CHAPTER 2: DESIGN CRITERIA AND REVIEW OF RELATED LITERATURE

2.1 Preliminary Data

2.1.1 Topography
Rodriguez's average elevation is estimated at 112 meters, the highest elevation is 487 meters, and the
minimum is 13 meters. Its topography was usually regarded rough, with 83% of its complete land region
consisting of hill ranges, upland regions, and hills, while the other 17% low-lying land includes the Marikina
River Valley. The estimated altitudes range from 10 to 30 meters above sea level for these low lying
terrains. Most of the greater elevated water that drains to the Marikina River along with its tributaries in the
southwestern part of the city runs through Barangay San Jose and creates flooding during heavy rains. The
municipality's central and eastern areas are where the mountain regions can be discovered. Rodriguez,
Tanay, and Puray Rivers drained elevated altitudes including mountain slopes ranging from 30 to 50 %,
steep hills with slopes higher than 50 % and rolling slopes of 18 to 30 % to hilly regions.

27m

Figure 2-1: Topographic Map of Rodriguez, Rizal

(Source: topographic-map.com)
2.1.2 Demographic Profile of Barangays
The
BALITE POPULATION OF RODRIGUEZ, RIZAL
BURGOS (as of 2019)
GERONIMO
MACABUD
MANGGAHAN
MASCAP
PURAY
ROSARIO
SAN ISIDRO
SAN JOSE
SAN RAFAEL

municipality of Rodriguez has an estimated population of 459,485 in 2019, with Barangay San Jose as the
most populated barangay having 155,393 residents, according to the National Statistics Office (NSO). This
accounted for 33.82% of the total population of Rodriguez or 5.39% of the province's total population. The
population density is calculated at 2,662 residents per square kilometer or 6,893 per square mile. This was
presented to show how many residents will benefit from the project.

Figure 2-2: The Population of Rodriguez, Rizal

(Source: Municipality of Rodriguez Rizal)

2.1.3 Economy
Rodriguez's
Income (In Philippine Peso)

Annual Regular Income

550,000,000.00 annual
periodic
450,000,000.00
income in
350,000,000.00 2009 was
250,000,000.00 Php
150,000,000.00
50,000,000.00
2009 2010 2011 2012 2013 2014 2015 2016
Fiscal Year
73,233,157.70 and, as a result of added trade and commerce, reached Php 532,871,106.64 for the 2016
fiscal year, according to the Bureau of Local Government Finance.

Figure 2-3: Annual Regular Income

(Source: Philatlas.com)

2.2 Geotechnical Investigation Reports

In the soil investigation of borehole drilling up to 10 meters depth, two units of rotary, hydraulically operated
drilling machines, a TOHO and YBM designs with cathead attachment were used. The hole was developed
between sampling parts using S drill coring bit by the "wash-boring method." By driving a steel split-tube
sampler at defined concentrations, a standard penetration test or SPT was performed. Split-spoon sampler
mounted on an AW-size drill rod is driven to the ground by hammering from a 140-pound steel hammer
freely-falling from a height of 76 cm. The values of N recorded as the soil penetration resistance or the
number of blows needed to drive the sampler to the last 30 cm of penetration range. After the samples
retrieved are properly stored and sealed in a moisture-tight plastic bag for testing.

Table 2-1: Consistency Classification for Fine-Grained Soils

Classification SPT N-Value Undrained Shear Strength,
Su (kPa)
Very soft <2 <12
Soft 2-4 12-25
Medium 4-8 25-50
Stiff 8-15 50-100
Hard 15-30 100-200
Very Hard >30 >200
(Source: CORE Land Specialist and Dev’t. Co.)
Table 2-2: Consistency Classification for Coarse-Grained Soils
Classification SPT N-Value Undrained Shear Strength,
Su (kPa)
Very loose <4 0-15
Loose 4-10 15-35
Medium Dense 10-17 36-65
Dense 17-32 65-85
Very Dense >32 85-100
(Source: CORE Land Specialist and Dev’t. Co.)

2.3 Laboratory Testing

Selected soil samples were subjected to the following specific tests.

Figure 2-4: Laboratory Pictures

(Source: CORE Land Specialist and Dev’t. Co.)

2.3.1 Particles Size Analysis of Soils (ASTM D-422)

The size and amount of individual particles discovered in a specific soil are indicative of the soil's
performance characteristics. It records the proportion by weight of the material that passes through each
specific sieve.
2.3.2 Natural Moisture Content of Soils Test (ASTM D-2216)
The quantity of water in the sample is determined. To determine other soil parameters used for assessment
and design, the findings acquired here are used.

