高流塑性软土地基土工池基坑支护方案经济性分析

随着城市化进程推进,基坑工程在复杂地质条件施工难度较大,高流塑性软土地基上基坑支护问题备受关注。本文研究不同支护方案对造价、施工效率、安全性及环境等方面的综合影响,为工程实践提供经济合理的支护方案。通过对适用于高流塑性软土地基基坑支护方案进行深入经济性分析,包括成本分析、效益分析和综合经济性评价,验证理论分析实用性,得出各支护方案经济性排序,为类似工程提供参考。

高流塑性淤泥地层中地下连续墙成槽辅助措施

通过深圳地铁11号线连续墙施工实践,从连续墙成槽辅助措施方案比选、外加剂选择、垂直度控制等方面详细介绍了深填海区高流塑性深厚淤泥地层地下连续墙成槽辅助措施施工技术,并对方案提出了优化建议。

钢板桩支护技术在高流塑性软土地基基坑围护中的适用性研究

在高流塑性软土地基的基坑围护中,钢板桩支护方案能有效封堵高流塑性淤泥从坡脚向基底隆起,有效地防止了因此而引起的边坡坍塌。它既安全可靠,又经济快捷。

水泥搅拌桩支护条件下的深基坑土方开挖关键施工技术

广州南沙滨海花园五期住宅项目工程的基坑超大、超深,由于地处淤泥质土层,且工期较紧,因此采取基坑支护、土方开挖同步施工方法。详细介绍了在基坑支护出现大位移情况下,应用土方分块、土方抽条、分离式施工、核心筒处基坑后置等关键技术措施,确保了基坑支护结构的安全性和可靠性,使基坑施工得以顺利完竣。

沿海深厚砂层地质下大直径基桩泥浆护壁及高效入岩施工技术

近年来,大直径桩基施工已成常态,但沿海地区富含淤泥及高流塑性砂层的地质特点不利于桩基施工,易出现塌孔、斜孔、混凝土分层等质量缺陷。以河套深港科技创新合作区东翼-1项目建设,介绍成功改良的泥浆护壁成孔灌注桩工艺,可适用于深厚砂层下的桩基施工;同时介绍大直径桩梅花阵列高效入岩工艺,其相较传统扩孔入岩工艺,在工效提升约2倍的同时,避免了扩孔法易斜孔、易形成锥形底的通病。

Collapse Analysis of Imperfect Subsea Pipelines Based on 2D High-Order Nonlinear Model

To study the collapse of imperfect subsea pipelinos, a 2D high-order nonlinear model is developed. In this model, the large deformation of the pipes is considered by raiaining the high-order nonlinear terms of strain. In addi-tion, the J2 plastic flow theory is adopted to describe the elasioplastic constitutive relations of material. The quasi-static process of collapse is analyzed by the increment method. For each load step, the equations based on the principle of virtual work are presented and solved by the discrete Newton＇s method. Furthermore, finite element simulations and full-scale experiments were preformed to validate the results of the model. Research on the major influencing factors of collapse pressure, including D/t, material type and initial ovality, is also presented.