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Calculation and discussion have been carried about relation between compression of bored piles shaft and settlement of pile top, and valuation of ξ as composition coefficient adopted in standard method and distribution pattern of compression settlement characteristic by static load test on overlength bored piles in loess area as well as test and analysis on load-settlement characteristic of pile top together with strain test data on piles shaft.

In this paper, the relationship between the shrinkage of the thin-walled wax part in the investment casting process (ICP) and the process parameters including mold temperature, melt temperature, packing pressure and holding time are investigated through a series of experiments. The relationship is successfully described by a mathematical regression model which is based on the response surface methodology (RSM). The rationality and adequacy of the mathematical model are checked via analysis of variation (ANOVA) and a sensitivity analysis for process parameters on the dimensional shrinkage variation are conducted which shows that the contribution percentages of mold temperature, melt temperature, packing pressure and holding time are 23.77%, 43.67%, 11.85% and 16.99%, respectively. Additionally, the optimal setting of the process parameters is also obtained by calculating the desirability function. The optimal combination of the mold temperature, melt temperature, packing pressure, and holding time is 74°C, 30°C 25bar, and 5 sec, respectively.

Tower crane hoisting system is the most important structural component of tower crane components. Its structural performance directly affects the performance of the overall tower crane. Combining the characteristics of The unconventional dedicate tower crane, established the mathematical model of hoisting system, and complied the particle swarm optimization algorithm program based on improved particle swarm optimization algorithm by MATLAB language, optimized analysis of hoisting system of The unconventional dedicate tower crane, and verified the optimization results by static analysis in the end. The result shows that the optimized analysis of tower crane hoisting system is viable and efficient by the improved particle swarm optimization algorithm.

The dynamic performance of PingQiao of abnormal high tower crane is particularly important to the whole structure. Using the finite element method to set up the finite element parametric model of PingQiao of the abnormal high tower crane, and then making dynamic analysis. Taking the analysis result as the objective function of the optimization design model,and using the optimization algorithm module of ANSYS to make dynamic optimization design of PingQiao structure,the quality of PingQiao of the abnormal high tower crane is effectively reduced, the dynamic performance of the metal structure is improved,this lays the foundation for the whole optimization.

The damage mechanism of loessial soils was studied by the statistical theory.Based on the characteristics strength of loessial soils micro-unit with Weibull distribution, and parameters that described by distribution variable of Drucker-Prager creterion are used, loessial soils damage constitutive model considering damage threshold is established to reflect the full process of loessial soils failure. Conventional triaxial consolidation undrained shear test results of loessial soils are taken as example to verify the model. By comparing theoretical calculation results with test results, it is showed that the statistical damage constitutive model considering damage threshold is reasonable.

For the high hoisting height, wide using range, tower crane is widely utilized in the architecture construction, while there are some deficiencies in the high rising architecture such as chimney, so the performance can’t exerted. By virtue of computer aided technology, the finite element static analysis of metallic structure of unconventional dedicated tower crane is conducted in this paper, and the figures of stress and displacement are achieved for the two working conditions and two structures. It is proved that the results are satisfied the requirements of stiffness and strength, and also foundation is established for the further analysis.