2.3.3 Atterberg Limits of soils (Liquid Limit, Plastic Limit, Shrinkage Limit, and Plasticity Index of Soils)
(ASTM D-4318, ASTM D-4943)
These are the moisture content at which soil changes at certain state behavior. From liquid to plastic,
plastic to semi-solid, semi-solid to solid. While the plasticity index is used to determine the distinction
between the limits of liquid and plastic, both are used to determine the classification of soil. To correlate
other soil parameters (e.g. Cc, Cr), all these parameters are used.

2.4. Subsoil Condition

Three (3) boreholes drilled at the site to determine the subsoil represented by the soil profiles. Type,
composition, and condition of the stratum are idealized into three (3) soil stratum, namely: Weak, Firm and
Hard.

2.4.1 Test Pit Soil Profile

 Borehole 1
The water table was encountered at 7 m below the ground surface.
Weak Zone - very soft/loose soils with an N-value of < 10 blows/ft. for sandy soils and < 8 blows/ft. for
plastic silts and clays.
Table 2-3: Borehole 1
Borehole No. Thickness (meter) Type and Condition of Material
BH-1 0.00-1.50 Non-plasticity, loose SILTY SAND (SM)
(Source: CORE Land Specialist and Dev’t. Co.)

Firm Zone - confined mainly at the upper to middle soil layers with N-values between 10 to 32 blows/ft. for
sandy soils and between 8 to 30 blows/ ft. for plastic silts and clays.
Table 2-4: Borehole 1
Borehole No. Thickness (meter) Type and Condition of Material
 BH-1 1.50-3.00 Low plasticity, stiff SILTY SAND (ML)
3.00-4.50 Non-plasticity, medium dense SILTY SAND (SM)
(Source: CORE Land Specialist and Dev’t. Co.)

Hard/Compacted Zone - located below the firm zone with N-values of > 32 blows/ft. for sandy soils and >
30 blows/ft. for plastic silts and clays.
Table 2-5: Borehole 1
Borehole No. Thickness (meter) Type and Condition of Material
4.50-6.00 Non-plasticity, dense SAND WITH SILT (SW-SM)
6.00-7.50 Non-plasticity, very dense WELL-GRADED SAND (SW)
BH-1 7.50-10.00 Non-plasticity, very dense POORLY-GRADED SAND
(SP)
(Source: CORE Land Specialist and Dev’t. Co.)

 Borehole 2
The water table was encountered at the ground surface.
Weak Zone - very soft/loose soils with an N-value of < 10 blows/ft. for sandy soils and < 8 blows/ft. for
plastic silts and clays. No weak zone was encountered in this borehole.
Firm Zone - confined mainly at the upper to middle soil layers with N-values between 10 to 32 blows/ft. for
sandy soils and between 8 to 30 blows/ ft. for plastic silts and clays. No firm zone was encountered in this
borehole.
Hard/Compacted Zone - located below the firm zone with N-values of > 32 blows/ft. for sandy soils and >
30 blows/ft. for plastic silts and clays.
Table 2-6: Borehole 2
Borehole No. Thickness (meter) Type and Condition of Material
0.00-1.50 Non-plasticity, very dense CLAYEY SAND (SC)
1.50-3.00 Non-plasticity, very dense SILTY SAND (SM)
3.00-4.50 Non-plasticity, very dense WELL-GRADED SAND
(SW)
BH-2 4.50-6.00 Non-plasticity, very dense POORLY-GRADED SAND
(SP)
6.00-7.50 Non-plasticity, very dense POORLY-GRADED SAND
WITH SILT (SP-SM)
7.50-10.00 Non-plasticity, very dense POORLY-GRADED SAND
(SP)
(Source: CORE Land Specialist and Dev’t. Co.)
 Borehole 3
The water table was encountered at 3 m below the ground surface.
Weak Zone - very soft/loose soils with an N-value of < 10 blows/ft. for sandy soils and < 8 blows/ft. for
plastic silts and clays.
Table 2-7: Borehole 3
Borehole No. Thickness (meter) Type and Condition of Material
BH-3 0.00-1.50 Non-plasticity, loose SILTY SAND (SM)
(Source: CORE Land Specialist and Dev’t. Co.)

Firm Zone - confined mainly at the upper to middle soil layers with N-values between 10 to 32 blows/ft. for
sandy soils and between 8 to 30 blows/ ft. for plastic silts and clays.

Table 2-8: Borehole 3

Borehole No. Thickness (meter) Type and Condition of Material
BH-3 1.50-3.00 Non-plasticity, medium dense WELL- GRADED
GRAVEL WITH SILT (GW-GM)
(Source: CORE Land Specialist and Dev’t. Co.)

