Technology Digests / Longitudinal Rail Force Changes from Track Maintenance: 2026 Update

TD26-018

Date Posted: August 12, 2026
Authors
  • Stephen Wilk
  • Duane Otter
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Key Findings

  • MxV Rail performed two additional revenue service tests on two different railroads. The results further confirmed that RNT change does occur near fixed objects after maintenance runoffs and showed that train direction and track type have an influence on the RNT change.
  • These four tests (two previous, two recent) suggest that wood tie track is most susceptible to RNT reduction at locations where production maintenance and loaded uni-directional traffic go into a stiff fixed object.
  • Multiple other factors, including maintenance type, tamping type and procedures, type of “fixed” object, track grade and curvature, and track condition, likely influence the RNT change.
  • The RNT change from a single maintenance event may not be large (~-5 to 10°F) compared to other factors that cause a greater RNT change (>20°F), but the accumulation of change from multiple events may produce a growing pocket of altered RNT near the fixed object.

Longitudinal Rail Force Changes from Track Maintenance: 2026 Update

In 2025, MxV Rail performed two revenue service tests to measure rail neutral temperature (RNT) changes during and immediately following production surfacing. These two tests expanded on two previous tests1,2 and focused on different track types, tamper types, and train operation directions. The long-term goal of these revenue service tests is to understand the causes and magnitudes of RNT change near fixed objects due to a range of factors, including track maintenance. This Technology Digest summarizes the results of the two 2025 tests and provides general guidance from all four tests. BACKGROUND Track buckle prevention is a difficult problem for railroads due to the lack of a scalable, direct RNT, or track buckle strength (TBS) measurement. The lack of direct measurements has led to research efforts to identify situations more prone to buckles. Two common buckle-prone situations are 1) post-maintenance track and 2) track near fixed objects. Maintenance can affect…