Directional blasting has made an important contribution.
Blasting technology plays a key role in large-scale projects such as railways, mines and reservoirs.
Blasting technology will be used to dig tunnels for mining roads and demolish old buildings in cities.
With the development of economy and the increase of engineering construction, blasting has been paid more and more attention.
As a science and technology, blasting is widely used, but it is undoubtedly the most important and common application in engineering. Drilling and blasting are used in mining to dig tunnels, repair railways and highways, and some are also used in water conservancy projects, and now they are also used to demolish buildings in cities.
It is irreplaceable to use the huge energy generated to destroy the original structure of an object.
The blasting of cold water tower is not an independent project, but it is an important process, especially in projects without this process such as stone excavation and mining.
At present, China has a well-developed railway and highway transportation network. It is conceivable that building these roads will encounter many high mountains. A mountain lies between these two places. If you want to build roads, you must make the mountains disappear. At this time, blasting will play a decisive role.
The railway construction that started in 1950s laid the foundation of modern railways in China.
Our country has a vast territory and complex terrain, so it is common to cut mountains and dig pits when laying railways. The amount of earthwork is very large, ranging from tens of thousands to hundreds of thousands of cubic meters. It is inconceivable that such a big project should be completed entirely by manpower. Later, the Soviet Union's large-scale blasting technology was introduced, with tens, hundreds or even thousands of tons at a time, which could blast hundreds of thousands to tens of millions of cubic meters, greatly saving manpower and accelerating the construction period.
The fifties and sixties were also the era of great development of railway blasting technology. Due to the extensive use of blasting construction method, some new railways were laid and opened to traffic ahead of schedule.
Taking baoji-chengdu railway as an example, 148 chamber blasting was carried out in the whole line, and 2.49 million cubic meters of earth and stone were completed, accounting for 3.8% of the total earth and stone. 1 16 blasting was carried out on the yingtan-Xiamen railway, and 2.39 million cubic meters of earth and stone were completed, accounting for 7. 1% of the whole line.
Many railways like 10 were opened by blasting, so blasting played a great role in the history of railway construction in China.
Introduced technology Blasting technology was introduced from the Soviet Union. Before the founding of the People's Republic of China, cutting mountains was simply called drilling and blasting. It is entirely based on experience. No one regards it as science and technology, and its efficiency is very low.
After the founding of New China, engineering blasting technology was introduced from the Soviet Union, which improved the efficiency of railway construction by more than 20 times, and the effect was obvious. Soon, this technology was also concerned by other parties.
For example, building a dam requires a lot of stones, so we studied how to blow up the hills suitable for building reservoirs in mountainous areas.
Engineering blasting was used to form the foundation earthwork of the dam, which was then called directional blasting dam construction method.
This method has been used in many dam constructions, such as 1959, the Three Gorges Dam Project, which was blasted in Yuan Xian County, Shaoguan, Guangdong Province at that time. 1300 tons of blasting rock,1000000 cubic meters, piled up into a rockfill dam with a height of more than 60 meters. This is unthinkable if it is manual.
Nowadays, the blasting technology used by water conservancy departments is even more powerful. There are several large power stations at the foot of the mountain. The power stations are built in the mountains, that is, the mountains are hollowed out by blasting.
The high degree of mechanized construction of stone engineering puts forward new requirements for blasting, because to solve the problems of digging, loading, transporting and unloading in mechanized construction of stone engineering depends first on whether there is a rock crushing technology that meets the requirements of mechanized construction.
Large blasting has its advantages, but the crushing is uneven, and the secondary crushing will inevitably affect the improvement of mechanical efficiency. However, the general hand drill drilling and blasting method is extremely low in labor productivity, which is far from meeting the operation and production needs of digging and loading machinery.
Therefore, deep-hole blasting technology must be applied and developed, that is, according to the bucket capacity of digging and loading machinery, the size of rock fragmentation, the shape of blasting pile and the volume of blasting drop should be reasonably controlled to give full play to the use efficiency of machinery.
The engineering blasting technology in China has reached a high level in terms of blasting scale and blasting accuracy.
So far, China has loaded more than 30,000 tons at a time.
The first time was in Gansu Baiyin Mine 1956. At that time, it was loaded with 15000 tons, but it was bombed twice, with the help of the Soviet Union.
The second time was at 197 1. At that time, Panzhihua, Sichuan was building a steel plant. There is a lion mountain in the steel factory. There are more than11100,000 square meters of stones on the top of the mountain. Iron ore is below 60 meters, and all of them are rocks. If drilling is difficult and dangerous, organize blasting and install 65438+.
