Engineering Commons^™

Mode I Fracture Toughness Of Eight-Harness-Satin Carbon Cloth Weaves For Co-Cured And Post-Bonded Laminates, Josh E. Smith

Master's Theses

Mode I interlaminar fracture of 3k 8-Harness-Satin Carbon cloth, with identical fill and weft yarns, pre-impregnated with Newport 307 resin was investigated through the DCB test (ASTM D5528). Crack propagations along both the fill and weft yarns were considered for both post-bonded (co-bonded) and co-cured laminates. A patent-pending delamination insertion method was compared to the standard Teflon film option to assess its applicability to mode I fracture testing. The Modified Beam Theory, Compliance Calibration method, and Modified Compliance Calibration method were used for comparative purposes for these investigations and to evaluate the validity of the proposed Equivalent Stiffness (EQS) method. …

Approximating The Seismic Amplification Effects Experienced By Solar Towers Mounted On The Rooftops Of Low-Rise Industrial Buildings, Peter Luiz Balla

Master's Theses

This thesis investigates the acceleration amplification experienced by solar towers mounted on the rooftops of low-rise industrial buildings during a seismic event. Specifically, this thesis looks to assess the validity of using amplification factors adopted by the ASCE 7-05Minimum Design Loads for Buildings and Other Structures to approximate seismic acceleration amplification for roof-mounted solar towers. To investigate the validity of the ASCE 7-05 amplification factors, this thesis conducts timehistory analyses of three theoretical solar towers mounted on the roof of a case study building. The time history analyses are conducted in the finite element computer modeling program SAP 2000 using …

Weighing The Financial And Sustainable Benefits Of High Performance Structures In Seismically Active Regions, Alia Talina Barajas

Master's Theses

This thesis investigated the potential advantages and disadvantages of high performance structures by comparing the financial and environmental impacts of a performance based four-story office building to one designed to meet minimum code-level requirements.

To generate a comparison, the lateral system of a four-story structure utilizing buckling restrained braced frames was designed to meet code-level requirements per the American Society of Civil Engineers’ Minimum Design Loads for Buildings and Other Structures (ASCE 7-05) and again to meet the immediate occupancy criteria defined by ASCE 41-06 Seismic Rehabilitation of Existing Buildings. The following was then performed:

• Test the structural performance of …

Seismic Rehabilitation Of Steel Moment Frames Vulnerable To Soft-Story Failures Through Implementation Of Rocking Cores, Juan Carlos Sanchez

Master's Theses

During seismic events, inefficient steel moment frame building systems may exhibit soft-story failures. This thesis focuses on development and validation of a seismic retrofit strategy for avoiding soft-story failures in low-rise and mid-rise steel moment frame buildings. The considered retrofit strategy consists of a sufficiently stiff Rocking Core (RC) pinned to the foundation and pin connected to the existing frame. For demonstration purposes, two representative benchmark steel moment frames, which are modified from the three- and nine-story pre-Northridge steel moment frames designed for Los Angeles in the SAC Steel Project, are considered. Finite Element (FE) models of the benchmark buildings …

Seismic Design Manual For Interlocking Compressed Earth Blocks, Nicholas Edwards Kennedy

Master's Theses

Seismic Design Manual for Interlocking Compressed Earth Blocks

Nicholas Edwards Kennedy

This thesis presents a comprehensive seismic design manual to be used to design and construct simple Interlocking Compressed Earth Block (ICEB) structures in seismically active regions. ICEBs are earth blocks made primarily of soil and stabilized with cement. They have female and male stud mechanisms designed to interlock when stacked, eliminating the need for mortar. The blocks can accept reinforcement and grout after they are placed. While ICEB construction is similar to conventional masonry construction, current design code standards for masonry only partially capture the actual behavior of ICEB …

Seismic Rehabilitation Of Steel Concentrically Braced Frames Vulnerable To Soft-Story Failure Through Implementation Of Rocking Cores, Francisco Sanchez-Zamora

Master's Theses

Recent research reports that steel Concentrically Braced Frames (CBFs) (even the code-compliant ones) may be susceptible to soft-story failures during strong earthquakes. Such a failure mode causes catastrophic outcomes and should be definitely avoided in practice. This thesis focuses on development and validation of a seismic retrofit strategy for low-rise and mid-rise steel CBFs vulnerable to soft-story failures. The considered retrofit strategy consists of a sufficiently stiff rocking core (RC) pinned to foundation and connected to the existing frame. For demonstration purpose, two representative benchmark steel CBF buildings, which are the three-and six-story CBFs designed forLos Angelesin the SAC Steel …

Seismic Performance Comparison Of A Fixed-Base Versus A Base-Isolated Office Building, Nicholas Reidar Marrs

Master's Theses

The topic of this thesis is base isolation. The purpose of this thesis is to offer a relative understanding of the seismic performance enhancements that a typical 12-story steel office building can achieve through the implementation of base isolation technology. To reach this understanding, the structures of a fixed-base office building and a base-isolated office building of similar size and layout are designed, their seismic performance is compared, and a cost-benefit analysis is completed. The base isolation system that is utilized is composed of Triple Friction Pendulum (TFP) bearings.

The work of this thesis is divided into four phases. First, …

System Identification Of A Bridge-Type Building Structure, Pablo D. Ramos Jr.

Master's Theses

The Bridge House is a steel building structure located in Poly Canyon, a rural area inside the campus of California Polytechnic State University, San Luis Obispo. The Bridge House is a one story steel structure supported on 4 concrete piers with a lateral force resisting system (LFRS) composed of ordinary moment frames in the N-S direction and braced frames in the E-W direction and vertically supported by a pair of trusses. The dynamic response of the Bridge House was investigated by means of system identification through ambient and forced vibration testing. Interesting findings such as diaphragm flexibility, foundation flexibility and …

Multiplatform Analysis Seismic Evaluation Of A Non-Seismically Detailed Nonlinear Rc Structure Retrofitted With Magneto-Rheological Dampers, Eric R. Lovejoy

Master's Theses

In prior research, the MR damper's dynamic characteristics are typically modeled in the MATLAB/Simulink environment. Creating a structural model with nonlinear material properties, however, may be challenging in the MATLAB/Simulink environment without approximating the material behavior and neglecting effects such as P-∆ or panel zone behavior. More behaviorally accurate models of these structures can be produced using nonlinear finite element analysis tools such as Abaqus, OpenSees or ZuesNL. These analysis tools, however, are not traditionally used to model the complex nonlinear and controllable behavior of MR dampers, nor their associated control algorithms. One solution is to facilitate communication between these …

The Effect Of Sensor Mass, Sensor Location, And Delamination Location Of Different Composite Structures Under Dynamic Loading, Albert Darien Liu

Master's Theses

This study investigated the effect of sensor mass, sensor location, and delamination location of different composite structures under dynamic loading. The study pertains to research of the use of accelerometers and dynamic response as a cost-effective and reliable method of structural health monitoring in composite structures. The composite structures in this research included carbon fiber plates, carbon fiber-foam sandwich panels, and carbon-fiber honeycomb sandwich panels. The composite structures were manufactured with the use of a Tetrahedron MTP-8 heat press. All work was conducted in the Cal Poly Aerospace Structures/Composites Laboratory. Initial delaminations were placed at several locations along the specimen, …