What are the applications of MS series multi-directional displacement comb plate expansion device on
The MS series multi-directional displacement comb plate expansion device, as the core expansion component of highway bridges, has the core advantages of strong multi-directional displacement capacity, excellent bearing performance, good sealing and waterproofing, and long service life. It specifically solves the expansion deformation problems caused by temperature changes, vehicle loads, foundatio
The MS series multi-directional displacement comb plate expansion device, as the core expansion component of highway bridges, has the core advantages of strong multi-directional displacement capacity, excellent bearing performance, good sealing and waterproofing, and long service life. It specifically solves the expansion deformation problems caused by temperature changes, vehicle loads, foundation settlement, etc., while ensuring smooth driving and structural safety. Its specific applications in highway bridges are as follows:
1、 Core application scenario: Adapt to different bridge types and working conditions
1. Large span highway bridges (cable-stayed bridges, suspension bridges, continuous beam bridges)
Application logic: Large span bridges have a large span (usually ≥ 50m), significant expansion and contraction of the beam body during temperature changes (up to 100-400mm), and are greatly impacted by vehicle loads. At the same time, there may be multi-directional displacement requirements such as horizontal, vertical, and corner changes. The MS series comb plate expansion device adopts a "comb cross meshing+multi-directional displacement mechanism" design, which can achieve longitudinal large displacement expansion and is compatible with horizontal and vertical micro displacement, avoiding the expansion device from getting stuck or damaged when the beam body deforms;
Typical value: such as cable-stayed bridges across rivers on highways and continuous beam bridges on urban ring roads, this device can absorb the significant expansion and contraction of the beam due to seasonal temperature differences, while also withstanding the high-frequency impact of heavy trucks (axle load ≥ 130kN), ensuring no jumping sensation on the bridge deck and reducing vibration damage to the bridge structure and vehicles.
2. Small and medium span highway bridges (simply supported beam bridges, slab bridges, arch bridges)
Application logic: Small and medium span bridges (with a span of 5-50m) are the main components of the highway network, with relatively small expansion and contraction (30-150mm), but high requirements for construction convenience, cost-effectiveness, and driving comfort. The MS series products have diverse specifications (suitable for expansion and contraction of 30-200mm), and do not require complex excavation during installation. The comb plate is made of high-strength steel (such as Q355, stainless steel), with strong bearing capacity (single tooth bearing capacity can reach 50kN or more), and the comb clearance is small (usually ≤ 5mm) to avoid tire jamming;
Typical value: such as simply supported beam bridges on urban and rural main roads, and ramp slab bridges on highways. This device can be quickly installed, adapt to standardized bridge construction, and solve the problems of traditional expansion joints (such as modular joints) being prone to jumping and damage, improving highway traffic efficiency and safety.
3. Irregular Bridges (Curved Bridges, Diagonal Bridges, Wide Bridges)
Application logic: Curved bridges, skew bridges (skew angle ≥ 30 °), and wide bridges (deck width ≥ 20m) not only experience longitudinal expansion and contraction under stress, but also complex deformations such as lateral displacement and angular displacement, which traditional expansion devices are difficult to adapt to. The MS series comb plate expansion device is designed with modularity and can be assembled and installed according to bridge curves and oblique angles. The comb plate is matched with sliding supports, allowing the beam to flexibly move in multiple directions. At the same time, the sealing strip and comb plate form a double seal to prevent rainwater leakage;
Typical value: Such as urban circular overpasses, mountainous highway overpasses, and wide sections of sea crossing bridge approach spans, this device can adapt to the complex deformation requirements of bridges, ensure synchronous deformation of expansion devices and beams, avoid gaps, leaks, or structural cracks, while maintaining the flatness of the bridge deck and meeting the smoothness of vehicle curve driving.