The third time was 1992. There is a hill at Zhuhai airport. This mountain has120,000 square meters and is 10 meters high. This is a threat to the take-off of the plane, so it is necessary to blow it up. It was loaded with 12000 tons, and it was blown up to the mountain. Known as the world's first explosion, it has never been so big in the world.
The precision of accurate blasting engineering blasting is very critical and is the goal to be pursued.
In addition to the deep hole blasting just mentioned, there are more advanced and accurate smooth blasting technology and fine blasting technology.
When the Three Gorges Dam is built on the Yangtze River, a navigable waterway is excavated from a mountain, which is called a ship lock.
This mountain is about 4 kilometers long, and the lock built is 2 kilometers long. The excavation volume of this ship lock is about 40 million cubic meters, and the engineering quantity is huge.
In engineering blasting, a pier 60 meters wide and 50 meters deep should be opened in the middle of the ship lock. If it cannot be completed by ordinary blasting methods, deep hole, presplitting and smooth blasting techniques must be adopted.
What is presplitting blasting? That is, before blasting in the main blasting area, a through crack with a certain width is broken along the design contour line. Blasting vibration wave can't propagate after buffering and presplitting, and it won't do harm to the slope surface, and it can also protect the slope safety there.
Smooth technology is to reserve a protective layer (also called smooth surface) after blasting, punch a row of holes and blow it up.
In China, this technology has developed to a very high level and played a great role in many aspects.
Without smooth presplitting, it is difficult to complete the Three Gorges Shiplock.
Now there is fine blasting, and the actual effect is consistent with the target set by blasting, which is very accurate.
In 1970s, presplitting blasting and smooth blasting were successfully applied in the soft and hard rocks of Gezhouba Hydro-junction and Dongjiang Hydropower Station in China, and then they were rapidly popularized.
"The World's No.1 Blasting" was completed in China, with the rapid development of presplitting blasting and smooth blasting, and the rapid development of blasting technology. Then, compared with other advanced countries in the world, has the current blasting technology in China reached a very high level?
Large-scale blasting technology was introduced from the Soviet Union, but the blasting engineering technology developed with the social production practice.
During the decades of economic construction in China, there are many blasting projects, such as the construction of railway tunnels with a total length of more than 3,000 kilometers.
In this way, through large-scale application, continuous summary and research, and in-depth study of related basic disciplines, our blasting technology has made great progress.
For example, due to the progress of drilling machinery, the efficiency of drilling holes is much higher than that of manual drilling. Therefore, borehole blasting, especially deep-hole blasting technology, has been widely popularized in China, replacing chamber blasting with high labor intensity and poor safety.
At present, the main slope of hydropower station in China must be pre-split or smooth blasting, which is in a leading position in the same industry in China and reaches the advanced level in the world because of its large scale and excellent excavation quality.
Compared with foreign countries, the whole blasting technology is not worse than them, and it has advantages in the selection of blasting parameters, the principle of charge arrangement and the combination of engineering geological conditions.
In the demolition of large buildings in cities, directional blasting shows its power.
Blasting is the energy of blasting engineering.
Engineering blasting is called industry, which is different from ordinary initiation or violence. It is characterized by mass production, low price, simple and convenient use and relative safety, but there are not many varieties.
It was widely used in the 1950s. At that time, many varieties were used, so it was dangerous and prone to accidents.
With the increase and continuous improvement of blasting practice, the safety in use at present is very high and the variety is relatively fixed.
Usually ammonium, that is, fertilizer powder, and.
At present, the most striking thing in engineering blasting is the demolition of old buildings and chimneys in the city. It is often seen that a high-rise building is demolished instantly, which is very practical and spectacular.
Engineering Blasting At present, many old buildings and equipment are no longer suitable for use and need to be demolished, but for example, a large chimney, one or two hundred meters high, is very dangerous if it is demolished manually, and very safe if it is blasted.
Demolition of houses is the same, many of them are steel structures and concrete structures, which are difficult to do without blasting.
Demolition of a building by blasting technology is not to blow up and smash the building, but to use the generated energy to destroy the strength of the main stress components of the building, so that its structure loses its bearing capacity and becomes unstable under its own gravity, which makes the gravity of the building and the ground support force form a rotating couple and produce oblique displacement, thus causing its deformation and failure, leading to collapse, impact on the ground and disintegration.
