2.Models

geokon vibrating wire strain gauges come in a variety of models, all easily identifiable by the color of heat shrink which covers the protective tubes, as shown in the table below.*

*Applicable only to products manufactured after September 2016.

table 1: Heat Shrink Color Designations

The following sections describe in brief the various embedment strain gauges available from geokon.

2.1Models 4200 and 4200L

geokon Models 4200 and 4200L are designed primarily for long-term strain measurements inside mass concrete, in structures such as foundations, piles, bridges, dams, containment vessels, tunnel liners, etc.

The 4200L is a low-modulus version designed to enable early curing strains to be measured. The length of the 4200 gauge is 152 mm (6”).

 

Figure 2: Model 4200 Vibrating Wire Strain Gauge

 

Figure 3: Model 4200L Vibrating Wire Strain Gauge

2.2Models 4200-6 and 4200-7

Model 4200-6 and 4200-7 strain gauges are supplied fully sealed and pre-tensioned with the plucking coil mounted. Note the small collar under the shrink tube at one end.

 

Figure 4: Model 4200-6 Vibrating Wire Strain Gauge

 

Figure 5: Model 4200-7 Vibrating Wire Strain Gauge

2.3Model 4202

Model 4202 is designed for direct embedment in grout, mortar, and small aggregate concrete. It is also useful for model studies. The length of the 4202 gauge is 50 mm (2”).

 

Figure 6: Model 4202 Vibrating Wire Strain Gauge

2.4Model 4210

Model 4210 is designed for embedment in large aggregate concrete (greater than 3/4 of an inch). The standard gauge length is 254 mm (10”), other gauge lengths available include: Model 4212: 305 mm (12”), and Model 4214: 356 mm (14”).

 

Figure 7: Model 4210 Vibrating Wire Strain Gauge