Study On Wind Load Eoefficient Of Flat-Less Tower Crane

The tower crane the the most widely used construction hoisting machinery in construction site currently. With the continuous development of building technology, the tower crane should develop to higher height and longer arm to meet our modern construction industry. And due to the height of tower crane, we should take fully into account the influence for its construction by wind loading.Normally, the tower crane design will follow the national standard GB/T13752-1992 Tower crane design speciation. In this standard, only mention about the wind factor, wind reduction factor, wind pressure factor, windward area and Cross section ChongShiLv and for the largest structure coefficient of wind load which affect the wind loading error mostly almost cannot fulfill the development for modern tower crane construction.In this paper, choose QTP125 flat top tower crane as an example, first sum up the mainly type of carne bar by analyses its construction feature. By Computational fluid mechanics principle and ANSYS CFX software, mainly analyze the steady state response of carne bar in wind environment, steady simulation by standard Reynolds stress model, calculate the wind loading and the structure coefficient of wind load C for each construction form under operation condition.In the paper, first sorting out the crane bar for flat top tower crane, including 3 mainly type circular tube, rounded square tube and box iron, 20 kinds of different Cross section dimension. Then analyze, calculate, simulate the wind resistance and coefficient of wind load values in different draw ratio. Also simulate by two working condition, working wind speed limit and non-working wind speed limit. From the analysis result, for circular tube, the coefficient of wind load will decreases with the increase of diameter, but for rounded square tube will be the same. Also for box iron, the coefficient will be much more increase then in current specification, the main reason is that when box iron’s right side affect by wind, the right side will have lager weak wind speed area, then will have a large wind pressure. Abovementioned, those analyze result will be very importance for further analyze, also will be a supplement for current specification.Finally, by the wind load coefficient got in this paper, we process a Structure wind resistance check for QTP flat top tower crane. Compare the calculate result and original design, Rotary torque value increase 14.7%, the Wind load values of whole machine increase 64%, also we found there is obvious wind-resistant obvious defect in the original design of tower section standard knot L68B1, then have optimum structural design for that.