Study On The Impression Of Improving The Vehicle Load Level On The Cost Of Prime Materials Of T-beam

With the development of road traffic, the transport vehicles are more and more complexity, and they have the developing trend of getting larger and heavier, which influence on the continuous variations of the vehicle load taking effects on the highway bridge and other main structures. If there are no restrictions to allow it to pass through, then it will naturally do a permanent damage to the highway bridge and other main structures by shortening their normal service life, and reduce the safety of using bridge significantly, and increase the maintenances and repair costs caused by leaps and bounds. But if we forbid the full cars passing through, then it will reduce the efficiency of operation and impress the development of the national economy. China has spent a large amount of manpower and material resources on hard overload control in recent years. Although the condition of overload and overrun vehicles has been improved, the phenomenons of highway bridges destroyed by overload and overrun vehicles appear frequently. Because managers are unable to change the overloading completely, together with the high cost of governing the overload and overrun vehicles, so some related departments are put forward the advice of improving the current vehicle load level. It is true for the new higher vehicle load to accommodate the new change trend to the current vehicle load well, but what impacts will been produced by improving vehicle load on the material costs of the upper structure of highway bridge, and the research on it is just the core content of this paper.This paper does research on the current standard of vehicle load firstly, combining with the standard design of the highway bridge, and obtains the prime material costs of a single piece of T-beam in the current standard of vehicle load. Secondly, based on the establishment of the structure model of the single piece of30m prefabricated prestressed concrete simply supported T-beam in the current standard of vehicle load, calculate and analyze the stress states of T-beam when we improving the vehicle load level inflicted, and adjust and modify material utilization amounts to meet with the same stress requirements of T-beam in the current standard of vehicle load by lowering or holding the stiffness, so the required structure model of T-beam is finished in different increasing extent of vehicle load level. Then, measure and calculate the increments of prime materials of T-beam respectively in the new vehicle load level, from this we can get a mathematic relation, in which the increasing extent of vehicle load level acts as independent variable and the increasing rates of three prime materials of T-beam act as dependent variables which are C50concrete, PC Strand and ordinary steel, and found out some quantitative relational expressions for the impression of improving the vehicle load level on the cost of prime materials of T-beam. At last, certain decision analyses and applications are put on these quantitative relationships to show the scientificalness, practical applicability and operability of them through the decision and application in Henan province.Currently, the management of transportation market in China has been in the bottleneck link time, once it’s come up, the proposal of improving the vehicle load level will bring about new opportunities and challenges for the situation of overload control which has fallen into a vicious circle. Whether the increased costs of prime materials of the upper structure of the highway bridge are too high by improving vehicle load level, or they will clip the building materials market, even how does the comparison of the increased costs and the costs of overload control which still need to be input to, all of these are used to make a decision that whether the proposal can be adopted. Therefore, it is very significant to study on the impression of improving the vehicle load level on the cost of prime materials of T-beam for our national transportation market management.This paper has been finished combining with the western traffic construction technology projects carried out by the Ministry of Communications, which named <<he research on design loads of bridge and their safety appraisal>>(2008318494-04).