Prefabricated Steel Bridge For Highway/steel Portable Bridge

A Bailey bridge is a modular, truss-based bridge designed for rapid assembly and disassembly. Its main components are designed to be lightweight, easy to transport, and simple to connect. Here are the key components of a Bailey bridge:

1. **Panel Girders**
Panel girders are the primary structural elements of a Bailey bridge. They are rectangular frames made of steel, typically measuring 10 feet (3.05 meters) in length and 5 feet (1.52 meters) in height. Each panel girder consists of vertical posts and horizontal chords connected by diagonal bracing. These girders are designed to be easily connected to form the main trusses of the bridge.

2. **Transoms**
Transoms are horizontal beams that span between the panel girders. They provide support for the bridge deck and distribute the load evenly across the trusses. Transoms come in various lengths to accommodate different bridge widths and are typically made of steel.

3. **Decking**
The decking is the surface of the bridge that supports vehicles and pedestrians. It is usually made of steel or wooden planks and is laid on top of the transoms. The decking can be designed to support different types of traffic, from light vehicles to heavy military equipment.

4. **Double-Webbed Members**
Double-webbed members are additional structural components used to increase the load-carrying capacity of the bridge. They are essentially two panel girders connected together to form a stronger, double-width truss. These members are used in situations where the bridge needs to support heavier loads.

5. **Single-Webbed Members**
Single-webbed members are individual panel girders used in lighter load applications. They are the basic building blocks of the bridge and can be combined to form the required truss structure.

6. **Bracing**
Bracing components, such as diagonal and vertical bracing, are used to provide additional stability and rigidity to the bridge structure. These components help to distribute loads and prevent deformation under stress.

7. **Bearings and Supports**
Bearings and supports are used at the ends of the bridge to transfer the load to the foundations. These components can be adjustable to accommodate different ground conditions and ensure proper alignment of the bridge.

8. **Accessories**
Accessories such as ramps, parapets, and walkways can be added to the bridge to enhance its functionality and safety. Ramps provide access to the bridge from the ground level, while parapets and walkways ensure the safety of pedestrians and maintenance personnel.

Assembly Process
The assembly of a Bailey bridge involves connecting these components in a specific sequence:
1. **Foundation Preparation**: The site is prepared, and foundations are laid for the bridge supports.
2. **Panel Girder Assembly**: Panel girders are connected end-to-end to form the main trusses.
3. **Transom Installation**: Transoms are placed between the panel girders to create the framework for the deck.
4. **Decking Installation**: Decking is laid on top of the transoms to form the bridge surface.
5. **Bracing and Support**: Bracing components are added to ensure the stability and rigidity of the structure.
6. **Final Adjustments**: Bearings and supports are adjusted to ensure proper load distribution and alignment.

Advantages of Modular Design
The modular design of Bailey bridges allows for rapid assembly and disassembly, making them ideal for temporary or emergency use. The components are lightweight and easy to transport, and they can be adapted to various bridge lengths and load requirements. This flexibility and ease of use have made Bailey bridges a popular choice in military, civil engineering, and disaster relief applications.

In summary, the main components of a Bailey bridge include panel girders, transoms, decking, double-webbed members, single-webbed members, bracing, bearings, and supports. These components are designed to be easily assembled and disassembled, providing a versatile and reliable solution for various bridge construction needs.

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