The Science and Economics of Concrete Presented by © Copyright 2016. Project Cornerstone, Inc. Workshop Sponsors Materials Donors: CalPortland Superior Ready Mix Who is Project Cornerstone? 2nd Most Consumed Commodity by Volume …in the World! #1 Commodity Consumed: Water #2 Commodity Consumed: Construction Aggregate/ Concrete/Asphalt Bridges Rocks Homes Schools Roads Construction Aggregates SAND ● GRAVEL ● CRUSHED STONE Sand and Gravel (Alluvial Sources: riverbeds) Crushed Stone (Stadium/Poway Conglomerate, Peninsula Range and the Santiago Peak Formation) ESS2.A: EARTH MATERIALS AND SYSTEMS How do Earth’s major systems interact? EXAMPLE : WHERE DO YOU FIND SAND AND HOW WAS IT CREATED? Beach – weathering from waves River– alluvial/alluvial fan, weathering from water Desert – sand dunes, weathering from wind ESS3.A: NATURAL RESOURCES How do humans depend on Earth’s resources? DEMAND FOR CONSTRUCTION AGGREGATE Construction Aggregate Uses Other Private Railroads Private Roads Facilities 1% 3% 2% Public Highways, Streets, and Commercial Transit Buildings Other Public 26% 17% Facilities 3% Residential Buildings Water & Sewer 34% 5% Hospitals & Schools Construction 2% Other Public aggregate forms Buildings Utilities the physical foundation 3% 4% of our societal infrastructure. Construction Aggregate Uses Increasing Demand Every person in San Diego County consumes approximately 5.4 tons of aggregate per year. A family of four would need 22 tons per year or almost a { full truck load of material. } San Diego County’s population is expected to grow, putting additional pressure on aggregate supplies. Economic Principle Supply and Demand History: 2.4.2 & 2.4.3 San Diego County Aggregate Production vs. Demand 25 20 15 10 5 Million Tons Million 0 Aggregate Production Aggregate Consumption @ 5.4 tons per capita Source: Population: California Department of Finance; Demand: Dept of Conservation OFR 94-08; Production: California Department of Conservation San Diego County Construction Aggregate Quarries 2012 San Diego County Construction Aggregate Quarries 2030 San Diego is Rich with Resource Reasons for Aggregate Shortage • Number of quarries are decreasing due to resource d e p l e t i o n • Approval of conflicting land uses near mine sites • Known mineral resources not protected at local level • Permitting process has high risk and cost, and is time prohibitive Addressing the Shortage • Continue to Import Aggregate (Primarily Sand) • Recycle • Permit Additional Local Reserves Importing Materials from Great Distances Import Areas Are Also in Short Supply Source: Clinkenbeard, John, P., “Aggregate Sustainability in California.” Department of Conservation, California Geological Survey. 2012. 167 = Permitted Reserves Remaining; 1014 = 50 year demand Impacts from Importing Increased Transportation Costs High Bulk – Low Value --- Cost is $0.20/ton/mile High paying jobs are sent offshore or out of County Increased air pollution and greenhouse gas emissions Increased road congestion (VMT) and maintenance costs Reduces impetus to develop resources locally and eliminates competition Impacts on Greenhouse Gases Based on a Projected 19 million tons/yr of Aggregate Needed for 2010-2030 An all local supply results in nearly 4 times less CO2 than importing the entire supply. 250000 200000 Truck (Imported) 219,203 150000 Truck (Local) 100000 115,370 50000 56,993 27,000 Emissions Emissions 0 2 a. All Local b. Local and c. All (metric (metric tons) CO Supply Imported Imported Supply Supply a. All 19 million tons of aggregate supplied by local mines via truck. b. Local mines supply 9 million tons via truck; 10 million tons imported via truck. c. All aggregate imported via truck. Source: San Diego Region Aggregate Supply Study. SANDAG. Jan 2011. Recycled Materials Helps conserve limited resources Reduces materials sent to landfills However… Limited in supply and use Recycled aggregates cannot be used for all construction projects. If all concrete & rubble were recycled, it would represent only 5-10% of total aggregates produced. Source: Recycling Today & USGS Fact Sheet FS-181-99, February 2000. Permitting Local Sites Lower Costs for Aggregate Reduced Cost for Construction Projects Lower Greenhouse Gas Emissions Improved Air Quality Reduced Traffic Congestion Reduced Road Maintenance Costs And… High paying jobs stay local! ESS3.C: HUMAN IMPACTS ON EARTH SYSTEMS How do humans change the planet? History: 3.5.1, 3.5.3, 8.6.1 EXAMPLES OF HUMAN IMPACT •Externalities from deciding not to permit local operations •Recycling • Benefits of reclamation Mining is a Transitional Land Use History of Concrete Concrete Fun Facts Hoover Dam contains enough concrete to pave a two lane road between Seattle and Miami. (4.4 million cubic yards) The amount of concrete used worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminum combined. In the last 3 years, China has used more concrete than the US did over the past 100 years. http://www.dailykos.com/story/2014/06/13/1306854/-China-has- consumed-more-concrete-in-3-5-years-than-United-States-did-in-100- years-says-Bill-Gates Concrete Ingredients Photo by David Iliff. Pont du Gard, aqueduct South of France The Romans were the first to realize c. 40-60 AD the potential of concrete. Photo by Wolfgang Staudt. History Standards 6.7: Students analyze the geographic, political, economic, religious, and social structures during the development of Rome. 3. …how the empire fostered economic growth and trade routes. 