建筑垃圾再生骨料CFG桩路基加固数值模拟研究

Numerical Simulation of CFG Pile Subgrade Reinforcement Based on Recycled Aggregate of Construction Waste

全国建筑垃圾总量大,利用率低。建筑垃圾经处理后可成为再生骨料,替代天然骨料,制成建筑垃圾CFG桩进行地基加固。文章对苏州建筑拆除垃圾和施工垃圾产量进行调研,其产量均逐年上升。在建筑拆除垃圾中,废弃混凝土占比在50%以上;采用有限元软件对建筑垃圾CFG桩加固地基进行模拟,探究桩长、桩间距等关键性影响因素与沉降的关系。研究结果表明:桩长对路基及地基表面沉降影响很大,当桩体穿过软土层进入坚硬的持力层时,能有效减少沉降;当桩间距为3倍桩径时,路基中心处的地基表面沉降最小;随着桩径的增大,路基表面沉降逐渐减小;随着桩体模量增大,路基及地基表面沉降逐渐减小。经加固的地基满足一级公路一般路段300mm工后沉降的控制要求。

The total amount of construction waste is large,while the utilization rate is low in China. Construction waste after treatment can be recycled aggregate instead of natural aggregate, made of construction waste CFG pile foundation reinforcement. Suzhou building demolition waste and construction waste production in the investigation, and its production are increasing year by year. In building demolition waste, waste concrete are accounted for over 50%; the construction waste CFG pile foundation reinforcement is simulated to explore the relationship between pile length, pile spacing and other key type influence and settlement. According to the results：the length of pile has a great influence on the settlement of subgrade and foundation surface. When the pile passes through the soft soil layer, it can reduce the settlement effectively;; when the pile spacing was 3 times of pile diameter, the minimum at the center of the foundation settlement; with the increase of pile diameter, the subgrade surface settlement gradually decreases with the increase of pile; With the increase of elastic modulus of pile, the settlement of subgrade and foundation surface decreased gradually. The reinforcement of the foundation to meet the general requirements of the first grade highway 300 mm post construction settlement control requirements.