4. High grade highway bridge (expressway, first-class highway)
Application logic: High grade highways have a large traffic flow (daily traffic volume ≥ 10000 vehicles) and fast vehicle speeds (design speed of 80-120km/h), requiring high requirements for the smoothness, durability, and safety of telescopic devices. The MS series comb plate adopts a structure of "high-strength comb teeth+wear-resistant slider+elastic seal", and the comb teeth surface is quenched (hardness ≥ HRC50), with excellent wear resistance; The slider is made of polytetrafluoroethylene (PTFE) or modified nylon material, with a low friction coefficient (≤ 0.15), reducing the resistance during beam expansion and contraction; The sealing strip is made of EPDM material, which is resistant to aging and has strong waterproof properties;
Typical value: such as national highway trunk bridges and urban agglomeration expressway bridges, this device can ensure that vehicles travel at high speeds without jumping or noise, while resisting erosion from rain, ice, snow, and salt (coastal or winter de icing areas). Its service life can reach 10-15 years (traditional expansion devices usually have a service life of 5-8 years), reducing maintenance costs in the later stage.
5. Special environmental bridges (coastal, high-altitude, heavy-duty highway bridges)
Application logic:
Coastal bridges: Faced with high humidity and high salt spray environments, corrosion is prone to occur. The MS series comb plate adopts stainless steel comb teeth or carbon steel surface hot-dip galvanizing/spraying treatment, and the sealing strip has salt spray corrosion resistance to avoid corrosion and failure of the expansion device;
High cold bridges: In winter, the temperature is low (≤ -30 ℃), and the sealing rubber strip of traditional expansion devices is prone to hardening and cracking. This device uses cold resistant EPDM rubber strip, which maintains elasticity at low temperatures. At the same time, the comb tooth gap design can avoid expansion obstruction caused by ice and snow accumulation;
Heavy load bridges: such as mining area and port dedicated highway bridges, with large vehicle axle loads (≥ 150kN) and frequent traffic. The high-strength comb plate and thickened base design of this device can withstand heavy load impacts, avoid comb bending and fracture, and ensure structural safety;
Typical value: Such as cross sea bridges on coastal highways, highway bridges in high-altitude northern regions, and heavy-duty highway bridges in mining areas, this device can adapt to harsh environments and heavy load requirements, reduce expansion device failures caused by environmental corrosion or load impact, and ensure long-term stable operation of bridges.
2、 Core application function: solving key pain points of bridges
1. Absorb multi-directional deformation and protect bridge structures
Core function: Through the cross meshing design of comb plates, it absorbs multi-directional deformations such as longitudinal expansion, lateral displacement, and vertical rotation of bridges, avoiding mutual compression and pulling between beams and abutments, and between beams due to deformation, which may cause concrete cracking and steel corrosion;
Application manifestation: For example, the expansion and contraction of the beam ends of continuous beam bridges and the deformation of the tower beam connection of cable-stayed bridges, this device can flexibly adapt to different directions of displacement, ensuring that the bridge structure is not damaged by deformation stress.
2. Ensure smooth driving and reduce traffic noise
Core function: The comb plate has a smooth surface and small gaps, ensuring smooth contact between the tire and comb plate during vehicle operation without any noticeable jumping sensation; At the same time, the low friction fit between the comb plate and the slider reduces mechanical noise during beam expansion and contraction;
Application manifestation: such as urban elevated bridges and highway bridges near residential areas, this device can reduce vehicle traffic noise (10-15 dB lower than traditional telescopic devices), improve driving comfort and surrounding environmental quality.
3. Sealed and waterproof to prevent structural erosion
Core function: Install EPDM sealing strips under the comb plate to form a closed waterproof barrier, preventing rainwater, ice and snow melting water, and debris (mud, stones) from entering the interior of the expansion device and the gaps at the ends of the bridge beam;
Application manifestation: To prevent rainwater infiltration from causing carbonation of concrete and corrosion of steel bars at the end of the beam, extend the service life of the main structure of the bridge, especially suitable for bridges in rainy and coastal areas, and reduce bridge diseases caused by water damage.
4. Simplify installation and maintenance to improve construction efficiency
Core function: The MS series adopts modular design, and components such as comb plates, bases, sliders, and sealing strips can be prefabricated for production. During on-site installation, only slots need to be reserved, the base needs to be fixed, and the comb plates need to be spliced without complex processes; During later maintenance, damaged comb plates or sealing strips can be replaced separately without the need for overall removal;
Application manifestation: For example, in bridge renovation and expansion projects, as well as old bridge expansion and contraction device renovation projects, this device can be quickly installed and replaced, shorten the construction period (usually 1-2 days for single span installation), and reduce the impact on traffic flow.