Due to the huge demand of mine blasting in China and the accumulated experience for decades, the blasting technology of urban buildings has developed rapidly.
Hundreds of blasting demolition of various buildings have been successfully carried out in large and medium-sized cities, which shows that China demolition blasting technology has the ability to successfully demolish large-area, towering and special structures in complex environments, and has the characteristics of high efficiency, rapidity, low cost, safety and reliability. Especially in dense and complex residential areas, demolition blasting is not uncommon, which shows that the engineering blasting technology has developed to a high level.
Directional blasting is to dig holes in the appropriate parts of the building foundation and fill them.
At the moment of detonation, a gap will be formed at the bottom of the building, which will make the building unstable and collapse.
The implementation of directional blasting must be carefully designed: firstly, the blasting area should be roughly determined according to the engineering needs and site topography and geology, and then the blasting design should be carried out.
When designing, we should make full use of the terrain, distribute the medicine reasonably and determine the dosage accurately; It must also include cavern construction, charge blasting, initiation network and other related projects; Check the impact of blasting on the surrounding environment, including the damage range of bedrock, the vibration value of nearby ground and underground buildings, the distance between flying rocks and air shock waves, etc.
When demolishing old buildings by directional blasting, it can effectively control the scope and direction of blasting and avoid damage to surrounding buildings, which is its most obvious feature.
In fact, China has been studying directional blasting technology since 1958, and the technology is becoming more and more advanced.
At present, the directional blasting technology in China can blast one million cubic meters of earth and stone at a time, and the consumption reaches thousands of tons.
As long as the safety regulations are strictly observed and the protection work is done well, any scale and type of blasting can ensure safety.
Safe Blasting With the development of China's modernization, the blasting environment is becoming more and more complicated, and the requirements for blasting safety may be higher and higher.
Although the current engineering blasting technology in China has reached a high level, blasting operation is a dangerous job. As we all know, a blasting accident may cause casualties.
Engineering blasting and property losses may also lead to environmental damage.
For the sake of safety, in engineering practice, there are often many requirements and standards that need our efforts to solve, such as strictly controlling vibration effect, blasting shock wave, noise and dust, preventing the threat of electrical interference to blasting operation, paying attention to soil and water conservation and environmental protection.
The safety of blasting operation has always been a problem that all parties attach importance to, and professional norms, systems and technologies have been formed at present.
For example, since 1992 promulgated the Safety Regulations for Demolition Blasting in China, the safety management of blasting engineering has been effectively promoted and remarkable results have been achieved through the demolition of blasting classification management, qualification examination of undertaking units and personnel, training and examination of blasting technicians, review of blasting design and safety evaluation.
The research on safety technology of blasting operation is considered from two aspects. On the one hand, it is the safety technology of mixed materials and the damage it causes, which is active.
On the other hand, it is a passive aspect to take protective measures against the hazards caused by blasting.
Both of them are equally important to prevent the damage caused by blasting, but there are often uncertain phenomena and consequences in specific blasting projects. Therefore, it is necessary to make a detailed analysis and study on the specific situation of each project, so as to take corresponding countermeasures.
At the same time, despite the continuous progress of technology, we must pay attention to each working procedure and work carefully in accordance with safety regulations.
As long as the safety regulations are strictly observed and the safety technical measures and protective measures are taken correctly, any scale and any kind of blasting can ensure safety.
Some provisions of safety regulations are based on experience and theory, and some even sum up the lessons of blood. Therefore, we must overcome the paralyzed thinking, strictly implement the safety regulations, and never rashly "break through" the prescribed "framework" just because there is nothing wrong.
There are some examples of unsuccessful blasting, such as the failure of blasting, the failure of the direction of blasting scheme after directional blasting, and so on.
These examples warn that mistakes in any link, from blasting design, quality, blasting construction to initiation network connection, will affect the effect of blasting engineering and even cause serious consequences.
Blasting operation is very complicated for both the old building itself and the surrounding environment. It requires not only a detailed investigation of the structure of the blasting body (including construction defects) and an analysis of the stress situation, but also an analysis of the reliability and safety of technical measures (such as pretreatment, repair, support, etc.). For possible accidents, emergency plans should be made in advance to avoid safety accidents and unnecessary losses.
People pay more and more attention to the environmental protection of the project, and exploring the demolition blasting technology without pollution has always been the goal pursued by blasting workers.
