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Title: SUBSURFACE TEMPERATURES AND MOISTURE CONTENTS IN SIX NEW JERSEY SOILS, 1954-1955
Accession Number: 00237489
Record Type: Component
Abstract: IN THE SIX SOILS CONSIDERED, TEMPERATURES AND MOISTURE CONTENTS WERE MEASURED DAILY AT SELECTED INTERVALS OF DEPTH BENEATH THE CENTERS OF THE CONCRETE SLABS AND BENEATH THE SOIL SHOULDERS AT THE EDGE OF THE SLABS. AIR TEMPERATURE, GROUNDWATER TEMPERATURE, GROUNDWATER ELEVATION, AND THE RELATIVE VERTICAL DISPLACEMENT OF THE CONCRETE SLABS RESULTING FROM FROST HEAVE WERE ALSO MEASURED. AN ANALYSIS IS PRESENTED OF THE DATA OBTAINED. THE FIBERGLASS SOIL MOISTURE UNITS USED INDICATED SOIL MOISTURE CONTENTS TO AN APPARENT ACCURACY OF SEVERAL PERCENT. IT IS CONCLUDED THAT THERMISTORS ARE RELIABLE AND CONVENIENT FOR MEASURING SUBSOIL TEMPERATURES AS THEY CAN BE EASILY CALIBRATED TO AN ACCURACY OF 0.1 F. ELEVATION OF THE GROUNDWATER TABLE SHOWS A DIRECT RELATIONSHIP TO PRECIPITATION. PERCOLATION FROM MELTING SNOW MAY BE GREATER THAN FROM AN EQUIVALENT AMOUNT OF RAIN. THE GROUND-WATER TEMPERATURE IS CONTROLLED PRIMARILY BY THE EFFECT OF AIR TEMPERATURE. THE GREATEST DEPTH AND RATE OF FROST PENETRATION OCCURS IN THE GRANULAR SOILS AS A RESULT OF THEIR RELATIVELY HIGH THERMAL CONDUCTIVITY AS COMPARED WITH THAT OF FINE-GRAINED SOILS. BECAUSE THE THERMAL CONDUCTIVITY OF A CONCRETE SLAB IS GREATER THAN THAT OF AN EQUAL DEPTH OF SOIL, FROST USUALLY PENETRATES DEEPER BENEATH THE SLABS AND THROUGH THE SHOULDERS. FOR THE SAME REASON, THE SOILS THAW FASTER BENEATH THE SLABS. THE GREATER RATE OF THAWING BENEATH PAVEMENT SLABS MAY PRODUCE POCKETS OF THAWED SOIL AT HIGH MOISTURE CONTENT FROM WHICH THE WATER CANNOT DRAIN. CONSEQUENTLY, THE SOIL BEARING CAPACITY IS REDUCED BECAUSE OF THE SATURATED STATE OF THE SOIL. THE GREATEST DEPTH OF FROST PENETRATION DOES NOT NECESSARILY OCCUR AT THE SAME TIME AS MINIMUM AIR TEMPERATURE. THE SILTY SOILS ARE MOST SUSCEPTIBLE TO FROST HEAVING WHILE THE GRANULAR SOILS HEAVE THE LEAST. MAXIMUM FROST HEAVING DOES NOT NECESSARILY OCCUR SIMULTANEOUSLY WITH THE MAXIMUM DEPTH OF FROST PENETRATION. FROST HEAVING IS DEPENDENT UPON SOIL MOISTURE CONTENT RESULTING FROM PRECIPITATION OR PROXIMITY TO GROUND-WATER AS WELL AS UPON THE AMOUNT OF FROST PENETRATION RESULTING FROM FREEZING TEMPERATURES. SOIL FREEZES AT TEMPERATURES SLIGHTLY LOWER THAN 32 DEGREES F. FINE-GRAINED SOILS NORMALLY RETAIN HIGHER MOISTURE CONTENTS THAN COARSE-GRAINED SOILS. MOISTURE CONTENTS USUALLY INCREASE WITH DEPTH IN A SOIL.
Supplemental Notes: No 135, pp 77-108, 18 FIG, 7 TAB, 3 REF, 1 APP
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Monograph Title: Monograph Accession #: 01410536
Authors: Turner, K AJumikis, Alfreds RPublication Date: 1956
Serial: TRT Terms: Uncontrolled Terms: Old TRIS Terms: Subject Areas: Geotechnology; Highways; Hydraulics and Hydrology
Files: TRIS, TRB
Created Date: Jul 22 1994 12:00AM
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