are connected between longitudinal braces and spacers. Fastening is carried out using high-strength bolts with a diameter of 24 mm. The used grade of low-alloy steel 15HSND gives special strength to packaged bridge inventory structures. MIK-P are also widely used: in addition to the construction and reconstruction of bridges, they are used as crane trestles, unloading structures, as well as the construction of temporary road and railway bridges and covering gaps during road repairs.
Package and rack-mount structures can be used either separately or together. In this case, the elements of MIK-P are based on MIK-S. To protect against corrosion, MIK-S pipes are equipped with special plugs for protection against corrosion. MIK-P can be hot-dip galvanized or painted with durable paints. Because of their reliability and ease of assembly, bridge inventory structures will always have a special place in bridge construction.
| № | product name |
Weightpcs/kg |
Product type |
| 1 | Rack L1 | 1/251 |  |
| 2 | Rack LU1 | 1/236 |  |
| 3 | Stand L2 | 1/140 |  |
| 4 | Rack LU2 | 1/132 | .png) |
| 5 | Brace L5 | 1/30 |  |
| 6 | Spacer L6 | 1/22 |  |
| 7 | L7 brace | 1/103 |  |
| 8 | Brace LU7 | 1/200 |  |
| 9 | L8 brace | 1/103 |  |
| 10 | LU8 brace | 1/169 |  |
| 11 | L9 brace | 1/170 |  |
| 12 | Brace LU9 | 1/273 |  |
| 13 | Grillage L11 | 1/1975 |  |
| 14 | Plank L10 | 1/2 |  |
Nevsky Metalwork Plant produces and supplies packaged bridge inventory structures MIK-P for use in auxiliary structures of various types together with or without MIK-S rack-mount structures. MIK-P made from low alloy steel 15HSND(guaranteed impact strength at -40С and after mechanical aging).
Areas of use
- crane trestles;
- piers, moorings;
- scaffold;
- working bridges;
- unloading structures;
- supporting structures for sliding spans;
- distribution structures on floating/rolling supports;
- covering spans of temporary railway and road bridges;
- covering gaps over culverts;
- restoration work.
MIK-P structures after painting.Use of MIK-P in bridge construction
terms of Use
MIK-P are designed for use in climatic region I in accordance with the standard GOST 16350-80. Temperature environment up to - 60°С.
Corrosion protection
The surface of structures is subjected to anti-corrosion treatment/painted as agreed with the Customer.
Kit contents
The set of package design elements includes 19 brands:
- 4 brands of load-bearing beams (P-4a and P-4, P-3a and P-3);
- 6 grades of longitudinal connections (P-18÷P-23);
- 4 brands of spacers (P-12, P-11, P-16, P-14);
- 3 brands of linings (P-35; P-34 and P-30;);
- 1 grade of stiffener (P-32)
- 1 type of bolt (P-31) ∅ 24 mm.
Installation possible MIK-P on supports of any other structures, incl. tower designs from MIK-S.
Package structures are made from welded I-beams with a length of 8000 and 11920 mm and a height of 1040. Packages of the following lengths are assembled from individual beams: 8000, 11920, 16000 and 19920 mm, as well as 23840 mm.
The elements are connected with high-strength bolts ∅ 24 mm, tightened with a standard wrench with a tightening torque of 20-30 kgf.m, without tension control and without additional processing of the contact surfaces.
Half-diaphragms consisting of horizontal and vertical ribs are welded to the walls of the beams at certain distances. A flange sheet is welded to the ribs.
In grades P-4a and P-3a, the half-diaphragms are welded on both sides, and in grades P-4 and grade P-3 - on one side. Using semi-diaphragms, individual beams are connected into a spatial structure of an unlimited number of beams, which are installed in increments of 550 mm in the transverse direction. The diaphragms are connected using high-strength ∅ 24 mm bolts.
If the beams are installed in increments of greater length in the transverse direction, then a set of inserts of the required width (grades P-12, P-11, P-16, P-14) is placed between the flange sheets of the semi-diaphragms. The beams are also connected by angle longitudinal braces, which are attached to the horizontal gussets of the semi-diaphragms. The gussets have arcuate slots with edges that are outlined along circular arcs with centers aligned with the center of the assembly (the point of intersection of the semi-diaphragm axis with the axis of the beam). This solution to the node allows you to center the diagonal connections at any distance between the beams.
Installation diagrams for packaged span structures, examples:
- under vehicle load;
- under railway load;
- for a crane trestle with a span of 16 meters, under a gantry crane.
Promstroykomplekt LLC manufactures and supplies MIK-S bridge inventory rack structures.
Purpose
Rack-mount bridge inventory structures MIK-S are intended for auxiliary supports, assembly scaffolds, supports for sliding spans, crane trestles, working bridges and other structures. MIK-S can be operated in climatic region I according to GOST 16350–80 at a design temperature of minus 60 °C. To buy rack-mount structures, leave a request for a call back or contact us by phone numbers listed on the website.
Basic technical requirements
The main set of MIK-S consists of 12 brands: 4 brands of racks (L-1 ÷ L-4) 4 and 2 m long, 5 brands of braces and struts (L-5 ÷ L-9), one connecting strip (L-10 ), one all-welded grillage (L-11) and one type of bolt (L-12) with a diameter of 24 mm. Replacement is possible: instead of brands L-1 ÷ L-4 and L-5 ÷ L-9 - brands LU-1, LU-2 and LU-7 ÷ LU-9, all made of pipes 180×9 mm. In total, the MIK-S set includes 10 stamps.
The racks are designed from pipes in accordance with GOST 8731–74 *. At the ends of the racks they are equipped with flanges for connecting to each other and to the grillages and gussets for connecting braces, located in vertical planes passing through the axis of the pipe at an angle of 90° to each other. On one side of the posts, flanges are developed to attach spacers.
At the ends, the spacers and braces have lugs with a hole for one bolt with a diameter of 24 mm and an auxiliary hole for alignment during installation.
The connections of the elements are made using high-strength bolts with a diameter of 24 mm, tightened with a regular wrench with a torque of about 20–30 kgf. m without special treatment of contact surfaces and without tension control.
The L-11 grillage grade consists of welded I-beams and channel connections, combined by welding.
The main element of MIK-S is assembled from the elements of racks, spacers, braces and grillages - a tower of 4 (8) racks with a plan size of 2 × 2 m and a height that is a multiple of 2 m.
Scheme of assembling a grillage from wide-flange rolled steel with a bolted connection (grades L-20 ÷ L-25). As a rule, the grillage is used without disassembly.
Individual towers can be combined with each other in the longitudinal and transverse directions using braces and struts into spatial structures of supports of unlimited size. In this case, the distance between the towers can be 2, 4 and 6 m.
Application area
- Installation scaffolding
- Piers
- Auxiliary support structures
- Working bridges
- Crane supports and other structures