BENEFITS> Economic Value

5541185-1.jpgThe State of California has one of the largest infrastructure networks per capita in the world. Over the past few decades, pressures on this network have increased, resulting in accelerated road damage and increased demand to upgrade portions of the network. To address sustainability issues, stakeholders are increasingly searching for environmentally sustainable and cost-effective methods of constructing new projects and reconstructing existing ones.

As local and state agencies evaluate the technical and economic feasibility of undertaking alternative construction techniques, the cost of raw materials continues to escalate at an accelerated rate. In California, the shortages and cost escalations of aggregate is felt first by regional coastal aggregate producers. The dynamics of rising land values and difficulties in obtaining site approvals are displacing aggregate producers along coastal counties.

The ability to address long-term environmental sustainability, while lowering the lifecycle cost of constructing and maintaining infrastructure projects is achievable. The chemical soil stabilization process allows for an economically attractive and technically sound solution to performance predictability in design and construction.

In 2002, California produced 223 million tonnes of aggregate, including 159 million tonnes of sand and gravel and 64 million tonnes of crushed stone. In 2002, California imported 2.2 million additional tonnes from sources in British Columbia, Canada, and Baja California and shipped to ports in San Francisco, Los Angeles, and San Diego. It is predicted that California's population of 35 million is growing at 500,000 per year and that California will require an additional 37 million tonnes per year by the year 2030, which is equivalent to 10 times Canada's largest gravel operation at Sechelt (3.1 million tonnes).

Although there is no single answer to California's ever-growing aggregate cost, there is a solution to continual shortages and escalating cost for road base and structural fill materials. As many design engineers have discovered, the chemical stabilization process, through sound engineering and distinct quality control, has begun to solve these issues by reducing aggregate demand with equivalent structural sections.

By developing an understanding of this process, engineers involved with infrastructure projects can deliver solutions to California's ever-growing needs.

 

The Cost of Transporting Aggregate (National Averages):

Layer Thickness of Typical 1.6 Kilometer length of 4-lane Highway

130 cm Crushed Aggregate

Amount of Material per Kilometer of Construction (tonnes)

14,400 Tonnes

Average F.O.B. price per ($/tonnes)

$7.72

Total Material Cost ($)

$111,000

Transportation Cost ($0.13/ton/km)

$105,000

Total Cost ($/ton)

$216,000

Percent of Total related to Transportation

49%