The hottest new development trend of vibratory rol

Abstract: This paper mainly introduces the development trend of foreign vibratory rollers in vibration technology, automation, intelligence, humanization, green environmental protection, and provides a reference for the development of domestic vibratory rollers

key words: development trend of vibratory roller

compared with static roller, vibratory roller has the advantages of good compaction effect and high production efficiency. Today, with increasingly strict requirements for project quality and progress, it is unanimously favored by the majority of construction units. With the continuous improvement of vibratory compaction technology and control technology, especially the rapid development of microelectronics technology, automatic control technology and networking technology, the development prospect of vibratory roller is even brighter. Here, some development trends of foreign vibratory rollers are introduced, hoping to enlighten the development of domestic rollers

1 development of vibration compaction technology for super high-grade pavement

in order to control the compaction of super high-grade pavement materials with appropriate temperature, it is necessary to increase the rolling speed and vibration frequency to maintain the time interval of vibration compaction of mixed materials, so as to ensure the compactness. At present, the major roller manufacturers in the world have carried out research and development in this area. Caterpillar company, dynapark company, Sakai company, haiparker company and others have improved the vibration frequency and exciting force of the two wheel vibratory roller. The operator can comfortably and automatically control the vibration frequency and amplitude of the vibrating wheel to achieve high-speed compaction while ensuring quality. Due to the multi-level frequency and amplitude set from high to low, these products can compact more structural types of soil at high speed, so as to improve the construction scope and construction efficiency

2 continuous innovation of vibration technology

in order to meet the use requirements of high compactness accuracy, BMW has developed a double steel wheel automatic control compaction system "variomatic", referred to as BVM. The characteristic of this system is that it can automatically distinguish and control the required compaction strength, which can also be called automatic amplitude modulation compaction system. Its main working device is composed of two reverse rotating shafts. The centrifugal force generated by rotation during operation is geometrically superimposed to form directional vibration. The directional vibration system is the foundation of BVM. The unique feature of BVM system is that the vibration direction can be changed. It can automatically adjust the vibration direction of directional vibration. During the compaction process, the vibration direction can be adjusted according to the change of the stiffness of the compaction surface or the change of the driving direction of the roller, so as to achieve the purpose of adjusting the amplitude

others, such as dd-130 double drum Tandem Vibratory Roller of Ingersoll Rand Company in the United States. It has an automatic reverse eccentric device in each vibrating wheel, which can realize the output of 8 different exciting forces from 0.7 to 1.6T, and can basically meet the rolling needs of all soil types of pavement

in addition, there is horizontal vibration compaction technology. It uses the principle of alternating shear strain in soil mechanics to rearrange the particles of soil and other materials for compaction. Hamm company of Germany first developed an oscillating roller based on this principle. It uses two eccentric shafts to rotate synchronously to produce parallel eccentric forces and form alternating torque, which makes the vibrating wheel produce oscillation and form compaction on the ground

in order to enhance the compaction effect and improve the compaction efficiency, some foreign products also generally adopt ultra-high frequency vibration technology, with a vibration frequency of more than 66.7hz, so that the roller can quickly reach the high output force required by the electrical parts, including the load measurement system and the deformation measurement system, which can effectively improve the compaction speed

3 development and application of timely monitoring, automation, intellectualization and networking technology

with the rise of modern new technological revolution, especially the rapid development of microelectronics technology, automatic control technology and computer technology, compaction machinery is developing towards automation, intellectualization and roboticization

in terms of compaction process monitoring technology, BTM compactor in Germany uses the dynamic characteristics of the interaction between vibrating parts and foundation to judge the compaction process. The principle of this method is based on the fact that when the ground is gradually compacted under the action of vibrating parts, the dynamic characteristics of the ground and the machine system are also changing. This change will indicate the relative value of the change in the bearing capacity of the ground, thus reflecting the degree of compaction of the ground. Its btm05 computer compaction control measurement system can continuously and real-time measure and process the change of compaction degree in the compaction process, and can display or print the compaction quality of each point of the compaction layer profile. On this basis, the company also developed an off-line processing system bcm03 that can be connected with a microcomputer. After data processing, the compaction quality map of the whole compaction area can be drawn. At the same time, microcomputer technology has been widely used in various working systems, such as the monitoring of the working system, the anti slip device of the driving system, the automatic fault detection system of the whole machine, etc. in the road roller products of German BOMAG, Sweden Dynapac and other companies. Their basic principle is to compile the relevant working condition information of each working system of the whole machine into software in advance. During the working process of the whole machine, the sensors installed on each working device continuously send relevant signals or data during the operation of the equipment to the microprocessor, and the corresponding text, image or acousto-optic information (alarm) will be displayed on the LCD screen after being processed by the computer. In case of non alarm, the operator can also query the concerned working information of the whole machine through the system at any time, such as temperature, speed, oil volume, etc

