Research On Lightweight Design For The Boom System Of The Truck-mounted Concrete Pump

With the accelerated pace of the economic construct in china, and the commercial concrete industry and the construction machinery business step into a new stage, so that the concrete transportation developed rapidly, the concrete pump has become one of the indispensable equipments in construction industry, due to its maneuverability, agility and adaption in many kinds of cast condition. Now, the concrete pump is tending to be longer boom, efficient, green, and intellectual.As the fabric devices of concrete pump truck, the boom system must not onlyhave nicer rigidity and intensity, but also have nicer adaptability and dependability.The boom of concrete pump is longer mean wider range of construction and higherefficiency. But length, quality, and moment, intensity of the boom are mutual restraint.The longer the boom, the higher the intensity required to meat the conditions.Designers in order to ensure the strength of the whole structure preclude the use ofmethods to increase the structure, and the roads and transport loads and dimensions ofthe vehicle are strictly limited. Thus, only using the design methods by increasing thestructure has been difficult to meet the needs of longer arms. The method of structuraloptimization can provide a totally new and ideal design tool which can reduce theweight of a structure and improve its performance. Thus, it has been widely used inthe field of structure design.In this paper, the static and dynamic characteristics of the boom system are analyzed and the problem of the lightweight design of the boom structure is studied by finite element analysis and optimum design. The main contents of work include:（1）Static analysis of the boom system was carried out. Through a detailer finite element analysis, it obtains the strength and stiffness properties of the boom in hazardous working conditions and typical operating conditions. And obtained stress distribution and deformation conditions under different conditions. So it locates large parts of the boom in strength and stiffness margin, providing the basis for lightweight designing of the boom.（2）Simulation analysis based on flexible multi‐body dynamics. Traditional multi‐body simulation technology can traverse the various posture of the boom, and get loads and postures in the maximum force of hinge point. But it can not get the boom of the regional stress dangerous conditions. In this paper, through traversing various postures for the flexible multi‐body dynamics model of the boom to determine the risk conditions of each arms which are based on stress in different areas on each arm. So it can provide reliable boundary conditions and loads for the boom optimization.（3）The lightweight optimization of the boom was carried out. This paper discusses the optimal material distribution program of the boom in the context of dynamic and static security by topology optimization method based on shell element of the design space. And then, using size optimization, the thickness of this new structure was re‐optimized. Finally, the new optimized boom was carried out for both static and dynamic verification, to confirm the reliability of the structure.The optimization method can reduce210kg of the boom’s quality in ensuring structural dynamic and static security premise. Part of the research results of the program has been widely applied in other series truck‐mounted concrete pump. It has played a positive role in improving company’s level of design, optimizing boom structure, reducing design and manufacturing costs, and enhancing market competitiveness of products.