Yeong-il Seo

Yeong-il Seo

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Eurocode Tips & Tutorials Pushover Analysis midas Gen

What are Element Rotation and Hinge Rotation?

Yeong-il SeoApril 25, 2022

What are Element Rotation and Hinge Rotation?


Project Tutorial Design Codes Reinforced Concrete Deflection ACI midas nGen moment redistribution Flexural Resistance continuous beam

How is Moment Redistribution Coefficient Calculated?

Yeong-il SeoApril 19, 2022

Moment Redistribution Coefficient


Project Tutorial Deflection midas Gen Steel Beam continuous beam Beam Deflection cantilever beam deflection limit

Deflection Check of Steel Beam

Yeong-il SeoApril 11, 2022

What is it? - Deflection Limitation


The beam deflection is one of the checks that should be performed for serviceability limit state design. Deflection is the displacement within a structural member under the influence of loads, ignoring the displacements of the rest of the structure.


Figure 1. Deflection Limitation
Figure 2. Suggested Deflection Limits for Structural Elements

News & Trends Reinforced Concrete ACI updated code ACI318-19 ULS Design

ACI 318-19 Updates for ULS Design of Reinforcement Concrete

Yeong-il SeoApril 4, 2022

ACI 318-19 Updates for ULS Design of Reinforcement Concrete


The new ACI318 Code, ACI318-19 is similar with the previous code, ACI318-14 in the basic approach. but in the current documents, there are a number of significant differences.

Through this brief document, you can discover the differences between the two codes, and understand their factors and design concepts.

In this document, the comparison between ACI 318-19 and ACI318-14 Code has 8 classified sections.

1. New rebar material,

2. Minimum reinforcement provisions

3. New reinforcement strain limit

4. Significant updates to shear provisions

5. Hanger reinforcement provisions

6. New equation for Ie

7. Modification of development length provisions

8. Modification of earthquake-resistance provisions.


Also, the specific standards are based on the ACI318M-19 and ACI318M-14 as SI Units for US Codes.


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√ Table of Contents 

Project Tutorial Wind Loads ASCE 7-16 wind pressures

Wind Load as per ASCE 7-16 for the Warehouse with Monoslope Roof

Yeong-il SeoMarch 31, 2022

Wind Load as per ASCE 7-16


Information of Example Model

This is an explanation how to input wind load data in the warehouse with monoslope roof.

Information of the example model is given as follows.

Figure1. Warehouse Example Model

 Figure 2. Warehouse Roof Example Model
Table 1. Wind Load Data Informations
√ Table of Contents 

News & Trends flat slab design flat slab beam element

An Understanding of Structure in 2-Way Slab System

Yeong-il SeoMarch 22, 2022

Structure in 2-Way Slab System


The Building Structural Standard defines a two-way slab system as a concrete slab system in which two rebars are arranged in two directions regardless of the presence or absence of a beam that transmits a load to a column'. Also, in ACI 318, this is expressed as ‘slab systems reinforce flexure in more than one direction, with or without beams between supports’. Therefore, a two-way slab system refers to a slab system in which reinforcing bars are arranged for bending in two or more directions regardless of the presence or absence of beams in columnar rows'. Typical types of two-way slab systems commonly used today include two-way slabs with beams, flat plates, flat slabs, and waffle slabs.


Figure1. Typical Types of 2-Way Slab

√ Table of Contents 
You can download the full contents at the end of this page.

Tips & Tutorials Nonlinear Analysis Nonlinear Elements Analysis Manual for Midas/Gen

What is a Nonlinear Analysis?

Yeong-il SeoMarch 16, 2022

What is Geometric Nonlinear Analysis?


Time History Analysis Tips & Tutorials Response Spectrum Buckling analysis Analysis Manual for Midas/Gen

MIDAS/Gen Analysis Options - Part 2.

Yeong-il SeoMarch 7, 2022

MIDAS/Gen Analysis Options - Part 2.


Tips & Tutorials Damping Link Elements free vibration linear analysis Analysis Manual for Midas/Gen

MIDAS/Gen Analysis Options - Part 1.

Yeong-il SeoFebruary 28, 2022

MIDAS/Gen Analysis Options - Part 1.


You can download E-book for MIDAS/Gen Analysis Options - Part 1, After filling out the form at the end of this page.

Prestressed Concrete PSC Time Dependent Losses News & Trend Creep and Shrinkage Analysis Manual for Midas/Gen Post-Tensioned Concrete Instantaneous Losses Anchorage Slip Prestressed Concrete Analysis

Pre-Stressed/Post-Tensioned Concrete (PSC) Analysis

Yeong-il SeoFebruary 21, 2022

Pre-Stressed Concrete (PSC) Analysis


Project Tutorial Analysis Manual for Midas/Gen Design Conditions

Solution for Unknown Loads Using Optimization Technique

Yeong-il SeoFebruary 14, 2022

Solution for Unknown Loads Using Optimization Technique


News & Trends Thermal Stress convective heat transfer Analysis Manual for Midas/Gen Pipe Cooling Accumulated Temperature Thermal Conductivity Heat Source Concrete Structure Heat of Hydration Analysis

Heat of Hydration Analysis

Yeong-il SeoFebruary 7, 2022


In a certain concrete structure with considerable mass or where a construction progresses rapidly with a number of construction joints, the rate and amount of heat generation due to hydration are important. Non-uniform thermal expansion and contraction due to heat of hydration and cooling of concrete accompanied by changing constraints create undesirable stresses. The stresses may cause detrimental cracking in the concrete, thereby reducing its strength and durability.