in the application of intelligence and networking, German BOMAG company has applied network transmission and satellite positioning system (GPS) to corresponding products. Through this system, the position of the roller can be recorded very accurately, and the compaction position can be determined and the compaction quality can be guaranteed. Through the GPS pulse device installed on the roller, it transmits the working conditions of the whole machine, such as the working area, working track, rolling compaction and other GPS signals, to the space satellite; The space satellite will form an image or data information from the collected information and re send it to the GPS receiving device installed on the roller and display it on the PC; At the same time, it can send instructions to the roller through the GPS signal device on the ground, start the automatic amplitude modulation mechanism, and adjust the magnitude of the working excitation force at any time, so as to meet the specified compactness requirements of the pavement. Some road rollers are also equipped with direction sensors and ultrasonic transmitting and receiving devices around the body. If the roller encounters obstacles while driving, the receiving device will receive the reflected waves reflected by the obstacles and trigger the alarm to remind the driver to pay attention; If it is connected with the operator's hand-held sensor remote control, the long-distance free transmission of information can be realized, and the momentum is extremely rapid to realize the unmanned driving of the whole machine

4 pay attention to the concept of humanized design and improve the comfort and safety of products

foreign construction machinery products have done a lot of meticulous and effective work in humanized design, trying to meet the aesthetic, practical, comfortable and other needs that operators hope to achieve. In addition to the previously mentioned rise and fall of seat height, front and rear left and right sliding and rotation, front and rear and angle adjustment of backrest, consideration is also given to such things as the up and down floating of armrest, the follow-up of steering wheel angle, the coordination of pedal and handrail, the setting of document bag, the allocation of first-aid kit, the layout of console, the installation and layout of instrument lighting, and the complexity and simplicity of operation. These designs fully consider people's physiological characteristics and behavior habits, Try to reduce the labor intensity of the driver, so as to reduce operational errors and meet the user's willingness to use to the greatest extent

the comfort of construction machinery covers a wide range, such as the driver's driving environment, operation process, maintenance and maintainability, among which the driving environment is the most important. At present, the driver's cab of foreign vibratory rollers is gradually approaching the standard of automobile driver's cab, which is manifested in the fact that a large number of modular shaped parts are used in the internal structure, with exquisite appearance and comfortable and reasonable overall layout. According to the characteristics that the roller often needs to drive forward and backward, special attention is paid to the pursuit of wide field of vision and equal sight distance effect, and is equipped with ventilation, air conditioning, heating, television monitoring and other facilities. In terms of operation and control, electric control or electro-hydraulic joint control are widely used, making the operation portable and flexible. In terms of the overall structure of the cab, the application of ergonomic plastic art is increased. There are super large tempered glass doors and windows around the cab, the luxury driver seat can slide and move forward and backward, left and right, up and down, the backrest angle can be adjusted arbitrarily, and the cab can be turned over or slid as a whole, which improves the convenience of internal maintenance of the equipment. A multi-layer electronic rubber damping element is set between the cab and the fuselage, and the vibrating wheel is flexibly connected with the fuselage, so that the driving part and the vibrating part of the roller are on two units, and the power is transmitted by the hydraulic system, but the vibration of the vibrating wheel can rarely be transmitted; In addition, the cab adopts high-quality rubber components, and an elastic shock absorber is installed between the vibrating wheel and the frame, which greatly reduces the amplitude of the seat, properly solves the contradiction between improving the vibration effect and preventing harmful vibration, greatly improves the comfort of operation and the convenience of maintenance, and embodies a high man-machine modeling art

in terms of safety, the cab with anti overturn and falling object protection or independent anti overturn and falling object protection devices are widely used, and heavy engineering seats and safety belts are equipped. In the braking system, the caliper disc pneumatic hydraulic unpowered braking system is widely used, which can realize the effective braking of the whole machine in the emergency of losing power. In the drive system, the anti slip technology is adopted, which greatly improves the driving performance of the whole machine and makes the gradeability of the whole machine reach more than 50%. For example, the sp2012 d-hc vibratory roller developed by Benford company in the UK using this technology can compact the material containing 8% bentonite concentrated sand on a 1:2 slope, and the specified compactness can be achieved by several times of vibratory compaction

5 pay attention to green environmental protection design

in order to meet the increasingly stringent environmental protection requirements, foreign vibratory roller manufacturers have introduced the concept of green environmental protection design. At present, it is mainly to reduce engine exhaust emissions, vibration and noise. At the beginning of the design and trial production process, some foreign vibratory rollers pay attention to the causes and parts of reducing noise, vibration and waste gas, and actively explore and take measures to eliminate them. For example, in terms of exhaust gas purification, some products produced by caterpillar can meet EPA Tier II and EU stage II emission standards through the application of new technologies such as electronic fuel injection, exhaust gas recirculation and catalytic purifier; Due to the new ADEM micro processing diesel injection electronic control module, the injection pressure of some diesel engines is increased by 22%, which improves the degree of fuel atomization, and the combustion is full and efficient. It not only reduces the content of harmful substances in exhaust gas, but also increases the output torque by 35%. In terms of noise reduction, mechanical, hydraulic and tire noise can be reduced by using a large number of elastic supports and elastic damping elements, improving the manufacturing and assembly accuracy of moving bodies and actuators in various mechanisms, improving the tightness of the cab, and selecting appropriate tires; Photoelectric induction is one of the more advanced technologies. Some manufacturers' products use covers with sound-absorbing materials on the surface, which plays a good sound insulation role and makes the external noise