In-House Labratory Services
The Madrid Engineering Group, Inc. (MEG) Soils and Materials Laboratories are housed in two spaces, approximately 400 sq ft each. The Soils Laboratory houses equipment and space to receive and temporarily store field samples, perform visual classification of those soil samples, to perform tests resulting in data useful to classify those samples, and to prepare boring logs based on those visual classifications and boring data from the field. Tests performed in the Soil Laboratory include plastic and liquid limit determination, determination of percent passing the No. 200 sieve, stacked sieve gradation, particle size determination by hydrometer, determination of organic content, and carbonate content determination. The Materials Laboratory houses the equipment and space to perform construction materials testing including standard and modified Proctors, Limerock Bearing Ratio (LBR) determination, concrete compressive strength, and one-dimensional consolidation properties of soils. Additionally, MEG has a 3000 sq ft warehouse for long-term sample storage on three and four level steel racks, and facilities for curing concrete compressive strength test samples.
The day-to-day operations of the Soils Laboratory revolve around classification of samples and soil testing. Field samples from test borings are delivered to the lab, and logged to track custody. A technician sits down with the soil samples and boring logs to perform visual USCS determinations and MUNSEL color determinations. Soil samples are selected for testing to aid and confirm visual classifications. For both the Soils Laboratory and the Materials Laboratory, internal samples and customer samples are put into a queue for testing, from which technicians draw to perform the requested testing. Samples are processed on a loose cycle consisting of starting new samples in the morning by preparing them for drying or soaking as needed, and the previous day's samples are processed in the afternoon. Final steps are typically performed first thing the next morning. In the Soils Laboratory, with field boring logs, visual classification notes, soil colors, and test data in hand, the technician prepares the first draft of the presentation boring logs. Customer and internal sample data are reviewed by the laboratory manager before delivery. Internal sample boring logs are reviewed by project manager.
A typical day in the Materials laboratory consists of performing concrete compressive strength tests as dictated by the required break schedule for the samples. After concrete is done, the laboratory technicians will begin the processing of soil samples that were brought in the previous day for Proctor or LBR testing as needed, as well as gradation and moisture content determinations. Processing soil samples for LBR or Proctor testing generally requires the sample to be split down and sieved over ¾-inch and #4 sieves. The samples are then recombined into an appropriate number of subsamples with the same gradation as the bulk sample originally received in the laboratory. Lastly, the subsamples are moisture conditioned prior to being compacted. In the case of LBR testing, the compacted subsamples are then soaked in a tank for a period of 48 hours prior to being penetrated in the LBR load frame apparatus. Laboratory test results from the Materials laboratory are reviewed by the lab manager, who then generates a report of the testing results. The materials testing reports are reviewed by the CEI manager prior to transmission of the test data to the client.
Madrid Engineering Group, Inc. has pursued and obtained accreditation for various soil testing methods based on the guidelines of AASHTO R18, Standard Recommended Practice for Establishing and Implementing a Quality Management System for Construction Materials Testing Laboratories. The accrediting body is the Construction Materials Engineering Council, Inc. (CMEC), a not-for-profit organization based in Central Florida whose stated goals are to provide accreditation, education, and certification to the construction and engineering industry in Florida and elsewhere.