8. Discuss the legacies of roman art , architecture, engineering and science. 7.1: Students analyze the causes and effects of the vast expansion and ultimate disintegration of the roman empire. 1. Study the early strengths and lasting contributions of roman art and engineering. Helpful Resources 300 BC Romans used slaked lime a volcanic ash called pozzuolana, found near Pozzouli by the bay of Naples. They used lime as a cementitious material. Pliny reported a mortar mixture of 1 part lime to 4 parts sand. Vitruvius reported a 2 parts pozzolana to 1 part lime. Animal fat, milk, and blood were used as admixtures 193 BC of PorticuHouse s Amelia made of bound stones to form concrete 200 AD The Pantheon After 400 AD The art of concrete was lost after the fall of the Roman Empire http://www.auburn.edu/academic/architecture/bsc/classes/bsc314/timeli ne/timeline.htm http://cdn.history.com/sites/2/2013/03/Mankind-Rome-Infographic.jpg http://activealert.blogspot.com/2011/05/essay-influence-of-concrete-on.html Roman Concrete Resources www.romanconcrete.com Roman Concrete Lime concrete = caementis ("rocky stuff"). Lime mortar mixed with aggregate, it was mostly aggregate. Caementi were small, sharp stones that ranged from broken pebbles to fist sized rocks. Oddly it is from the Latin caementis that we derive the modern English word cement, which we often confuse with concrete. The term concrete, though derived from the latin concretus (meaning "brought together" or "congealed"), was never used by the Romans to describe the material. They most often referred to is as: opus caementicium Concrete Changed How Roman’s Built Roman concrete used an important additive called pulvis puteolis, pozzolanic soil or poweder. (Puteoli being the ancient Latin name for the modern Italian city of Puzzuoli, near Vesuvius). Pozzolan was mixed with the caementis to make it either impervious to or to allow it to set under water. Romans also discovered that pulvis puteolis also made caementis harder and more durable. The Romans liked concrete because it allowed them to build thicker, sturdier walls for less money than a pure masonry wall of the same dimensions. Concrete in Roman Records A century after Cato's time, hudraulic caementis had come into more general use. The earliest reference to Roman concrete in the ancient literature is by the renowned Roman architect Marcus Vitruvius Pollio in his De Architectura; or the Ten Books on Architecture. Concrete in Roman Records By the time Vitruvius wrote his book, toward the end of the first century BC, true Roman concrete had only recently emerged from being an intriguing waterproof mortar to becoming a building material that, by itself could be used in new and creative ways. Instead of the simple wooden planks used for wall molds, more elaborate forms, called "shuttering" by today's engineers were fashioned. After Vitruvius wrote On Architecture, the next time concrete appears in the surviving literature is approximately ninety years later in Pliny the Elders' Natural History. Roman Walls Roman Aqueducts The Romans built aqueducts to bring water from distant sources into cities and towns, which supplied public baths, private households, fountains etc. They event supplied the water for their sewage systems. Aqueducts also provided water for mining operations, milling, farms and gardens. Aqua Appia, Rome's first aqueduct (312 BC) was commissioned by the censor Appius Claudius Caecus as one of two publicly funded, major projects; the other was a strategic road between Rome and Capua, the first leg of the so-called Appian Way. Roman Roads Roman roads were vital to the maintenance and development of the Roman state, and were built from about 500 BC through the expansion and consolidation of the Roman Republic and the Roman Empire. They provided efficient means for the overland movement of armies, officials, and civilians, and the inland carriage of official communications and trade goods. Via Appia was constructed 315 BC and was very vital to the Romans. Helpful Resources http://www.concreteconstruction.net/images/Roads%20o f%20the%20Roman%20Empire_tcm45-342976.pdf http://www.history.com/news/history-lists/8-ways- roads-helped-rome-rule-the-ancient-world Pantheon Rome, Italy c. 126 AD Interior Photo by Fczarnowski; Exterior Photo provided by Wikipedia. Pantheon Dome Rome, Italy c. 126 BC Use of Wooden Casting Molds Fall of Rome Infrastructure was not maintained. High taxes led to no more building. Loss of knowledge and formulas of concrete. In 1824, Joseph Aspdin, a British stone mason, obtained a patent for a cement he produced in his kitchen.