Fall 2002 Ben Schafer thin-walled structures research group

Testing of cold-formed steel beams Jack Spangler Jim Kelly Cheng Yu …most of the CE Grads Sam Phillips Liakos Ariston Tim Ruth Andrew Myers …other CE undergrads Michael Manness, Jr.

Cold-formed steel beams cheng yu Testing –first tests with definitive separation of modes –upper and lower bound flexural capacities –experimental evidence for new design methods FE Modeling –parametric studies –moment gradient effect –influence of restraint Significant design impact Distortional Local

EA/GA and member optimization sam phillips Special : 2 hour “Short Course” Thursday September 26, :00pm to 3:00pm Shaffer Hall Room 101 Evolutionary Computation and Civil/Structural Engineering: A Look Back and a Look Forward Assoc. Prof. Chris Foley Marquette University

collapse of thin-walled members badri hiriyur

collapse of corrugated plastic pipe

generalized beam theory puneet bajpai  Unifies the conventional theories  Better understanding of structural principles  Economical method of analysis  Capability to consider individual buckling modes and select combinations of them  Applicable to linear analysis (First-order GBT), linear stability analysis (General second-order GBT), or bifurcation problems Basic equation of second-order theory : where, E = Young’s modulus, G = shear modulus, = section properties applicable to mode k, = generalized deformation in mode k = distributed load applicable to mode k, = three dimensional array of second-order terms, which includes coupling terms

Stochastic post-buckling jie li, prof. lori graham / c = 1 + a  + b  2 + …, V = c V 0 + (a c V 0 + V 1 )  + (b c V 0 + V 2 )  2 + …

covered wooden bridges dylan lamar (u of ark), erika stoddard, steve buonopane Pine Grove Bridge - Lancaster Co., PA Brown Bridge - Rutland Co., VT

Reliability and advanced analysis steve buonopane, prof. tak igusa Ziemian frame testbed problemStrength at first plastic hinge no correlation to ult. strength Ultimate Strength (via Adv. Anal.) Failure probability estimation

Solver efficiency for reliability and optimization zailong wan, prof. dan naiman, prof. tak igusa {F}=[K t ]{d} [K t ]= building basic geom. basic loads perf. criteria building realization(s) input MASTAN interface deterministic response studyseek efficiency through topology symm. pos-def. sparse topology unchanging

wind on low-rise buildings prof. nick jones Hurricane Loss Reduction Wind and Structural Engineering Initiative through National Institute of Standards and Technology Building and Fire Research Laboratory Gaithersburg, Maryland