MODELOS LINK SAP2000 Problem 6 004

Software Verification PROGRAM NAME: REVISION NO.:

SAP2000 1

EXAMPLE 6-004 L INK – HOOK ELEMENT PROBLEM DESCRIPTION In this single degree of freedom example, a frame element is fixed at one end and connected to a grounded hook element at the other end. The initial opening in the hook is 0.04 inch. A temperature drop of 100 °F is applied to the frame element. The displacement at joint 1 and the axial force induced in the link and frame elements by the temperature drop are compared with hand calculated results. The model is created in the XZ plane. Only the Uz degree of freedom is active for the analysis. The hook element is modeled as a single-joint link element at joint 1. This means that one end of the hook element is connected to the ground and the other end is connected to joint 1. The hook element is oriented such that its  positive local 1 axis is parallel to the positive global Z axis. This is the default orientation of single joint link elements. Only U1  degree of freedom properties are defined for the hook element. When closed, the stiffness of the hook element is 5,000 k/in. The analysis is performed using static nonlinear load cases.

GEOMETRY, PROPERTIES AND L OADING

Frame element fixed at its top end and connected to hook element at its bottom end. Total length of frame element is 100"

2 1

        "         0         0         1

Initial opening of hook element is 0.04"

Z

1 X

Single-joint (zero-length) link element (hook) with tension stiffness defined for the U1 degree of freedom

Link Properties (Gap U1 DOF) Linear Ke = 0 k/in Linear Ce = 0 k-se k-sec/in c/in Nonlinear K = 5,000 k/in Nonlinea onlinearr Open Open = 0.04 in Frame Frame Material Propert Properties ies E = 29,00 29,000 0 k/in2 α = 0.0000065 /°F Frame Section Properties  A = 10 in2 Loading Temperature Drop = 100 °F  Ac  Activ tive Degree rees of Free reedom Uz

EXAMPLE 6-004 - 1

Software Verification PROGRAM NAME: REVISION NO.:

SAP2000 1

TECHNICAL FEATURES OF SAP2000 TESTED  Hook element links  Force-controlled nonlinear static analysis  Frame temperature loads

RESULTS COMPARISON Independent results are hand calculated using standard thermal expansion formulas.

Output Parameter

SAP2000

Independent

Percent Difference

Uz displacement at joint 1 in

0.04918

0.04918

0%

Link axial force kips

45.886

45.886

0%

Frame axial force kips

45.886

45.886

0%

COMPUTER FILE : Example 6-004 CONCLUSION The SAP2000 results show an exact comparison with the independent results.

EXAMPLE 6-004 - 2

Software Verification PROGRAM NAME: REVISION NO.:

SAP2000 1

H AND C AL CULATION

EXAMPLE 6-004 - 3

Software Verification PROGRAM NAME: REVISION NO.:

SAP2000 1

EXAMPLE 6-004 - 4

Software Verification PROGRAM NAME: REVISION NO.:

SAP2000 1

EXAMPLE 6-004 - 5