Soil composition and condition are critical factors in any construction project, which is why the International Building Code (IBC) specifies numerous regulations for special inspections. Conducted to ensure that excavation, foundation and soil properties are adequate to support a planned structure, a soils special inspection is carried out by an approved special inspector who determines compliance with applicable code and established building plans.

What the IBC Says About Soils

The International Building Code defines and outlines matters related to soils in both Chapter 17 and Chapter 18. Chapter 17 discusses the goals of soils special inspections while Chapter 18 expands on the details of investigatory methods and key criteria for successful investigations.

Required Special Inspections and Tests for Soil

According to section 1705.6 of the IBC, the approved geotechnical report and construction documents established by registered design professionals are used to determine compliance. The section also outlines the key aspects of a soils special inspection, which includes verifying the soil’s design bearing capacity, adequacy of excavations and preparation prior to filling. It also requires continuous monitoring of material quality added to the site as well as performance of tests and analysis of these substances.

Guidelines for Geotechnical Investigations

Section 1803 of the IBC defines the scope, nature and goals of geotechnical investigations on building sites. The registered design professional overseeing inspections is required to have a qualified representative on site for all boring operations and sample extractions.

The IBC specifies that geotechnical reports include essential details regarding the inspections, including a complete plot of sampling and boring locations as well as a record of soil profiles, water tables and fill material properties. Reports should also include recommendations regarding bearing capacity and potential for mitigating changes in soil conditions. Results of the various soil investigations are then submitted as part of the building permit application process.

Exceptions for Flood Hazard Areas

Soils are also mentioned in section 1804.5 of the IBC in regard to grading and fill in areas designated as flood hazards. While these activities are normally prohibited in flood zones, the code states several conditional exemptions to this rule. Typically, grading and fill must be designed to resist erosion and minimize impact on other properties.

Finding Opportunities to Improve and Innovate

Site and materials testing are absolutely essential for protecting the safety of the structure’s future occupants as well as the resources invested into the building itself. While soil investigations are obligatory, they can also open up possibilities for innovation and improvement. As a cutting-edge environmental consulting and engineering service provider, ATC Group Services helps clients achieve full compliance and seize new opportunities as they arise along the way.

Taking a Creative Approach to Testing

Innovation takes many forms, including finding new ways to measure material composition without prolonged testing. After being tasked with the placement of 18,000,000 cubic yards of soil and rocks, ATC developed a way to test rock density by measuring the rate of compaction from equipment passing over the surface. This strategy ultimately saved the client a considerable amount of time compared to conventional methods.

Considering the Alternatives

Viable designs aren’t necessarily optimized ones. After a detailed reevaluation of a 35-story high-rise residential building project, ATC professionals determined that the shaft lengths could be shortened without compromising safety or jeopardizing the structure. This insight conserved a considerable amount of money and cut roughly a month from the schedule.

Mastering Geotechnical Technology

Faced with the task of supporting one of the world’s largest aquariums on terrain dominated by soft soil, ATC applied technical and technological expertise to find an acceptable solution. Our custom pile load testing program run with electronic strain gauges allowed for a detailed analysis of the soil at a greatly reduced cost.

ATC Group Services believes that there is no substitute for an accurate, detailed and thorough soil investigation. We also know that there is little room for error when millions of dollars and years of planning are at stake. That’s why we dedicate ourselves to providing innovative and comprehensive services on every single project. Contact your local branch to learn more.