The easiest way to build a bunker to protect objects is to cover the objects that need protection with materials such as straw bags and bamboo basketry. For houses and mechanical equipment, it is often necessary to erect bent frames at the head and top, and cover barbed wire with wooden boards or Beijing buses to resist the impact of more flying stones and strong air shock waves; Some important engineering buildings are drilled with earthquake-proof holes or presplitting blasting is used to separate the blasting area from the protected buildings or engineering facilities.
Water can be used to reduce dust in the blasting construction of water tower in Angang 1780 continuous casting and rolling project.
For example, in the demolition blasting project of an old gymnasium in a city, the dust was well suppressed by measures such as pre-demolition, masonry, plastering, pre-soaking the blasting wall, covering 3000 water bags on the roof, laying a pool on the ground, setting a water curtain around the high-pressure pipe network, putting fire water bombs by helicopters during blasting, and spraying water mist by fire engines after blasting. After blasting, the dust concentration on the windward side of the roof of the adjacent hotel is 0.94 mg/m3, which is less than the urban dust environmental protection standard 1.
In terms of noise control, the key is to put an end to urban use, do a good job of covering and protecting the blasting site, and do a good job of sound barrier in the blasting area, which will play a certain role in reducing blasting noise.
From the technology itself, innovation is the source and motive force of the development of blasting technology.
Blasting involves advanced mathematics, structural mechanics, blasting mechanics, material mechanics, architecture, engineering geology and other disciplines and fields, and we should constantly absorb and integrate the latest achievements in these fields.
In, drilling technology, surveying technology, safety technology and other aspects have developed rapidly. Some high-precision non-electric, electric and on-site mixed trucks have been tried in water conservancy blasting engineering, and some need to be further popularized.
Blasting technology has reached the stage of precise blasting, which requires more in-depth blasting theory, improving energy utilization, computer blasting simulation technology and safety research, which is of great significance for optimizing design and improving blasting effect.
Related technology scientific control of blasting engineering construction control blasting control blasting technology is a new blasting technology based on modern comprehensive disciplines and serving engineering construction. It has developed rapidly at home and abroad since 1950s and 1960s.
Especially with the emergence of new varieties and millisecond blasting technology suitable for controlled blasting, controlled blasting technology at home and abroad has been applied to the demolition of urban buildings, piers and foundations, tunnel excavation, highway reconstruction and other projects.
In recent years, combined with the rapid development of capital construction, controlled blasting can greatly reduce the labor intensity, significantly shorten the construction period and ensure safety, thus creating obvious economic and social benefits, and its application scope is also expanding day by day. It has been applied to the demolition of super-high-rise buildings and structures with complex structures, the excavation of submarine tunnels, the removal of offshore reefs and the rescue of injured people after earthquakes, and has achieved remarkable results with good quality, high speed and low cost.
The so-called controlled blasting refers to strictly controlling the process of time and energy release and the process of medium crushing according to the requirements of the demolition project, the surrounding environment and the specific situation of the demolition object, so as to achieve the expected blasting effect and strictly control the damage range within the safe allowable range.
The key is to control the blasting range, blasting hazard and blasting effect.
Specifically, according to the shape, structural size, structural characteristics, structural strength (reinforcement arrangement), environmental safety and specific requirements of blasting, reasonable blasting control technical measures such as hole arrangement, drilling, charging, connection, protective covering, vigilance and initiation are carried out, and reasonable millisecond millisecond millisecond subsection initiation technology is adopted according to the situation, and the single initiation quantity and initiation sequence are strictly controlled. In order to achieve the purpose of not only controlling the possible explosion.
The new technology of controlled blasting is very skillful, flexible and practical.
According to different engineering objects, through scientific analysis and calculation, completely different technical parameters of explosion control are adopted.
Engineering Blasting, sponsored by China Engineering Blasting Association, is a national sci-tech periodical (quarterly) approved by the Press and Publication Administration and the Ministry of Science and Technology (formerly the State Science and Technology Commission) 1995, with the international standard number ISSN1006-7051; Unified domestic serial number: CN 1 1-3657/TD.
Engineering Blasting mainly reports the practice and application of engineering blasting, and reports the new achievements and new trends in scientific research, engineering design, construction management, safety protection, product development and related theoretical research. He has made great academic achievements in AC chamber blasting, deep-hole blasting, open-pit and underground excavation blasting, demolition blasting, underwater blasting, special blasting, blasting safety, blasting test and testing, technology and equipment, and rock drilling tools.
There are also information columns such as celebrities, academic trends at home and abroad, breaking news, major activities of industry associations, and book news.