CIMACH YYL200 Geotechnical Compression Rheometer

Overview

The CIMACH YYL200 Geotechnical Compression Rheometer is a precision-engineered electromechanical testing system designed for controlled long-term mechanical characterization of quasi-static viscoelastic behavior in geomaterials. It operates on the principle of uniaxial compression under either force-controlled (creep) or displacement-controlled (stress relaxation) boundary conditions, enabling rigorous quantification of time-dependent deformation responses—including primary, secondary, and tertiary creep stages—as well as stress decay kinetics under fixed strain. The system integrates high-stiffness load frame architecture with closed-loop servo-hydraulic or electrodynamic actuation (depending on configuration), ensuring minimal compliance-induced artifacts during multi-day or multi-week tests. Its design conforms to fundamental requirements for geomechanical rheological testing outlined in ASTM D7012 (Standard Test Methods for Compressive Strength and Elastic Moduli of Intact Rock Core Specimens), ISO 11403-2 (Plastics—Determination of Mechanical Properties Under Dynamic Loading—Part 2: Creep Behavior), and China’s GB/T 50266–2013 (Standard for Laboratory Testing Methods of Engineering Rock Masses). It is deployed in geotechnical laboratories, civil engineering research centers, and nuclear waste repository safety assessment programs where quantitative prediction of rock mass deformation over decades is essential.

Key Features

• Full dual-mode control architecture: simultaneous force- and displacement-based regulation with seamless switching between creep and stress relaxation test protocols
• High-resolution digital transduction: ±0.5% full-scale accuracy across 1–100% of 200 kN capacity; ±0.003 mm displacement resolution over 0–15 mm range
• Programmable multi-segment loading sequences: up to 50 independent steps per test, supporting both monotonic and cyclic loading/unloading profiles
• Extended-duration stability: verified continuous operation for ≥500 hours without thermal drift or control loop degradation
• Modular platen system accommodating standard Ø61.8 mm × 20 mm cylindrical specimens per ISRM and ASTM core geometry conventions
• Integrated environmental shielding options (optional): temperature-controlled chamber compatibility for coupled thermo-mechanical rheology studies

Sample Compatibility & Compliance

The YYL200 accommodates intact rock cores (e.g., granite, shale, sandstone), compacted soil specimens (clay, silt, loam), cementitious composites (concrete, grout, shotcrete), and engineered backfill materials. Specimen preparation follows standardized coring, end-finishing, and saturation protocols per ASTM D4543 and ISO 14688-1. All force and displacement measurements are traceable to national metrological standards via factory calibration certificates compliant with ISO/IEC 17025. The system supports audit-ready documentation generation aligned with GLP and GMP frameworks, including electronic signatures, version-controlled test method templates, and raw data immutability logs required for regulatory submissions under US FDA 21 CFR Part 11.

Software & Data Management

CCPS V5.0 is a Windows-based, real-time rheological data acquisition and analysis platform developed specifically for geotechnical compression testing. It provides synchronized sampling of axial load, vertical displacement, and elapsed time at user-defined intervals (10 ms to 10 min). Built-in mathematical modules compute time-dependent parameters including creep compliance J(t), relaxation modulus E(t), Burgers model coefficients, and secondary creep rate (đε/đt)_s. Export formats include CSV, MATLAB .mat, and HDF5 for third-party finite element post-processing. Audit trails record operator ID, timestamped parameter changes, calibration events, and software version history—fully compliant with ALCOA+ (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available) data integrity principles.

Applications

• Long-term stability assessment of underground excavations and tunnel linings
• Time-dependent deformation modeling for radioactive waste disposal vaults in argillaceous host rocks
• Creep rupture analysis of shale gas reservoir caprocks under sustained overburden stress
• Constitutive model validation (e.g., Nishihara, Findley, or fractional derivative models) using multi-stage constant-load tests
• Quality assurance of engineered clay barriers in landfill liner systems
• Calibration of discrete element method (DEM) contact laws using microscale creep response data

FAQ

What specimen geometries are supported beyond the standard Ø61.8 mm × 20 mm cylinder?
Custom platens and alignment fixtures can accommodate specimens ranging from Ø30 mm to Ø100 mm diameter and heights up to 50 mm, subject to maximum stroke and load frame constraints.
Does the system support automated humidity or pore pressure control during testing?
Yes—when integrated with optional triaxial cell accessories and pore fluid delivery modules, the YYL200 enables fully coupled consolidation–creep testing under controlled effective stress conditions per ASTM D4767.
Can CCPS V5.0 import external environmental sensor data (e.g., temperature, acoustic emission)?
Yes—the software features open API hooks and configurable analog input channels for synchronized ingestion of third-party sensor streams, including AE event counts, thermocouple readings, and LVDT feedback from lateral strain gauges.
Is remote monitoring and control available for unattended long-duration tests?
The system supports secure RDP and VNC access over institutional LAN/WAN; all critical alarms (overload, thermal cutoff, communication timeout) trigger email/SMS notifications via SMTP integration.
How is calibration maintained over extended operational periods?
CCPS V5.0 includes automated zero-drift compensation routines executed prior to each test sequence; annual third-party recalibration is recommended and documented per ISO/IEC 17025-accredited laboratories.