Hard/Compacted Zone - located below the firm zone with N-values of > 32 blows/ft. for sandy soils and >
30 blows/ft. for plastic silts and clays.
Table 2-9: Borehole 3
Borehole No. Thickness (meter) Type and Condition of Material
BH-3 3.00-6.00 Non-plasticity, very dense WELL-GRADED SAND
WITH SILT (SW-SM)
6.00-7.50 Non-plasticity, very dense SILTY SAND (SM)
7.50-9.00 Non-plasticity, hard SANDY SILT (ML)
9.00-10.00 Non-plasticity, very dense SILTY SAND (SM)
(Source: CORE Land Specialist and Dev’t. Co.)

2.4.2 Foundation Design

A Shallow type of foundation systems such as combined footings and strips should be used based on the
laboratory test outcomes. The Mat Foundation, however, is suggested if the foundation scheme for financial
purposes occupies 50% of the overall structure footprint. Dewatering equipment is required for a foundation
during excavation as there is water present at the shallow level. The recommended foundation must be 3
meters below the surface of the ground where materials are compacted. The weak zones usually on the
upper levels should be avoided as a foundation. Shallow foundation can be employed at 3 meters depth.
Overall, the test found out that the soil is not susceptible to liquefaction.

2.4.3 Subsurface Conditions

The boreholes showed gravel and cobbles layers of sand. The shallow layer is made of medium dense to
dense grayish-brown gravel (GM) from the ground surface to two (2) meters deep. A layer of dense gray
sands underlines this. The lower layer comprises dense cobbles and gravels until the borehole reaches the
depth of fifteen (15) meters. The Standard Penetration Test (SPT) N-value varies from 20 until refusals.
The natural humidity content ranged from 11% to 30% of the soil samples retrieved from non-plastic to 5%
with plasticity indexes. The groundwater table after field investigation is noted at a depth of three (3)
meters.

2.4.4 Soil Bearing Capacity

 BH-1: Has a loose silty sand soil profile on the topmost 1.50 meters, underlined by the steep to medium
dense sandy silt to silty sand down to 4.50 meters. The material below to the bottom of the hole is
occupied by a hard compacted zone, consisting of dense to very dense sand. There's no liquefaction.
The ultimate soil bearing capacity Qu varies from 95.022 kg/m2 to 185.030 kg/m2 at a depth of 3.00 m.

 BH-2: The soil profile from the top down to the bottom of the hole, is a very dense material. There's no
liquefaction. Qu's ultimate soil bearing capacity varies from 109,006 kg/m2 to 185,030 kg/m2.

 BH-3: Has a thin soil profile of loose silty sand at the topmost 1.50 meters and medium dense gravel at
1.50 meters and 3.00 meters. Under 3.00 meters there is a very dense hard compacted zone with a silt
layer down to the bottom of the hole. There's no liquefaction. The ultimate soil bearing capacity Qu
varies from 135.838 kg/m2 to 185.030 kg/m2 at a depth of 3.00 m.
 Computation of Soil Bearing Capacity
Boreho Dept N N C U. Wt. F N N N Fc Fq Fγ W L Qa Qu Material
le No. h ’ Kg/ (kg/m de c q γ (m (m (kg/m (kg/m Descriptio
m2 3) g ) ) 2) 2) n
BH-1 1.50 8 8 300 1597 10 9 3 1 1.0 1.0 1.0 2.0 2.0 13,52 35,78 Silty
0 0 0 0 0 0 5 4 Sand
3.00 9 9 300 1597 12 9 3 1 1.0 1.0 1.0 2.0 2.0 17,51 42,97 Sandy
0 0 0 0 0 0 7 0 Silt
4.50 1 1 400 1756 16 1 5 2 1.0 1.0 1.0 2.0 2.0 36,94 95,02 Silty
7 6 0 3 0 0 0 0 0 2 2 Sand
6.00 3 2 400 1916 16 1 5 2 1.0 1.0 1.0 2.0 2.0 45,43 113,3 Sand
3 4 0 3 0 0 0 0 0 5 12 w/Silt
7.50 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 59,81 162,6 Well-
0 3 0 8 0 0 0 0 0 3 70 grained
sand
9.00 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 65,40 176,0 Poorly
0 3 0 8 0 0 0 0 0 3 86 -grained
sand
10.0 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 69,13 185,0 Poorly
0 0 3 0 8 0 0 0 0 0 0 30 -grained
sand

BH-2 1.50 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 37,45 109,0 Clayey
0 3 0 8 0 0 0 0 0 3 06 Sand
3.00 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 43,04 122,4 Silty
0 3 0 8 0 0 0 0 0 3 22 Sand
4.50 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 48,63 135,8 Well-
0 3 0 8 0 0 0 0 0 3 38 Graded
Sand
 6.00 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 54,22 149,2 Poorly-
0 3 0 8 0 0 0 0 0 3 54 Grained
Sand
7.50 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 59,81 162,6 Poorly-
0 3 0 8 0 0 0 0 0 3 70 Grained
Sand
9.00 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 65,40 176,0 Poorly-
0 3 0 8 0 0 0 0 0 3 86 Grained
Sand
10.0 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 69,13 185,0 Poorly-
0 0 3 0 8 0 0 0 0 0 0 30 Grained
Sand

