摘要
为进一步研究复合桩加固液化土地基机理,制备未加固、碎石桩与钢管桩、水泥土桩与钢管桩复合加固三种地基模型,模拟地震荷载,进行振动台试验。通过数据采集系统采集三种模型数据,整理出地基在振动过程中不同埋深处的超静孔隙水压力时程曲线和土压力时程曲线。结果表明:未加固、水泥土桩与钢管桩复合加固模型超静孔隙水压力增长到峰值7 kPa左右,保持不变到试验结束,碎石桩与钢管桩复合加固达到峰值为5 kPa左右,试验结束时减小到2.5 kPa左右,其中碎石桩起到消散超静孔隙水压力的作用;未加固、水泥土桩与钢管桩复合加固的土压力达到峰值105 kPa左右,之后减小了35 kPa左右;碎石桩与钢管桩复合加固地基模型土压力值与峰值相等为110 kPa左右,土体强度较高,复合地基承载能力较大。表明采用碎石桩与钢管桩复合加固不仅有效的抵抗土体液化,而且还提高了复合地基的承载能力,为碎石桩与刚性桩复合加固液化土在实际工程中的推广应用起到参考作用。
In order to study the mechanism of using composite pile to reinforce liquescent soil foun-dation, three models, including un-reinforced foundation, foundation reinforced by gravel pile and steel pipe pile, foundation reinforced by cement pile and steel pipe pile were prepared, and simula-ted seismic load was applied by the shaking table test. Pressure-time curve of excess pore water in different depth and pressure-time curve of earth in different depth were sorted out from the data col-lected by the data acquisition system in the three models during the vibration of foundations. The test results show that the pressure of excess pore water of the un-reinforced and foundation reinforced by cement pile and steel pipe pile was increased to the peak around 7 kPa and the pressure remained 7 kPa until the end of the test. The pressure of excess pore water of the foundation reinforced by gravel pile and steel pipe pile was increased to the peak around 5 kPa and it was reduced to about 2. 5 kPa at the end of the test. The gravel pile plays a role of dissipating the pressure of excess pore water. The earth pressure of the un-reinforced and foundation reinforced by cement pile and steel pipe pile was increased to the peak around 105 kPa, then reduced by about 35 kPa. The earth pres-sure of foundation reinforced by gravel pile and steel pipe pile is equal to the peak about 110 kPa.Soil strength and the bearing capacity of composite foundation are high. Therefore, using the founda-tion reinforced by gravel pile and steel pipe pile can effectively resist soil liquefaction and improve foundation bearing capacity. The research plays a reference role for the promotion of gravel pile and rigid pile reinforced liquefied soil in engineering.
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2014年第4期817-822,共6页
Journal of Guangxi University（Natural Science Edition）
基金
国家自然科学基金资助项目(50578104)
山西省交通厅科技项目(10-1-06)
关键词
复合桩
振动台
超静孔隙水压力
土压力
液化土
composite pile
shaking table
pressure of excess pore water
earth pressure
liques-cent soil
