week 10 activity - faculty of civil engineering, · pdf fileweek 11 : coverage : methods of...
TRANSCRIPT
ACTIVITY
WEEK 10
Lecture (3 hours)
Week 11 : Coverage : Methods of monitoring settlement
and horizontal movement
LEARNING OUTCOMES
Learning outcomes:
At the end of this lecture/week the students would
be able to:
Discuss horizontal movements using
inclinometers
Discuss the methods for monitoring settlement
using settlement marker
INCLINOMETER
• Application of Inclinometer
An inclinometer or clinometer is an instrument for measuring angles of slope (or tilt), elevation or inclination of an object with respect to gravity. It is also known as a tilt meter, tilt indicator, slope alert, slope gauge, gradient meter, gradiometer, level gauge, level meter, declinometer, and pitch & roll indicator. Clinometers measure both inclines (positive slopes, as seen by an observer looking upwards) and declines (negative slopes, as seen by an observer looking downward).
PIEZOMETER RESULT
• Groundwater level was monitored from three
(3) installed standpipes piezometer at BH1,
BH2 and BH3
• The higher are approximately RL 367.30m
(BH1) = 5.57m below existing ground
• The lowest are approximately RL 355.41m
(BH3) = 2.20m below existing ground
• Detail data collection for Piezometer Pipe.
MACKINTOSH PROBE
• Locations of Mackintosh Probe
• The purpose of Mackintosh Probe were carried
out to get a significant indication of the subsoil
in situ strength in residual soil weathering
grade
• This test is more cheaper compared to
borehole.
CORELATION OF MACKINTOSH
PROBE AND BEARING CAPACITY
LABORATORY TEST
• TRIAXIAL TEST
- Unsonlidated Undrained
Test (UU)
- Parameter Obtain
a. Cohesion, C kN/m2
b. Angle Friction, 0
• Provide adequate information for site
assessment, safe and economical designs of
temporary and permanent works.
PROJECT BRIEF
• NAME OF PROJECT : PEMBINAAN PANGKALAN PASUKAN
POLIS MARIN DI PELABUHAN KLANG
(FASA I) SELANGOR DARUL EHSAN
• LOCATION : PULAU INDAH, SELANGOR D.E.
• CLIENT : JABATAN KERJA RAYA(CAWANGAN
PANGKALAN UDARA & MARITIM
• CONTRACTOR : PULAU REKA-KEMBANG MAJU J.V.
• INSTRUMENTATION
MONITORING & CONTRACTOR : TECHNIQUES GEOSYSTEM
• PROJECT COST : RM 54,500,000.00
SCOPE OF WORKS
• The Objective of Works To Be Carried Out:
-Understanding subsurface condition
and geology at study area.
-Understanding settlement problem by
using Terzaghi and Superposition
Method.
• Con’t
-Understanding settlement and
consolidation without treatment.
-During construction
-Post construction
-Understanding settlement and
consolidation with treatment.
-Design Parameters and laboratory
testing.
Geology And Subsurface Conditions
• North Port area, where the soils is marine clay.
• Sometime the water level is high and saturated.
• The location is too close to the beach.
• Strength of soils:
-Very soft clay / silt SPT-N 0-2
-Soft clay / silt SPT-N 2-4
Borehole Machine and Samples
• Type of machine is wash drilling machine
-3 borehole were drilled for this project.
• Types of samples is disturb, undisturbed, and mazier samples.
• Termination of BH1 is 11.00 meters, BH 2 is 10.50 meters and BH3 is 11.00 meters.
• Subsoil of cohesive soil consist of :
-Very Soft Clay SPT-N Value (0 – 2)
-Soft Clay SPT-N Value (2 - 4)
-Firm SPT-N Value (4 – 8)
-Stiff SPT – N Value (8 – 15)
-Very Stiff SPT – N Value (15 – 30)
-Hard SPT –N Value ( >30)
Borehole Machine on Site
Con’t
Con’t
Con’t
Con’t
Con’t
RELATIONSHIP BETWEEN TRIAXIAL AND SITE
CONDITION
(Settlement and Consolidation)
Settlement
• Design Data
-Settlement
Hd Ce log(PoP1)
(1+e) Po
- From sample UD1.
- Result Odometer Test.
- Plot graph Void Ratio Vs Applied Pressure
-Obtained design parameters such as:
eo,Cc,Po,P1 and Hd.
-Finally Sf=Si+Sp+Sc (Principle of Superposition)
DEGREE OF CONSOLIDATION
• By using formula :
Tv =Cv t Refer to graph
Hd2 Tv Vs Uav Uav %
Then Settlement During Construction
Settlement Post Construction
(Settlement Without Treatment)
• Where Consolidation With Treatment
-Based on time for rest period in percentage.
-Based on principle of superposition, Sc
INSTALLATION OF SURFACE SETTLEMENT MARKERS
• To monitor vertical movement of the ground or
embankment surface
• Location of SSM – Instruction from the Engineer
• Steel rod – 20mm diameter
• Minimum driven distance – 0.5m
• Surrounded by 300mm x 300mm x 300mm
of concrete
SEQUENCE OF INSTALLING SETTLEMENT MARKER
SEQUENCE OF INSTALLING SETTLEMENT MARKER
INSTALLATION OF ROD SETTLEMENT GAUGES
• To measure settlement taking place beneath and adjacent to embankment
• Location of SSM – Instruction from the Engineer
• Base plate and first length of RSG shall put in place
during earthwork
• Extension length of RSG shall be install
when compacted embankment is 250 mm
SEQUENCE OF INSTALLING SETTLEMENT MARKER
SEQUENCE OF INSTALLING SETTLEMENT MARKER
LOCATION OF TEST INSTRUMENTS
Deep Settlement Gauge Settlement MarkerPiezometer
MONITORING OF INSTRUMENTS
• Monitored by standard leveling technique
• Levels shall be taken from the top of the rod.
• One point taken into consideration
• Following records are required
REPORTING
• A tabulated data and plot of settlement against time.
• Detail result
RECORD REQUIRED
• Reduced level of top of rod
• Original ground level at gauge location
• Reduced level of ground at adjacent to gauge
• Record of fill placed
• Total thickness of fill
• Record of extensions
• Settlement of plate relative to the base readings and previous
reading
REPORTING OF RSG
• A tabulated data and plot of thickness of fill and
settlement of plate against time.
• Detail result
RESULT FROM
TABULATED DATA
RESULT FROM
TABULATED DATA
• S.I is compulsory for every project.
• From S.I. result, engineer can design the best solution
to improve ground condition in effective and
economic approached.
• Must know 2 W, 1H
CONCLUSION