Heat of hydration analysis thus becomes important when casting mass concrete structures. It enables us to predict and control temperature and stress distribution within a structure to avoid potential problems. Mass concrete structures requiring heat of hydration analysis depend on their dimensions, shapes, cement types and construction conditions.


In practice, hydration analyses are normally carried out for slabs or mats in excess of 800~1000mm in thickness and walls confined at bottom in excess of about 500mm. Surface cracking may develop initially due to the temperature difference between the surface and center. Through-cracks can also develop as a result of contraction restrained by external boundary conditions in the cooling process of high heat of hydration.


The heat of hydration analysis is largely classified into several sub-analyses. It entails temperature distribution analysis for conduction, convection, heat source, etc.; change in modulus of elasticity due to curing and maturity; and stress analysis for creep and shrinkage. The following outlines the various components affecting the analysis.



1. Heat Transfer Analysis

2. Thermal Stress Analysis

3. Procedure for Heat of Hydration Analysis

Structure Insight Rigid End Offset boundary condition elastic boundary element Degree of Freedom Element End Release Spring Support

What are Boundary Conditions?

Yeong-il SeoJanuary 27, 2022


Boundary conditions represent the status of connections between the structure and neighboring structures such as foundations. Boundary conditions are distinguished by nodal boundary conditions and element boundary conditions.

Nodal boundary conditions:

The constraint for the degree of freedom
Elastic boundary element (Spring support)
Elastic link element (Elastic Link)

Element boundary conditions:

Element end release
Rigid end offset distance (Beam End Offset)
Rigid link


Project Tutorial Construction Stage Analysis Time Dependent Material Properties Creep and Shrinkage Analysis Manual for Midas/Gen

Construction Stage Analysis Reflecting Erection Sequence

Yeong-il SeoJanuary 20, 2022



A building structure is typically constructed floor by floor in the case of a reinforced concrete structure or often constructed several floors at a time in the case of a structural steel structure. Even on the same floor, different parts are constructed at different stages.

A typical structural analysis entails applying the loads to the completed structure at once. This results in significant discrepancies as the scale of the building increase, especially as the number of stories increases. Regardless of the type of construction, construction dead loads on a particular floor are typically acting on the structure without the presence of the upper floors during the construction. This actually results in completely different column shortenings from the analysis results based on the “full loading on the completed structure”.  The change of strength gain, creep and shrinkage in the case of reinforced concrete construction compound the discrepancies. MIDAS/Gen enables the engineer to account for the change of geometries and time-dependent material properties during and after the construction.

Each temporary structure at a particular stage of construction affects the subsequent stages. Also, it is not uncommon to install and dismantle temporary supports during construction. The structure constantly changes or evolves as the construction progresses with varying material properties such as modulus of elasticity and compressive strength due to different maturities among contiguous members. The structural behaviors such as deflections and stress re-distribution continue to change during and after the construction due to varying time-dependent properties.

Since the structural configuration continuously changes with different loadings and support conditions, and each construction stage affects the subsequent stages, the design of certain structural components may be even governed during the construction. Without such construction stage analysis, the conventional analysis will not be reliable.







Tips & Tutorials Tension-Only Elements Truss Elements Compression-Only Elements Analysis Manual for Midas/Gen Two-Dimensional Axisymmetric Element Element Stiffness Data Wall Element Axisymmetric Element Plane Element Solid Element

Element Stiffness Data

Yeong-il SeoJanuary 13, 2022


Structure Insight Tension-Only Elements Truss Elements Compression-Only Elements Analysis Manual for Midas/Gen Two-Dimensional Axisymmetric Element

What are Important Aspects of Element Selection?

Yeong-il SeoJanuary 6, 2022


Tips & Tutorials Cable Elements Tension-Only Elements Truss Elements Compression-Only Elements Analysis Manual for Midas/Gen Two-Dimensional Plane Strain Element Two-Dimensional Axisymmetric Element Element Forces

Important Considerations of Element Types

Yeong-il SeoDecember 30, 2021


Project Tutorial Tips & Tutorials Structural Design Cable Elements Tension-Only Elements Truss Elements Nonlinear Elements Compression-Only Elements

Design Method of Structures Using Cable and Truss Elements

Yeong-il SeoDecember 23, 2021


Project Tutorial Structure Insight High-rise building Low-rise building Construction Stage Analysis Structural Design Column Shortening

Applications of Construction Stage Analysis in Structural Design

Yeong-il SeoDecember 16, 2021

Construction Stage Analysis at Low or Middle Building


News & Trends Seismic Analysis Seismic Isolation Lead Rubber Bearing LRB Seismic Isolator Seismic Isolating System Friction Pendulum System

How to Perform Seismic Isolation Analysis?

Yeong-il SeoDecember 9, 2021


Tips & Tutorials Basement Modeling Underground Analysis Underground Modeling Basement Analysis

Modeling Guide for Basement Floors

Yeong-il SeoDecember 2, 2021