Chapter 3 Structural Infrastructure Copyright © 2012 by John Wiley & Sons, Inc. All rights reserved. Introduction to Infrastructure: An Introduction to Civil and Environmental Engineering First Edition Michael R. Penn and Philip J. Parker

 Infrastructure Sectors: Transportation, Environmental, and Structural  Subsectors: Mass transit, aviation, etc.  Components: Roadways, rail lines, etc.  Subcomponents: Curbs, pavement, etc.

 ASCE Report Card started 1988 by congressional chartered commission. 1988: C 1998: D 2001: D+ 2005: D 2009: D

 Schools are typically one of the largest expenses for a community.  Each community must decide how large of a school to build. Too big: huge debt. Too small: substandard temporary classrooms.  Difficult in many areas with rapidly growing or shrinking populations.

 There have been no extensive studies since  Significant budget cuts in the last several years.  Huge disparity in education quality linked to district affluence.

 Choice of bridge type depends on: Distance to be crossed Site geology Construction conditions Traffic type Funding  US bridge stats: ASCE 2009 Grade: C 600,905 bridges Average age: 43 years old Typical design age: 50 years 12.1% are structurally deficient 14.8% are functionally obsolete

 Used for navigation, flood control, hydroelectric power, water supply, flood control, and recreation.  Almost exclusively earthen or concrete.

 Major dams – over 50ft tall with >5,000 ac-ft of storage or anything with >25,000 of ac-ft storage.  Spillways – engineered channels to keep dams from overtopping by bypass the dam.  Fish ladders/elevators – mechanisms that allow fish migration over the dam.

 Over 80,000 damn in the US  1,700 high-hazard dams in need of repair (2007)

 Levees/Dikes – earthen embankments  Floodwalls – typically concrete Floodgates – Installed in floodwalls to be closed during flood conditions.

ASCE 2009 Grade: D-

 Only 10 states keep listings of levees.  Only 23 states have agencies in charge of levee safety.  Levees in 22% of all counties in the US.  Levees that once just protected agriculture now protect residential neighborhoods.

 Retaining wall – used to eliminate slopes to create a greater developable area.

 Must be able to resist lateral earth pressure and hydrostatic pressure (unless properly drained.)

According to ASCE we need an additional investment of $641 billion !