GROUP 是一款知名的软件，用于分析承受轴向、侧向及扭转组合荷载作用下的群桩行为。该程序旨在计算荷载（包括竖向力、侧向力和最多三个正交轴向的倾覆力矩）在桩群中的分布情况，这些荷载施加于刚性或柔性桩帽上的多个位置。此外，GROUP 还能估算模型中各根桩及桩帽的侧向和轴向位移。
该程序在内部生成土体的非线性响应，具体表现为：轴向荷载下的 t-z 和 Q-w 曲线、侧向荷载下的 p-y 曲线以及扭转荷载下的 T-q 曲线。求解过程需要进行迭代，以适应桩群模型中各根桩的非线性响应特性。GROUP 程序求解各根桩在组合荷载作用下的非线性响应，并确保施加的外部荷载与各桩顶反力之间的变形协调及力平衡。
可用版本: 2022.x , …
Ensoft Group Flexible Cap 2022.12.10
Selected Features
p-y Curves
Various built-in p-y curves including:
- Clay
- Soft Clay (Matlock)
- Reese Stiff Clay with or without free-water
- API Soft Clay With User-defined J
- Modified Stiff Clay without free-water
- Modified soft clay with initial K
- Sand
- Liquified sand (Rollins).
- Liquified sand (Hybrid Model).
- Reese Sand
- API O’Neil Sand
- Elastic subgrade
- Silt (Cemented c-φ)
- Reese Weak Rock
- Strong rock (Vuggy Limestone)
- Massive Rock
- User-input p-y curves
- Elastic Subgrade
- Piedmont Residual
- Loess
Pile Sections
User defined piles with circular, rectangular, and/or wide-flange sections, with option to include nonlinear flexural stiffness for standard reinforced concrete sections for complex composite sections with structural steel inserts.
- Elastic
- Circular (hollow or full)
- Rectangular
- Custom widge flange
- Predefined AISC sections from built-in library
- User defined sectional properties
- Nonlinear
- Circular section with or without rebar reinforcements
- Circular sections with casing
- Circular steel tubes
- Predefined AISC sections from built-in library
- Prestressed square sections
- Presstressed octagonal sections
- User defined EI
Loading
Accepts combined loadings (axial + lateral) with load factors and with ability to compute maximum and minimum envelops for load cases and load combinations.
Users may specify concentrated loads (at any position) at the pile cap and/or distributed lateral loads (using local or global axes) along the length of any pile(s).
Includes option to use cyclic model for soil p-y curves where available.
Soil Movement
The user is able to input a profile of soil movements versus depth as additional loading on the pile. The movements of the soil may be produced from any action that causes soil movements, such as those due to slope instability, lateral spreading during earthquakes, and seepage forces.
Analysis
Option to use multiple cores for considerable reduction in computing time on large models.
Able to consider push-over analysis.
Improved algorithms to enhance solution accuracy and convergence in nonlinear problems.
Considers lateral soil resistance against embedded pile caps and optionally specify reduction factor on axial capacity of each individual pile.
Toggle computation of required unit side friction and top and bottom of each layer along with a unit tip resistance.
May optionally compute the foundation stiffness matrix based on equivalent elastic stiffness.
Output
Individual pile bending moment, shear force, mobilized sectional properties, curvature of piles under each load case, and more are outputted for each example.
Optionally print out a text file (response file) with equivalent nonlinear springs along the pile, which is useful for performance of complete soil-structure interaction analyses using other structural software.
p-y curves may be automatically generated by the program and printed for review. Points of internally generated p-y curves can be requested for output according to user-defined levels of deflections.
Export loading, pile group layout, or resulting graphs directly to pre-fromatted spreadsheet (for MS-Excel).
Modeling and Model generation
Quickly create models from predefined templates using rectangular or circular pile groups.
Optionally import data from
- LPILE model files,
- EnCPT generated soil layers
or import pile layout and/or loading directly from MS-Excel files.
Consider up to 1000 vertical and/or battered piles in the same pile group analysis. Each pile can have different cross-section and flexural stiffness in orthogonal directions.
Boundary Conditions
Specify conditions pile-cap connection as
- Fixed
- Pinned
- Elastically restrained with a user-defined rotational spring stiffness
Documentation
GROUP comes equipped with electronic copies of detailed User’s Manual and a Technical Manual, as well as multiple examples and input files. Download and view the examples and input files with GROUP running in Demo mode.
More Information in English: Ensoft Group Flexible Cap 2022.12.10