Santa Clara University

Sustainable Engineering Designs 2005

The following are senior design projects with an emphasis on sustainable engineering.

Human-Powered Utility Vehicle: Designed for Mass Production for the People of El Salvador
William G. Arroyo, Cody A. Bedell, Robin B. Bell, Andrew J. Leland, Charlie A. Leone, Francisco J. Prado Cervantes
Advisor: Timothy Hight

Summary:
The project team chose to develop a human-powered utility vehicle to be used in small El Salvadoran towns as a primary means of transporting people and cargo.

The project was sponsored by the Centro Salvadoreno de Tecnologia Apropriada (CESTA), a non-profit organization based in El Salvador, working to promote sustainability and improve the country’s way of life. Through customer need surveys and regular contact with the people from CESTA, the design of the vehicle was tailored to meet the customer’s needs, specifications, and requirements.

The final design of the human-powered vehicle is a three-wheeled vehicle with one wheel at the rear and two at the front. The rear portion of the vehicle is composed of a 24” or 26” mountain bicycle frame. Attached to the bicycle frame is a steel cargo container frame in the shape of a box that has a bicycle headset attached on opposite sides.

The project had the unique challenge of being designed for mass production, and the goal was to manufacture the vehicle using only the tools and parts available in El Salvador. Using used bike parts obtained through Pedals for Progress, the HPUV can be manufactured for under $150.00.

The Sustainability of Mesh Anchorage for Straw Bale Walls
Andrew C. Parker
Advisor: Mark Aschheim

Summary:
This project examines the strength of various mesh anchorage details to further the objective of designing durable, earthquake-resistant straw bale structures. Attention is also given to the potential for the deterioration of the mesh and/or staple over time.

Seismic Susceptibility and Sustainability of Mixto Structures in El Salvador
Shannon Flanagan, John Harlander, Chris Pitt
Advisor: Mark Aschheim

Summary:
In 2001, two large earthquakes destroyed 165,000 homes and damaged another 110,000 homes in El Salvador. The earthquakes created a situation in which 60% of the population was either homeless or living in substandard housing conditions.

Homes built using an improved clay brick technology known as “Mixto”, performed reasonably well in the 2001 earthquakes, with fewer than 12% of the total units damaged. Mixto involves fired clay brick wall infill sections confined within reinforced concrete beams and columns, where the concrete is placed after the bricks are laid. This project focused on three primary aspects of improving Mixto structures.

Seismic Roof Designs in El Salvador with Investigation of Sustainable Bamboo I-Joists
Mark Folgner
Advisor: Mark Aschheim

Summary:
The project developed bamboo roofing systems for Mixto (confined masonry) houses in El Salvador and manufactured bamboo I-joists to provide a sustainable alternative to manufactured timber I-joists. The goal of the project was to design a sustainable roofing structure using Bamboo that could replace the steel channels currently imported from Guatemala and to provide seismic resistance to the roof systems.

Sustainable Solar Power Solution for the Fresh Water Infrastructure of Isla Zacatillo
Mike Downing, R. David Hague, Nick Lochridge, Steve Perry, and Brian Edlefsen
Advisor: Jorge Gonzalez-Cruz

Summary:
The island community of Isla Zacatillo, located a few miles offshore of El Salvador, currently relies on a freshwater delivery infrastructure that operates on electricity. The system consists of a freshwater collection cistern and a 10,000 gallon tank. Water is pumped from the cistern to the tank and then delivered to the 300 person community. The system is prone to frequent inoperability due to electrical problems. The team designed a replacement with the following core characteristics: reliability, low maintenance, sustainability, and redundancy.

Septic Tanks/Stabilization Ponds for a Rural Community: Isla Zacatillo
Wastewater System for the Community of La Playona
Santiago Cruz-Roveda
Advisor: Steve Chiesa

Summary:
La Playona is a small community located on Isla Zacatillo, a small island off the coast of El Salvador. Currently, there is no wastewater disposal system for this community; the 300 people living in this community use outhouses or holes in the ground. The student designed a wastewater system that is gravity-fed and easy to maintain. The system was designed to last 15 years or until newer technology replaces the system.

Rural Community Water Distribution System
Gravity Fed Water System
Victor Lopez
Advisor: Edwin Maurer

Summary:
Potable water is available to only about 28% of people who live in the rural communities of La Isla/La Junta, Nicaragua. The student designed a gravity flow water distribution system to move water from a natural spring to the community. A main water line travels from the natural spring to a storage tank, and a distribution network moves the water from the storage tank to the individual faucets. The system was designed to provide water to the 36 homes in the community – allowing for personal washing, drinking, cooking, and domestic animal needs.

Water Supply Development: Isla Zacatillo
Nathan Martel
Advisor: Edwin Maurer

Summary:
In El Salvador, 95% of freshwater sources are contaminated with E. coli and other coli forms. The student studied the water needs of the people of Isla Zacatillo and then investigates rainwater harvesting as a sustainable solution to easing Isla Zacatillo’s water supply problems. The report studied rainfall patterns of the region, roof material and runoff, gutter sloping, downspout sizing, and cistern sizing and materials.