The advantages of physical arch bridges high school physics is very simple, come and try it .

The advantage of an arch bridge is that the pressure of a moving object on the bridge body will be less than the gravitational force of the object.

Take the top of the bridge for analysis.

If the object is moving with velocity v then the centripetal force mv 2 r=mg-n n is required as the supporting force of the bridge.

It can be seen from this that n=mg-mv 2 r, the faster the object moves, the less pressure it has on the bridge.

The advantage of the arch is not in the span, far less than the cable-stayed and suspension, its advantage is that the structural part of the work is not subjected to tension, but pressure, and the performance of pressure-resistant materials is exerted, which is why some ancient stone arch bridges can be preserved to this day.

The force here is also that the axial force is only pressure, and if it is eccentric (that is, not through the tangential direction), there will be a force moment on the application point, and bending deformation will occur, which is unfavorable. The ideal curve can make the entire arch is subject to radial pressure, this curve is called (there is a name, let me think about it), yes, called the reasonable arch axis.

The arch bridge changes the downward pressure of the car on the bridge vertically to the downward pressure obliquely, which is gradually transmitted and finally transmitted to the bridge pier! The way the force is transmitted is similar to stacking several objects on a flat surface, with the top object transferring the gravitational force through the pressure to the pressure of the bottom object on the ground!

The pressure of a moving object on the bridge will be less than the gravitational force of the object.

Take the top of the bridge for analysis.

If the object is moving with velocity v then the centripetal force mv 2 r=mg-n n is required as the supporting force of the bridge.

It can be seen from this that n=mg-mv 2 r, the faster the object moves, the less pressure it has on the bridge.

The reason the bridge is designed upwards is that there is less pressure on the bridge as cars pass through the middle of the bridge; In contrast, concave bridges are subjected to more pressure.

Since the car needs to have a centripetal force f when passing through an arc, it is synthesized by the gravitational force mg and the supporting force n.

On the arch bridge: f=mg-n n=mg-f

In concave bridges: f=n-mg n=f-mg

From the above two equations, it can be seen that the n of the arch bridge is smaller, and n is the supporting force of the bridge to the car, and its magnitude is equal to the pressure of the car on the bridge. Therefore, the arch bridge is beneficial to the design of the structural strength of the bridge.

1. The bridge should not be designed to be arched upward, but should be designed to be concave. Because the car has a certain potential energy before going down, this potential energy can help it reach the end of the bridge smoothly. However, the bridge with an upward arch does not have this advantage.

2. The bridge is designed as an upward grinding hole, because when the car passes through the middle of the bridge, the pressure on the bridge is small; In contrast, concave bridges are subjected to more pressure.

1. The bridge is made into an arch, and the force of the bridge is concentrated at both ends of the bridge (pier), so that when the force is applied on the bridge, the force can be transmitted to both ends (pier).

2. The arc bridge conforms to the principle of mechanics, the arch bridge will decompose a part of the gravity into horizontal force, so that the bearing capacity of the bridge is greatly improved, under the action of vertical load, the two ends of the arch not only have vertical reaction force, but also have horizontal reaction force; Due to the action of the horizontal reaction force, the bending distance of the arch is greatly reduced. The well-designed arch shaft mainly bears pressure, and the bending distance and shear force are small, so the spanning capacity of the arch is much larger than that of the beam.

3. It also has the advantages of material saving, convenient construction and durability. Therefore, it is now widely used in the construction of various large and small bridges.

The characteristics of the arch bridge are as follows:

Advantages: 1. Large spanning ability.

2. Be able to fully use local materials.

3. Good durability and low maintenance and maintenance costs.

4. Beautiful appearance; It is simple in structure and easy to master.

5. The dead weight is large, and the corresponding horizontal thrust is large.

Cons: Envy.

There are many support constructions, many construction processes, inconvenient mechanized construction, and long construction periods; Porous arch bridges need to be provided with one-way thrust piers; The building height of the upward-bearing arch bridge is high.

An arch bridge refers to a bridge in which the arch is used as the main load-bearing component of the structure in the vertical plane. The vertical load is transmitted to the arch through the curved arch, which was not originally used for landscaping, but in the project to meet the purpose of flood discharge and navigation under the bridge. In the process of formation and development, the bridge body is curved, so it is often called a curved bridge in ancient times.

Origin of arch bridges: China's arch bridges were built in the middle and late Eastern Han Dynasty and have a history of more than 1,800 years. It is gradually developed by outrigger wood and stone girder bridges, bracing bridges, etc.

In the process of formation and development, the shape is curved, so it is often called a curved bridge in ancient times. In ancient documents, the words "囷", "窌", "dou", "urn" and other words are also used to represent the arch.

Arch bridge. The shape is beautiful, the curves are rounded, and the sense of dynamism is rich. Single-arch such as Beijing Summer Palace jade belt bridge, the arch coupon is parabolic, the bridge body is made of white marble, the bridge shape is like a weeping rainbow lying wave.

Perforated arch bridges are suitable for wide water surfaces with large spans, and most of them are common.

The third, fifth and seventh holes, the famous seventeen-hole bridge of the Summer Palace, about 150 meters long and about one meter wide, connect Nanhu Island, enrich the level of Kunming Lake, and become the opposite scene of Wanshou Mountain. The "open-shoulder arch" of Zhaozhou Bridge in Hebei Province is the first of its kind in China, and there are many imitations of this form in gardens, such as one in the East Garden of Suzhou.