Rowe and Bardon consolidation Cell 압밀시험

영신컨설턴트 (02) 529 8803 ystcha@naver.com 2020 9

 

 

압밀 연약지반 배수설계를 위한 수평압밀계수 Ch 측정

 

 

수직 배압용 압력장치 2개 수직변위 간극수압측정

 

radial & vertical drainage.

 

Pressure Range: 3.5MPa Accuracy of pressure measurement:

 

Sample size : 50, 61.8, 63.5, 70, 76.2 or 100mm

 

Rowe & Barden consolidation cell for 70mm diameter (Radial Drainage).

 

Each cell is supplied with three valves, a sintered bronze porous base & top disc and two flexible porous plastic top discs.

 

Back pressure can be applied to the top or base of the sample and drainage can occur to the side wall of the cell which is lined with alow friction porous media. Maximum pressure: 3500kPa

 

- 일반 압밀 Stepped loading

- 정 변형 압밀 Constant Rate of Strain (CRS) with controlled hydraulic gradient

- 정 하중압밀 Constant Rate of Loading (CRL) with controlled hydraulic gradient

- 정 간극수압 압밀 Controlled Hydraulic Gradient

- 포화 Saturation Ramp with control of axial stress or axial effective stress

- 포화도 B check- Constant axial stress or axial effective stress

 

Rowe cell vertical drain 연직배수	Rowe cell radial drain 수평배수

 

 

연직 드레인 설계

For the coefficient of horizontal consolidation ch, the Rowe cell test is frequently used as a laboratory testing method (Rowe and Barden, 1966).

 

 

 

 

분석

연직배수 vertical drainage test (Wissa et al., 1971)

- Nonlinear steady state theory accepted in ASTM
- Average effective vertical stress
- Coefficient of consolidation for vertical flow

σv : total vertical stress,
H : current specimen height,
ub : excess pore pressure at the bottom
σv1 , σv2 : total stresses at times 1t , 2t , respectively

 

 

radial drain 수평배수 outward drainage test

 

- Average effective vertical stress

uc : excess pore pressure at the center of the sample,

α ro : the ratio of average pore water pressure (u ) to the pore pressure at center.

R : the radius of the sample.

 

 

 

 

Rowe cell 다공질판

 

 

연직배수	수평배수

 

 

 

수평배수(좌)       연직배수(우)

 

 

piston sampler 시료직경 70-74 mm.

Schematic of hydraulic piston sampler operation using a thin-walled sampling tube (from ASTM D6519-08 [4])