Resistant Emergency Panel Bridge Galvanized Bailey Bridge 321-Type

Resistant Bailey Emergency Bridge/galvanized Emergency Bailey Bridge

The following conditions need to be met to transform the 321-type Bailey bridge into a two-lane bridge:

- **Structural design**:
- **Use an upper bearing structure**: In order to meet the needs of two-way two-lane roads, an upper bearing structure can be used.
- **The main beam adopts a double-row single-layer unreinforced Bailey beam**: The main beam can adopt a double-row single-layer unreinforced Bailey beam.
- **Bridge deck crossbeam design**: The bridge deck crossbeam adopts I32a I-beams, which are set at a spacing of 0.75 meters. The crossbeam also serves as the connection between the Bailey beam and the crossbeam. [28a-type channel steels are arranged longitudinally side by side on the crossbeam, and 6 mm thick Q235 steel plates are welded on the channel steels (which also serve as the construction template for the bridge deck pavement layer).
- **Bridge deck pavement**: The bridge deck adopts 10 cm thick C40 waterproof concrete as the pavement layer. In order to ensure a good connection between the pavement layer and the bridge deck steel components, M16×60 shear bolts are welded on the steel plate, and the shear bolts are arranged at a spacing of 300 mm×300 mm.
- **Load and stability**:
- **Meet load requirements**: The reconstructed two-lane Bailey bridge must meet the requirements of the corresponding load level, such as car-10, car-15, car-20, crawler-50, trailer-80, etc.
- **Ensure stability**: The pins between the Bailey plates must be inserted properly, the connecting angle steel bolts must be tightened, and the connection between the longitudinal beam and the transverse pad beam must be firm and reliable.
- **Construction conditions**:
- **Construction personnel and equipment**: When manually erecting, there are 30 to 40 workers, and the construction workers must wear safety helmets and safety belts. It is strictly forbidden to work on the shelves after drinking. When hoisting Bailey piers, they should be assembled in layers. It is forbidden to hoist a single set of Baileys to the top at one time. When using a crane to hoist and dismantle Bailey piers, a special person should be assigned to direct the crane. It is strictly forbidden for the crane boom to collide with the Bailey beam and its foundation.
- **Construction site**: When the cantilever push-pull method is used to erect a bridge, there must be an equipment configuration and assembly site on our bank with a length not less than 1.5 times the span of the bridge and a width of 8 to 14 meters. When the terrain is restricted and the assembly and pushing erection method is required, the site length should also be not less than the span of the bridge. The longitudinal slope of the assembly site should not be greater than 3%, and the horizontal direction should be roughly horizontal.
- **Other aspects**:
- **Demarcation and leveling of the bridgehead operation site**: Determine the position of the shore repose angle pile. When the shore slope is steeper (greater than the repose angle), corresponding measures should be taken.
- **Cross-strait conditions**: For a single-span bridge, the horizontal distance between the repose angle piles on both sides should generally be less than 34 meters of the bridge span. The soil at the bridge seats on both sides should be solid. When the soil bearing pressure does not meet the design requirements, the foundation under the bridge seat plate must be expanded or reinforced. The height difference between the two sides should not be greater than 5% of the bridge span.

Specifications:

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CB321(100) Truss Press Limited Table
No.	Lnternal Force	Structure Form
		Not Reinforced Model				Reinforced Model
		SS	DS	TS	DDR	SSR	DSR	TSR	DDR
321(100)	Standard Truss Moment(kN.m)	788.2	1576.4	2246.4	3265.4	1687.5	3375	4809.4	6750
321(100)	Standard Truss Shear (kN)	245.2	490.5	698.9	490.5	245.2	490.5	698.9	490.5
321 (100) Table of geometric characteristics of truss bridge(Half bridge)
Type No.	Geometric Characteristics	Structure Form
		Not Reinforced Model				Reinforced Model
		SS	DS	TS	DDR	SSR	DSR	TSR	DDR
321(100)	Section properties(cm3)	3578.5	7157.1	10735.6	14817.9	7699.1	15398.3	23097.4	30641.7
321(100)	Moment of inertia(cm4)	250497.2	500994.4	751491.6	2148588.8	577434.4	1154868.8	1732303.2	4596255.2

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CB200 Truss Press Limited Table
NO.	Internal Force	Structure Form
		Not Reinforced Model				Reinforced Model
		SS	DS	TS	QS	SSR	DSR	TSR	QSR
200	Standard Truss Moment(kN.m)	1034.3	2027.2	2978.8	3930.3	2165.4	4244.2	6236.4	8228.6
200	Standard Truss Shear (kN)	222.1	435.3	639.6	843.9	222.1	435.3	639.6	843.9
201	High Bending Truss Moment(kN.m)	1593.2	3122.8	4585.5	6054.3	3335.8	6538.2	9607.1	12676.1
202	High Bending Truss Shear(kN)	348	696	1044	1392	348	696	1044	1392
203	Shear Force of Super High Shear Truss(kN)	509.8	999.2	1468.2	1937.2	509.8	999.2	1468.2	1937.2

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CB200 Table of Geometric Characteristics of Truss Bridge(Half Bridge)
Structure	Geometric Characteristics
	Geometric Characteristics	Chord Area(cm2)	Section Properties(cm3)	Moment of Inertia(cm4)
ss	SS	25.48	5437	580174
	SSR	50.96	10875	1160348
DS	DS	50.96	10875	1160348
	DSR1	76.44	16312	1740522
	DSR2	101.92	21750	2320696
TS	TS	76.44	16312	1740522
	TSR2	127.4	27185	2900870
	TSR3	152.88	32625	3481044
QS	QS	101.92	21750	2320696
	QSR3	178.36	38059	4061218
	QSR4	203.84	43500	4641392

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Advantage

Possessing the features of simple structure,
convenient transport, speedy erection
easy disassembling,
heavy loading capacity,
great stability and long fatigue life
being capable of an alternative span, loading capacity