Fully Automatic Residual Direct Shear Apparatus BTU-DDS-10 / DDS-5 / DDS-5F / DDS-10F
Description
This series consists offully automatic residual direct shear apparatusesusing a microprocessor‑controlled drive system and keypad command
input. Advantages include the ability to pause and reset the test
speed, computer control via USB 3.0 interface, programmable speed
and functions by the operator, and a self‑check system. The fast
return to initial position function provides a convenient way to
reset the shear box when starting a new test or continuing a
residual shear test.
Models include:
- BTU-DDS-10: British Standard direct shear apparatus (lever loading)
- BTU-DDS-5: American Standard direct shear apparatus (lever loading)
- BTU-DDS-5F: Fully automatic residual direct shear apparatus (5 kN)
- BTU-DDS-10F: Fully automatic residual direct shear apparatus (5 kN? the table
shows 5 kN, but the model suggests 10 kN – verify with
manufacturer)
Main functions:
- Standard consolidation, standard shear, fast shear, cyclic shear,
rheological direct shear
- Optional interface friction test module and temperature control
module
Test Standards (International)
- British Standard (BTU-DDS-10): Complies withBS 1377
- American Standard (BTU-DDS-5): Complies withASTM D3080
- Fully automatic residual models (DDS-5F / 10F): Can meet both British and American standards as well as residual
strength test standards such asASTM D7608,ASTM D6467(confirm with manufacturer).
Other relevant standards:
- ISO 17892-10(Direct shear test)
- AASHTO T-236
- EN 1997-2(Eurocode 7)
Specification
| Parameter | BTU-DDS-10 (British) | BTU-DDS-5 (American) | BTU-DDS-5F | BTU-DDS-10F |
| Instrument name | British Standard direct shear | American Standard direct shear | Fully automatic residual direct shear | Fully automatic residual direct shear |
| Specimen size (mm) | 60×60 / 100×100; 2.416 in or 2.5 in | 60×60 / 100×100; 2.416 in or 2.5 in | 61.8*20 | 100×100 & 60×60 |
| Shear rate (mm/min) | 0.00001–9.99999, stepless | 0.00001–9.99999, stepless | 0.00001–9.99999, stepless | 0.00001–9.99999, stepless |
| Loading method | Lever loading | Lever loading | Fully automatic servo closed‑loop loading | Fully automatic servo closed‑loop loading |
| Control method | 16‑key membrane keypad + 240×128 LCD |
| Max. shear displacement | 25 mm | 25 mm | 25 mm | 25 mm |
| Normal force (kN) | 5 | 5 | 5 | 5 |
| Horizontal shear force (kN) | 5 (optional 10 kN) | 5 (optional 10 kN) | 5 (optional 10 kN) | 5 (optional 10 kN) |
| Data acquisition | Data logger + Windows software | Data logger + Windows software | Fully automatic servo closed‑loop control | Fully automatic servo closed‑loop control |
| Included modules | Standard consolidation, standard shear, fast shear, cyclic shear,
rheological direct shear |
| Options | Interface friction test module, temperature control module |
Note: Although the BTU-DDS-10F model name includes “10F”, the table
still lists normal force and horizontal shear force as 5 kN – this
may be a typo; check with the manufacturer for actual
specifications.
Detail
- Microprocessor control system– Programmable test speed, pause, reset; USB 3.0 communication with
computer.
- Fast return to initial position– Automatically returns the shear box to its starting position
after a test or during residual shearing, improving convenience.
- Dual standard compatibility– British Standard (DDS-10) uses square specimens (60×60 or
100×100 mm); American Standard (DDS-5) uses round specimens
(Φ61.8×20 mm).
- Fully automatic residual models (DDS-5F/10F)– Servo closed‑loop loading, automatic reciprocating shearing for
residual strength testing.
- Lever loading (DDS-10/5)– Traditional weight loading, simple and reliable, but requires
manual weight changes.
- Wide shear rate range– 0.00001–9.99999 mm/min, covering slow to fast shear.
- Large shear displacement– Up to 25 mm, much larger than conventional direct shear (6‑8 mm),
suitable for residual strength testing requiring large
displacement.
- Optional modules– Interface friction (soil‑structure, geosynthetics) and
temperature control (range to be confirmed).
- Software modules– Standard consolidation, standard shear, fast shear, cyclic shear,
rheological direct shear, etc.
Application
- Residual strength testing– Determine residual shear strength (cᵣ, φᵣ) of slip zone soils,
fault gouge, etc., under large displacement.
- Conventional direct shear tests– Fast shear, consolidated shear, slow shear to obtain peak
strength.
- Cyclic shear– Simulate strength degradation under earthquake or wave loading.
- Rheological direct shear– Study long‑term creep behaviour of soils.
