Steel Bridge With Good Quality/steel Structure Bridge Application

Ductility is a critical property in bridge materials, especially when comparing steel to other common materials used in bridge construction such as concrete, composite materials, and wood. Here’s how ductility compares across these materials:

Steel
- **High Ductility**: Steel is known for its high ductility, which allows it to deform significantly under stress without fracturing. This property is crucial for absorbing and redistributing energy from dynamic loads such as wind, earthquakes, and traffic.
- **Fatigue Resistance**: Steel’s ability to deform plastically under cyclic loading makes it highly resistant to fatigue, extending the bridge’s lifespan.
- **Repairability**: Steel components can be easily welded and reshaped, making repairs straightforward and reducing maintenance costs.

Concrete
- **Low Ductility**: Concrete is strong in compression but has low ductility, making it brittle and prone to cracking under tensile stress. This is why concrete bridges often incorporate steel reinforcement (rebar) to enhance their tensile strength.
- **Durability**: Concrete is highly durable and resistant to environmental factors, but its lack of ductility means it requires additional reinforcement to handle dynamic loads.

Composite Materials (e.g., Fiber-Reinforced Polymers - FRP)
- **High Strength-to-Weight Ratio**: Composite materials like FRP offer excellent strength-to-weight ratios and high corrosion resistance, making them ideal for environments prone to corrosion.
- **Low Ductility**: FRP materials generally have lower ductility compared to steel. While they are strong and lightweight, they do not deform as much under stress and can fail more suddenly.

Wood
- **Moderate Ductility**: Wood has moderate ductility and can deform under stress, but it is less durable and more susceptible to environmental degradation compared to steel.
- **Sustainability**: Wood is a renewable resource and can be a sustainable choice for smaller or temporary bridges, but its use is limited by its lower strength and durability.

Comparison Summary
- **Steel** excels in ductility, making it highly suitable for bridges that need to withstand dynamic loads and require flexibility in design.
- **Concrete** is durable and strong in compression but requires reinforcement to handle tensile stress due to its low ductility.
- **Composite materials** offer high strength and corrosion resistance but lack the ductility of steel, making them less suitable for applications where significant deformation is possible.
- **Wood** is a sustainable and moderately ductile material but is less durable and strong compared to steel, limiting its use in larger or permanent bridges.

In summary, steel’s high ductility makes it a superior choice for bridge construction, especially in dynamic environments where flexibility and energy absorption are critical.

Specifications:

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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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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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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