Analysis Of Mechanical Properties On Cargo Constraint System Of Truck Start-stop Process Based On Security Mechanism

With the rapid development of Chinese economy, transportation is improved by leaps and bounds, highway traffic soared, cargo transportation safety got more and more widely concerned. As a part of major component of cargo restraint system for road transport, cargo tie down has been received more attention. This paper's study is about mechanical properties analysis on cargo tie down of truck start-stop processes, which are manufactured by Zhejiang shuangyou Logistics Equipment Co., Ltd.Cargo restraint system composed of vehicle, cargo and tie down. In order to do comparative study, this paper choosed a heavy truck (HQG1132FD) and a light truck(BJ1039V4JD3). According to the cargo types of road transport, this paper choosed a rectangular shaped loading cargo. The tie down's limit load are 2500kg and 500kg respectively. This paper introduced different binding type, such as over top lashing, slope lashing in longitudinal and transverse direction, diagonal lashing, loop lashing, spring lashing, only the first three types are choosed as research projects.For truck's start-accelerate process, firstly analyse vehilcle's driving fore and driving resistance. Then proposed vehicle acceleration limite factors. Lastly analyse vehicle's traction characteristics, according to dynamic parameters of the two trucks, calculated and got their power characteristic curve and acceleration bottom curve, got maxmum acceleration value directly. For truck's braking process, detail four stages of braking process, including vehicle's reducing speed and brake pedal force's changes Then introduce vehicle's braking performance evaluation index, and analyse vehicle's braking efficiency(mainly refers to the brake reducing speed, braking time and braking distance). Finaly, according to China's brake test combine the actual situation of selected trucks, got the maxmum ruducing speed of braking process.Based on maxmum acceleration value of vehicle's starte-acceleration andbraking process, calculate tie down's tension force or binding force value under different binding types, which can guarantee the cargo will not slip and turn over. If the force exceed limit load, increase the number of tie downs and calculate again. By analogy, get the minimum number of tie downs. Accordind to calculation results combine the American standard, set up new formulas used for different types of lashing.