Steel Formwork Tunnel Lining Trolley Design

In order to ensure the stiffness and strength of the top arch formwork, the upper platform is designed as a grid-type rod structure, so that it can bear the best force and the formwork will not deform and shift during the lining process. The weakest link in the entire trolley is the lower formwork and the lower die support diagonal bar. Therefore, when designing the lower formwork, the force of the lower die should be fully calculated, and the width and thickness of the arc plate should be widened as much as possible. The support diagonal bar must pass The pressure rod is calculated stably to ensure that the inclined rod has sufficient stiffness and strength to prevent it from deforming and bending during use, resulting in mold failure. During the calculation process, the influence of factors such as the thickness of the concrete lining, slump, pouring speed, size of the aggregate, and whether it is reinforced concrete should be fully considered. The ground screw jack on the lower mold arch foot is the main force-bearing part. When the entire formwork is below the center line of the lining circle, it is completely supported by it. Therefore, its structural form and stiffness should be considered during design. During use, the jack must be firmly pressed against the ground and no looseness is allowed. If necessary, other parts can be used to reinforce it as auxiliary support to prevent the mold running and the trolley from shifting downwards. It should be noted that the rail clamps and basic screw jacks used for longitudinal positioning of the trolley must be tightened, clamped and supported on the rails, especially when lining the ramp.


This type of lining trolley is mainly used for the construction of large-span tunnels and underground caverns. If a traditional fully hydraulic lining trolley is used, the mast design cannot meet the usage requirements, causing deformation and damage of the mast. First, the mast beams are twisted and deformed, which eventually leads to mold failure. If the cross beams are heightened and the vertical beams, lower longitudinal beams, and end inclined support sections are enlarged, unnecessary waste will be caused. However, the use of grid-type lining trolleys can overcome the above difficulties. Since this type of lining trolley is used for long-span construction, its operability should be considered during design, and its working ladders and working walkways should be able to easily reach every working position.