Author: William Edward WolfePublisher:
ISBN:
Category : Pavements
Languages : en
Pages : 46
Book Description
Environmental instruments to measure temperature, soil moisture and frost depth were installed at five test sections of the SHRP pavement project on U.S. 23 north of Delaware, Ohio. At three of these locations tensiometers, which a designed to measure negative pore pressures, were added to the instrumentation package. The pore pressures as recorded by the tensiometers have increased from initially negative to positive values at each location and throughout the profile in the first year after installation of the instrument package was completed. At the same time, data collected from the moisture probes were showing a corresponding increase in soil moisture content. Samples of an aggregate base and clayey subgrade material were collected at several locations on the DEL 23 project by ODOT. They were delivered to the OSU soil mechanics laboratory for classification and permeability determination. The aggregate base conformed to ODOT material specification Item 304. Measured permeability coefficients ranged between 2x10 [to the minus 2] and 2.9x10 [to the minus 2] cm /sec. The clayey material was classified as a low plasticity clay (AASHTO Classification A-6 to A-7-6) with permeability coefficients ranging between 1x10 [to the minus 6] and 4x10 [to the minus 8] cm/sec.