摘要
研究目的:既有铁路增建二线,受行车运营干扰、施工场地及接触网净空高度等限制,软土地基加固处理难度较大。因此,需要研究一种合理的地基加固方法,不仅能够满足场地受限要求及路基沉降控制要求,而且能够保证既有线运营安全。研究结论:布袋加筋注浆成桩法是注浆技术、土工织物、加筋材料综合应用而成的一项新技术。通过研究,得出以下结论:(1)土工布袋的隔离作用使得浆液通过膨胀布袋达到压密土体的目的,加筋注浆管作为注浆通道简化了施工工序,同时极大的增强了桩体的抗剪强度、抗变形能力;(2)施工采用普通旋转钻机作业,且可根据场地适当调整,占地范围小,降低对施工场地和净空高度的限制要求;(3)浆液采用孔底返浆法施工,由下至上,分节注入,同时可多次补浆,能较好保证桩体成桩质量;(4)采用布袋加筋注浆桩既可保证桩身抗剪强度及承载能力,又能适应场地及空间限制,可在软土地基加固工程中推广应用。
Research purposes： During the rebuilding lane close to existing railway, restricted by the driving interference and limitations of construction site and catenary headroom, reinforcement of soft ground is a difficult problem. Therefore, it needs a rational technology which can not only able to meet the limited space and subgrade settlement control requirements, but also ensure the existing railway safely operate. Research conclusions：Bag reinforced grouting pile is a new technology using a combination of grouting technology, geotextile fabric and reinforced materials. The main advantages are followings ： （ 1 ） The isolation of geotextile bag can make slurry to expand bag and compact soil. Reinforced grouting pipe as grouting channel not only simplifies the construction process ,but aslo greatly enhances the shear strength and resistance deformation. （2）Construction uses the ordinary rotary drilling rig which has many advantages, such as appropriate adjustment according to the site, small footprint range, lower limitations of space and headroom. （3）The method of returning slurry from the hole bottom is adopted to construction by sub - section injection, repeatedly supplementary slurry, which can better ensure the pile quality. （4）The test results show that the bag reinforced grouting pile can not only ensure the shear strength and capacity, but also adapt the limitations of construction site and space and headroom, it can be widely applied in the reinforcement of soft ground.
出处
《铁道工程学报》
EI
北大核心
2014年第12期33-36,共4页
Journal of Railway Engineering Society
关键词
布袋加筋注浆桩
软基加固
既有铁路
场地和净空限制
孔底返浆法
bag reinforced grouting pile
reinforcement of soft ground
existing railway
limitations of space and headroom
method of returning slurry from the hole bottom
