A set of serf-developed apparatus for foundation physical model were utilized to conduct model tests of the multi-element composite foundation with a steel pipe pile and several gravel piles. Some load-bearing charact...A set of serf-developed apparatus for foundation physical model were utilized to conduct model tests of the multi-element composite foundation with a steel pipe pile and several gravel piles. Some load-bearing characteristics of the multi-element Composite foundation, including the curves of foundation settlement, stresses of piles, pile-soil stress ratio, and load-sharing ratio of piles and soil, were obtained to study its working performances in silty sand soil. The experimental results revealed that the multi-element composite foundation with steel pipe pile and gravel pile contributed more than the gravel pile composite foundation in improving the bearing capacity of the silty fine sand.展开更多
A physical model facility was designed,built,and setup for conducting model tests on a composite foundation in a soil ground.The model tests were carried out on a composite foundation with different combinations of ve...A physical model facility was designed,built,and setup for conducting model tests on a composite foundation in a soil ground.The model tests were carried out on a composite foundation with different combinations of vertical reinforcement elements in the same soil ground.Via the analysis of the collected data the characteristics of the composite foundation with different reinforcing elements were obtained,including the characteristics of load-settlement curves,column stresses,stresses of the inter-column soil,pile-soil stress ratio,and load-sharing ratios of columns and soil.Results from the model tests reveal the mechanism of a composite foundation with different reinforcing elements quantitatively.It is concluded that both a composite foundation with a combination of steel pipe pile and sand column and that with a combination of concrete pile and lime column have a higher bearing capacity than the composite foundation with only sand columns with the same conditions of soil ground and loading.A composite foundation with lime column and sand column embodies no much better performance than that with sand columns only.展开更多
以热力学和动力学理论为基础,研究了 Nb 微合金钢热变形过程中铁素体相的形核及长大过程,在形核速率计算中引入变形储能、晶界凸阶及微合金元素的作用,建立了低温变形诱导铁素体相变的动力学模型,分析了热变形参数和化学成分对相变分数...以热力学和动力学理论为基础,研究了 Nb 微合金钢热变形过程中铁素体相的形核及长大过程,在形核速率计算中引入变形储能、晶界凸阶及微合金元素的作用,建立了低温变形诱导铁素体相变的动力学模型,分析了热变形参数和化学成分对相变分数和晶粒尺寸的影响.变形温度的降低和变形程度的增加,促进了α相变过程,相变体积分数增加,晶粒得到细化.C 与 Mn 含量增加的效果则相反.模型应用于热轧带钢生产过程的模拟,计算结果和实测结果吻合良好.展开更多
基金The National Natural Science Foundation of China (No.50478090)
文摘A set of serf-developed apparatus for foundation physical model were utilized to conduct model tests of the multi-element composite foundation with a steel pipe pile and several gravel piles. Some load-bearing characteristics of the multi-element Composite foundation, including the curves of foundation settlement, stresses of piles, pile-soil stress ratio, and load-sharing ratio of piles and soil, were obtained to study its working performances in silty sand soil. The experimental results revealed that the multi-element composite foundation with steel pipe pile and gravel pile contributed more than the gravel pile composite foundation in improving the bearing capacity of the silty fine sand.
基金Project (No.50478090) supported by the National Natural Science Foundation of China
文摘A physical model facility was designed,built,and setup for conducting model tests on a composite foundation in a soil ground.The model tests were carried out on a composite foundation with different combinations of vertical reinforcement elements in the same soil ground.Via the analysis of the collected data the characteristics of the composite foundation with different reinforcing elements were obtained,including the characteristics of load-settlement curves,column stresses,stresses of the inter-column soil,pile-soil stress ratio,and load-sharing ratios of columns and soil.Results from the model tests reveal the mechanism of a composite foundation with different reinforcing elements quantitatively.It is concluded that both a composite foundation with a combination of steel pipe pile and sand column and that with a combination of concrete pile and lime column have a higher bearing capacity than the composite foundation with only sand columns with the same conditions of soil ground and loading.A composite foundation with lime column and sand column embodies no much better performance than that with sand columns only.