College of Engineering and Applied Science

The laboratory occupies 5,100 square feet with the main structural testing area consisting of a 30 feet wide by 50 feet long strong floor. This area consists of tie downs that allow for the construction of test frames and the testing of full-scale structural members. A 20-kip overhead traveling crane services this area. The laboratory is equipped with a concrete moisture curing room, concrete durability room, adequate space for the fabrication and testing of specimens and sufficient space for material and specimen storage.

Three computer controlled uniaxial test frames (20kip, 220kip and 1000kip) are used to evaluate structural materials, connections and components. In addition, the laboratory is equipped with numerous hydraulic rams, pumps, data acquisition systems and other necessary materials to evaluate structural systems.

The structures lab is located in North Classroom room 1805. The lab is run by the following professors:

Kevin Rens, kevin.rens@ucdenver.edu
Fred Rutz, frederick.rutz@ucdenver.edu
Cheng Yu Li, cheng.li@ucdenver.edu
Peter Marxhausen, peter.marxhausen@ucdenver.edu

Kevin L. Rens

My research interests are these three areas:

• Inspection, rating, maintenance and repair
• Nondestructive evaluation and failure analysis of infrastructure
• Cement and concrete properties

The structural laboratory facility includes standard laboratory equipment for the production and testing of concrete. The concrete materials laboratory includes:

• A concrete mixer with a mixing capacity of 5 cf
• Adequate space for batching and testing of concrete mixtures
• Water-lime tanks used for moist curing (temperature controlled and monitored with circulating pumps)
• A temperature controlled room curing room

Fresh concrete properties testing equipment available to test:

• ASTM C143 Test Method for Slump of Hydraulic-Cement Concrete
• ASTM C1064 Test Method for Temperature of Freshly Mixed Portland Cement Concrete
• ASTM C138 Test Method for Unit Weight, Yield, and Air Content (Gravimetric) of Concrete ASTM C231 Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method
• ASTM C173 Test Method of Air Content of Freshly Mixed Concrete by the Volumetric Method

Hardened concrete properties testing equipment available to test:

• ASTM C 39 Test Method for Compressive Strength of Cylindrical Concrete Specimens
• Forney, Inc. 400 kip concrete compression machine with a digital display that provides load, peak load, loading rate and compressive strength
• Capability of testing 6” x 12” cylinders with a compressive strength up to 14,000 psi or 4” x 8” cylinders with a compressive strength up to 31,000 psi can be tested in this machine
• UC Denver has the capability of using sulfur caps or unbonded caps when testing cylinders for compressive strength
• ASTM C666 Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing
• ASTM C1202 Standard Test Method for Electrical Indication of Concrete Ability to Resist Chloride Ion Penetration
• ASTM C 157 Standard Test method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete
• ASTM C1012 Standard Test Method for Length Change of Hydraulic-Cement Mortars Exposed to a Sulfate Solution

Nondestructive testing of structures concrete ultrasound

• Steel ultrasound
• Magnetic particle
• Dye penetrant
• Concrete strain gauge
• Steel strain gauge
• Rebound hammer
• Impact echo

Laboratory Classes

CVEN 3141 – Introduction to Structural Materials

Course Objective: To acquire the basic understanding of the production, properties and behavior of common structural materials. In addition, it is the goal of a student to develop solutions to problems by working individually and with others and present these solutions in a clear and professional manner.

This course will focus on materials used in the construction of structures. Emphasis will be placed on concrete, steel and wood. In addition, advanced materials may be covered, time permitted. At the end of this course, the student will have a clear understanding of the production, properties and behavior of concrete, steel and wood. In addition, students will be able to demonstrate effective communication skills through the writing of laboratory reports and in-class presentations.

Laboratory Topics:

Lab #1: Gradation, Moisture Content, Unit Weight of Coarse and Fine Aggregates

Lab #2: Specific Gravity and Absorption Capacity of Coarse and Fine Aggregates

Lab #3: Compressive Strength vs. Water-to-Cement Ratio

Lab #4: Fresh Concrete Properties Testing - Slump, Air Content, Unit Weight and Temperature

Lab #5: Mixture Proportioning and Trial Batching

Lab #6: Mixture Re-Proportioning and Rebatching

Lab #7: Special Topic

Lab #8: Testing of Metals – Heat Treatments

Lab #9: Testing of Wood – Behavior of Wood Parallel and Perpendicular to the Grain

Class Design Project: The High-Strength Green-Crete (HSGC) Contest (it will involve developing a concrete mixture and batching and testing the mixture). The HSGC Contest involves designing and mixing a concrete mixture that includes recycled materials (slag, fly ash and silica fume) and comparing it to a standard concrete mixture. In addition, each group will be competing against one another for the concrete mixture with the highest 28-day compressive strength. Included in the project will be a professional report and presentation to the class.

American Concrete Institute Grade I Field Certification Program: This program is conducted in cooperation with the Colorado Ready-Mixed Concrete Association, Colorado Department of Transportation, and ACI. In addition, this is the only ACI Grade I Field Certification program for students in the State of Colorado. There is a fee (established by ACI and CRMCA) associated with this program. This fee covers the costs associated with printing, administration, as well as shipping and handling of exam materials.

The purpose of this program is to certify individuals to conduct physical tests, in the field, on fresh concrete. These tests are conducted, in part, to insure compliance with job specifications. Being certified is significant in that many construction contracts require compliance testing to be conducted by certified technicians. In addition, certification is now required for anyone who works on a Colorado Department of Transportation job.

An added benefit of this certification is that students are more "marketable" for summer and long-term employment. On average, one to three students from each class obtain summer jobs, or advance in their job, as a direct result of being certified.