- Interface friction– With optional module, test soil‑concrete, soil‑geomembrane, etc.,
interface friction angles.
- Temperature‑controlled tests– With optional temperature module, study temperature effects on
shear strength.
- Compliance with international standards– Meets BS 1377 and ASTM D3080, suitable for domestic and
international projects.
Advantages
- Multiple standard compliance– Dedicated British and American Standard models, plus general
fully automatic residual models.
- Large shear displacement (25 mm)– Better suited for residual strength testing than conventional
direct shear (6‑8 mm).
- Fully automatic servo closed‑loop (F models)– Automatic reciprocating shearing without manual intervention,
precise stress/strain path control.
- Wide shear rate range– 0.00001–9.99999 mm/min stepless, from creep to fast shear.
- USB 3.0 interface– High‑speed data transfer, remote control capability.
- Fast return function– Improves efficiency, especially for multi‑stage residual
shearing.
- Modular software– Consolidation, shear, cyclic, rheological modules can be combined
as needed.
- Expandability– Optional interface friction and temperature control modules.
What To Choose
Select the model based on testing requirements:
| Requirement | Recommended Model | Reason |
| Need compliance with BS 1377, square specimen (60×60 or 100×100 mm) | BTU-DDS-10 | British Standard dedicated, lever loading, lower cost |
| Need compliance with ASTM D3080, round specimen (Φ61.8×20 mm) | BTU-DDS-5 | American Standard dedicated, lever loading |
| Need residual strength (reciprocating shear) with full automation | BTU-DDS-5F or 10F | Servo closed‑loop, automatic reciprocating shear, large
displacement (25 mm) |
| Need higher horizontal shear force (>5 kN) | Optional 10 kN upgrade (all models support) | Suitable for high‑strength or coarse soils |
| Need interface friction testing | Any model + optional interface friction module | Requires special fixtures |
| Need temperature control (e.g., frozen or high temperature) | Any model + optional temperature module | Temperature range to be confirmed |
| Only routine direct shear, no residual or cyclic requirements | DDS-10 or DDS-5 (based on specimen shape) | Lower cost |
| Limited budget but want future upgrade | Buying a lever‑loading model then upgrading to servo is not
feasible – buy F model directly | Servo and lever hardware are different |
Note: The main difference between DDS-5F and DDS-10F may be
specimen size (DDS-5F for round American specimens, DDS-10F for
square British specimens), but the table is unclear – confirm with
the manufacturer.
Process Flow
Example:Residual strength test on saturated clay (reciprocating shear)
using the fully automatic residual direct shear apparatus (BTU-DDS-5F)
- Specimen preparation
- Cut undisturbed or remoulded clay specimen using a Φ61.8×20 mm
cutting ring; saturate.
- Measure initial water content and density.
- Specimen installation
- Place the specimen into the lower shear box, install upper box,
porous stones, and loading plate.
- Position the shear box in the direct shear loading frame, connect
normal and horizontal loading rods.
- Install displacement sensors (horizontal and vertical).
- Apply normal stress
- Apply the target normal stress (e.g., 100 kPa) via the servo
closed‑loop system.
- Record normal displacement until consolidation is stable (drained
condition).
- Set shear parameters
- Select “residual shear module” or “reciprocating shear module”.
- Set shear rate (e.g., 0.5 mm/min).
- Set forward shear displacement limit (e.g., 10 mm).
- Set reverse shear displacement limit (e.g., 10 mm) and number of
cycles (e.g., 5).
- Choose control mode: strain control (typical).
- Start reciprocating shearing
- The horizontal servo system pushes the shear box forward; after
reaching the forward limit, it automatically reverses.
- Software records shear force, displacement, and time for each
half‑cycle in real time.
- Plot shear stress‑displacement curve (multiple cycles).
- Stop condition
- Automatically stops when the preset number of cycles is completed
or shear stress stabilises (residual strength achieved).
- Disassembly and cleaning
- Unload normal force, remove specimen, clean shear box.
- Data processing
- Software automatically identifies peak shear stress (first cycle)
and stabilised shear stress (residual) for each half‑cycle.
- For tests at different normal stresses, plot residual strength
envelope to calculate cᵣ and φᵣ.
- Generate test report.
For lever‑loading models (DDS-10/5): Normal stress is applied manually using weights; during shearing,
manual recording or an external data logger is required.
Summary:This series offers British Standard (square specimen), American
Standard (round specimen) lever‑loading direct shear apparatuses,
as well as fully automatic servo closed‑loop residual direct shear
apparatuses (5F/10F). The fully automatic models support
large‑displacement reciprocating shear for residual strength
testing. All models can be optionally equipped with interface
friction and temperature control modules, and feature rich software
test modules. Selection should be based on specimen shape,
compliance with specific standards, need for fully automatic
residual shear testing, and whether higher shear force (10 kN) is
required.