【正文】 ze and maintain 4550% of expenses, these foreign experience of benefitting is worth we drew lessons from . Need emphasize , implement to one two road preventative maintenance can not give full play to his potential benefit and function only, put it preventative maintenance in work of highways support height of the system pay only, could fully embody its important strategic meaning and function . Choose suitable preventative maintenance machinery Carry on maintenance promptly when the road surface presents disease omen , make it not happen or continue developing, expanding , influence the stability of the basic unit, should carry on preventative maintenance. Preventative maintenance capital equipment have and irritate and sew machinery, road surface part mend homework machinery, heavy area surface punish machinery, usually. The pressure type irritates the sewing machine: Adopt artificial way to irritate and sew the homework, though can prevent the infiltration of the subsurface of rainwater , alleviate the development with further crack, but because the sealed material is not irritated deeply enough, it is very difficult to reach the lasting result. Adopt pressure type irritate person who sew can irritate deep layer to reach the crack sealed material, irritate and sew better result , can lengthen service life of road surface , raise and go the security and fortableness of the vehicle. Irritate and sew homework want and carry on clear to go on and irritate and sew after sewing first generally, greater than 3 crack of mm need and slot the homework generally. Irritate the heating that the sewing machine should be furnished with the control device of pressure, sealed material mainly or keep the device warm, for prevent spray gun hose from stop up and should take corresponding heating, keep measure warm also. The main characteristic of the pulling type is: Heat storehouse volume 470L, relatively more plete function have suitable for irritating and sewing the homework by a large scale. Pair set up yuans of hand person who push away hot to irritate heating storehouse of person who sew volume 40 L, small easy to operate using flexible, low fabrication cost pany, can look at according to work load feeling worthy of and heat cauldron again separately, suitable for hot to caulk the irritating and sewing the homework of material mainly。 s best to choose the high speed of rolling , in order to improve and press the mechanical homework efficiency of the way, reduce its quantity allocated pitch concrete glue and form analysis and research VFA (pitch consumption) of strength and pitch kind to solve pitch concrete glued and marries the strength problem. Because Marshall39。t prevent out of shape limit , pitch of mixture from almost。t ensure the pitch road surface , if insufficient debulk, optimum mixture that design will reduce serviceability , pitch of road surface, and good debulk can improve the result of a kind of nonstandard mixture effectively . So, debulk is considered to influence one of the most important factors of durable performance of road surface of pitch . Debulk course to reduce pitch course , air vent of content in the mixture, for solid particle stemming and orientating among one viscoplasticity medium course this, in the form of forming a kind of closely more knit and more effective particle to arrange. This course only takes place under the construction state in theory, but not under the traffic condition. Impact on debulk of position material on the pitch road surface collects material performance in order to reach the ideal solidity of pressing, it is very important to collect material and detailed some nature of collecting material thickly: Such as the particle form, raised angle , the absorbing water rate and surface are constructed, grade mix mixture most heavy to collect material size , thick to collect material proportion , consumption and type ,etc. , consumption of sand and powder of ore pigeonhole to pitch mixture solidity have direct influence. Under the same situation as other indexes , collect material one grade of mixture or disconnected grade mixed and mix mixture than exchanging debulk more than the single size from thick to the detailed even grade of mixture mixed , thick to collect material proportion heavy pitch mixture, must increase the strength of keeping notably , could obtain the necessary space rate . On the other hand, many sand, or detailed grade buy bituminous concrete to be very much easy to be plastic, this kind of mixture is still difficult to reach proper closely knit degree. The pitch mixture of much sand tends towards pushes and shoves and difficult with debulking under debulk function . The different kinds of packing has remarkable influence on debulk of the pitch mixture, according to survey, in a situation that other conditions are the same, ordinary silicate packing than lime stone ore powder pitch mixture and cement stone pitch mixture easy debulk bituminous concrete, pitch mixture total hole rate too very heavy difference have behind the shaping, 8% , % , 12% respectively. pitch viscidity influence pitch viscidity influence pitch mixture strength degree, and can debulk nature have something to do with mixture. At the mixture, high viscidity can pin down particle move often as debulk pitch, if pitch viscidity too low, is it collect material to be particle easy to move and push and shove in real time to press. When pitch mixture temperature is higher, pitch is it is it collect material particle rub lubricant of obstruction to overe to make, when the mixture has already been cooled, the pitch makes and bines the bination material which is collected the material particle. Generally speaking, in fixed 135 pitch being viscidity high,resistance, mixture of person who reduces space the heavier.