modify wiki

wiki/concepts/Direct Time Integration Methods.md

@@ -8,7 +8,7 @@ aliases:
   - direct integration
   - Newmark method
 created: 2026-05-28
-updated: 2026-05-28
+updated: 2026-05-29
 address: c-000014
 tags:
   - concept
@@ -21,10 +21,18 @@ related:
   - "[[Nonlinear Newmark-Beta Integration]]"
   - "[[Dynamic Buckling Analysis]]"
   - "[[Finite Element Eigenproblem Solvers]]"
+  - "[[Abaqus Analysis Procedures]]"
+  - "[[Abaqus Explicit Analysis Efficiency Techniques]]"
+  - "[[Abaqus Eulerian and Particle Methods]]"
+  - "[[Beam and Frame Finite Elements]]"
+  - "[[Bar and Truss Finite Elements]]"
 sources:
   - "[[Finite Element Procedures]]"
   - "[[MITC Study Notes]]"
   - "[[Dynamic-Buckling-Analysis-of-Shell-Structures-using-Finite-Element-Method]]"
+  - "[[Abaqus Theory Manual]]"
+  - "[[A-First-Course-in-the-Finite-Element-Method|A First Course in the Finite Element Method]]"
+  - "[[Abaqus-Analysis-User-s-Guide-Volume-II|Abaqus Analysis User's Guide Volume II]]"
 ---
 
 # Direct Time Integration Methods
@@ -41,6 +49,12 @@ The MITC study notes add a focused nonlinear Newmark-beta derivation: Newton ite
 
 The dynamic buckling thesis uses time-dependent axial compression as the loading context. It connects dynamic response, natural frequency, and buckling instability boundaries rather than treating time integration as a standalone transient solve.
 
+[[Abaqus Analysis Procedures]] places direct integration inside the broader procedure choice: implicit dynamics, explicit dynamics, modal dynamics, and coupled transient field analyses each carry different stability, increment, and convergence requirements.
+
+[[A-First-Course-in-the-Finite-Element-Method|A First Course in the Finite Element Method]] adds the elementary matrix-dynamics path: spring-mass equations, lumped and consistent mass matrices for bars, beams, trusses, frames, plane elements, axisymmetric elements, and solids, plus central difference, Newmark, Wilson, and transient heat-transfer examples.
+
+[[Abaqus-Analysis-User-s-Guide-Volume-II|Abaqus Analysis User's Guide Volume II]] expands the production procedure choices: implicit direct integration, explicit dynamic analysis, direct-solution steady-state dynamics, modal dynamics, subspace steady-state dynamics, response spectrum, and random response analysis.
+
 ## Why It Matters
 
 Time integration choices control stability, phase accuracy, numerical damping, and computational cost. Explicit methods can be efficient for very small stable time steps; implicit methods are more expensive per step but can support larger steps and nonlinear equilibrium iterations.
@@ -51,9 +65,16 @@ Time integration choices control stability, phase accuracy, numerical damping, a
 - [[Nonlinear Finite Element Analysis]] couples time integration with nonlinear iteration.
 - [[Nonlinear Newmark-Beta Integration]] is the specific implicit nonlinear dynamics workflow extracted from the MITC notes.
 - [[Finite Element Heat Transfer and Field Problems]] uses related transient integration ideas for first-order field equations.
+- [[Abaqus Analysis Procedures]] connects transient integration to Standard/Explicit procedure selection.
+- [[Abaqus Explicit Analysis Efficiency Techniques]] covers mass scaling, subcycling, and steady-state detection around explicit integration.
+- [[Abaqus Eulerian and Particle Methods]] uses explicit time integration for Eulerian, DEM, and SPH workflows.
+- [[Beam and Frame Finite Elements]] and [[Bar and Truss Finite Elements]] provide simple structural examples for mass-matrix construction.
 
 ## Sources
 
 - [[Finite Element Procedures]]
 - [[MITC Study Notes]]
 - [[Dynamic-Buckling-Analysis-of-Shell-Structures-using-Finite-Element-Method]]
+- [[Abaqus Theory Manual]]
+- [[A-First-Course-in-the-Finite-Element-Method|A First Course in the Finite Element Method]]
+- [[Abaqus-Analysis-User-s-Guide-Volume-II|Abaqus Analysis User's Guide Volume II]]