Mississippi MDOT Geotextile Fabrics

Solmax DOT Standard Specification Product Chart (click image to expand)

Mississippi MDOT - Geotextile Uses

Mississippi projects span Delta clays (including expansive Yazoo clays), loess hills, coastal sands, and broad floodplains with high groundwater. Add tropical systems, intense convective storms, river flooding, and heavy freight traffic, and you get subgrades that can soften, pump fines, rut, scour, and lose material. Geotextiles are the quiet engineering layer that helps pavements, structures, and drainage systems keep performing under those stresses.

Separation and stabilization. On new lanes, shoulder widenings, and rehab work, a woven geotextile is placed between native soil and granular base. It prevents fine soils—especially plastic clays and loess—from migrating up into the aggregate under traffic, spreads load, and preserves base thickness. Where subgrades are very soft or saturated (Delta bottoms, coastal lowlands, utility crossings), crews roll out fabric to create a working platform so trucks and pavers don’t punch through. On exceptionally weak ground, the geotextile is often paired with a geogrid to add stiffness and speed construction.

Filtration and drainage. Water drives many failures in Mississippi. Nonwoven geotextiles line underdrain trenches, wrap perforated pipe, and separate drainage stone from surrounding soils behind retaining walls, abutments, and wingwalls. Selecting the right apparent opening size (AOS) and permittivity lets water move while fines stay put, reducing clogged outlets, wet spots, and shoulder drop-offs. In freeze–thaw pockets in the north, pairing a nonwoven with open-graded aggregate also forms a capillary break, limiting upward moisture that weakens base layers in winter.

Riprap underlayment and scour control. Where flows concentrate—culverts, storm outfalls, streambanks, river bends, and coastal works—geotextiles serve as underlayment beneath riprap or rock armor. A robust nonwoven filter goes on the prepared slope or bed before stone placement. It prevents subgrade from piping through rock voids during high velocities, hurricane-driven surge, drawdown, and debris-laden floods, helping the rock “lock in” and protecting embankments at bridge approaches and channel transitions along rivers like the Mississippi, Pearl, and Pascagoula.

Structures and MSE walls. MDOT corridors include mechanically stabilized earth (MSE) walls and grade separations. Geotextiles act as joint and face filters, tucked behind panel or block joints so backfill fines don’t migrate to the face while preserving drainage continuity. The same concept applies at wingwalls, backwalls, and structural penetrations, where a filter layer keeps weeps functioning and facias clean.

Pavement interlayers. Asphalt-impregnated nonwoven geotextile beneath overlays improves waterproofing and slows reflective cracking—important where high temperatures, heavy axle loads, and frequent wetting accelerate pavement aging. On chip seals common to rural routes, paving fabrics limit water intrusion into base and subgrade, extending service life with minimal added thickness.Temporary erosion and sediment control. Geotextiles appear in silt fence, inlet protection, curb socks, and ditch checks. They filter runoff while trapping fines—critical for stormwater compliance on long medians, steep cuts, and urban work zones. At project entrances, stabilized construction exits typically include a nonwoven geotextile under coarse rock; the fabric spreads wheel loads and prevents stone from punching into wet soils, reducing track-out onto public roads.

Liner protection and containment. Heavy nonwoven geotextiles cushion geomembranes in stormwater basins, lined ditches, salt-shed pads, and brine containment, protecting liners from puncture by angular aggregate and construction traffic.

Field practice. Performance hinges on basics: prepare subgrades smooth, avoid wrinkles, overlap or sew seams as required, anchor with pins or the first lift, and cover promptly to limit UV degradation. Selection is function-driven—woven for stabilization and tensile capacity; nonwoven for filtration, drainage, and protection—tuned to Mississippi’s soils, hydraulics, and traffic demands.

Bottom line: on MDOT projects, geotextile isn’t “landscape fabric.” It’s a purpose-chosen engineering layer that stabilizes soft ground, controls water and fines through storms and floods, protects structures and channels, and stretches pavement life statewide.

Mississippi MDOT