BH-3 1.50 4 4 205 1597 7 7 2 0 1.0 1.0 1.0 2.0 2.0 7,977 109,0 Silty
0 0 0 0 0 0 06 Sand
3.00 1 1 400 958 16 1 5 2 1.0 1.0 1.0 2.0 2.0 24,67 122,4 Well-
7 6 0 3 0 0 0 0 0 8 22 Graded
Gravel
4.50 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 48,63 135,8 Well-
0 3 0 8 0 0 0 0 0 3 38 graded
sand
6.00 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 54,22 149,2 Well-
0 3 0 8 0 0 0 0 0 3 54 graded
sand
7.50 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 59,81 162,6 Silty
0 3 0 8 0 0 0 0 0 3 70 Sand
9.00 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 65,40 176,0 Sandy
0 3 0 8 0 0 0 0 0 3 86 Silt
10.0 5 3 500 1118 20 1 8 5 1.0 1.0 1.0 2.0 2.0 69,13 185,0 Silty
0 0 3 0 8 0 0 0 0 0 0 30 Sand

Table 2-10: Computation of Soil Bearing Capacity

2.5 Soil Properties

Here are the results of the Unified Soil Classification System (USCS) to describe the texture of the soil and
grain size.
Table 2-11: Fined Grained Soils
Highly Fine-Grained Soils 50% or more passes No.200 sieve Major
Organic Divisions
Soils
Silts and Clays Liquid Limit > 50 Silts and Clays Liquid Limit 50%or <

PT OH CH MH OL CL ML Group
symbols

Muck, Organic Fat clays, Organic silts Gravely Silty,roc Typical

peat, clays of inorganic Fine sands or clays of Low clays, k flour , names
 highly medium to clays of high silts, organic silt plasticity, sandy clays very fine
organic high plasticity diatomaceous, organic silts , silty clays, sand,
soils plasticity elastic silts lean clays, inorgani
inorganic c silts
clays of low
to medium
plasticity
(Source: CORE Land Specialist and Dev’t. Co.)

Table 2-12: Coarse-Grained Soils

Coarsed – Grained soil > 50 % retained on no. 200 sieve Major
Sands > 50 % of coarse fraction passes no.4 sieve Gravels 50% or more of coarse fraction divisions
retained on no. 4 sieve

Sands with fines Clean sands Gravels with fines Clean gravel
SC SM SP SW GC GM GP GW Group
symbols

Sandy Sand No fines, No fines or Gravel- Gravel- No fines Gravel Typical

clay dilt,silty gravely little, well sand sand silt , or sand, no names
mixture sand sands, graded clay,clay silty gravel little,grav fines or
s, poorly sands ey el snad, litlle, well
clayey gravely ,gravely gravel poorly graded
sands sands sands graded gravels
gravels

(Source: CORE Land Specialist and Dev’t. Co.)

2.6 Recommended Seismic Design Criteria

The site is approximately 1.8 km away from the West Valley Fault, a Type A seismic earthquake generator
which means it is capable of producing magnitude 7 or higher on its active phases. Due to the proximity of
the site to West Valley Fault, a Peak Ground Acceleration of 0.4 g is recommended. According to the data
provided by the DPWH Rizal II District based on NSCP Code Provision (2010) for earthquake designs of
m
structures, the site has a soil profile type S E which means the soil is soft, has less than 180 shear wave
s
velocity, with less than 15 blows per 300mm SPT and undrained shear strength of less than 50 KPa. The
near-source factors are N a = 1.5 and N v = 2.0, and the seismic response coefficients are C a= 0.44 N a, and
C v = 0.96 N v . This site falls in Seismic Zone 4, having Z = 0.4.
 Legend:
- 1.8 km west

WEST VALLEY FAULT

1.8 KM WEST

2.7 Review of Related Literature and Studies

This section covers the foreign literature, foreign studies, local literature and local studies related to the
target trade-offs of this capstone design project. It shows the different writings that compromise by some
published materials including research journals, experiment investigation reports and other local
researches which are important to support the development of the project.
2.7.1 Foreign Literature
2.7.1.1 Optimum Design of Cantilever Retaining Walls Linear Elastic Backfill by Use of Genetic Algorithm
According to George Papazafeiropoulos, Vagelis Plevris, and Manolis Papadrakakis et. al (2013),
Cantilever walls are among the simplest and most common geotechnical structures designed to support

Figure 2-5: Seismic Map of Rodriguez

(Source: PHIVOLCS and Google Map)
earth backfills. Holding walls supporting deep excavations, bridge abutments, harbor-quay walls, supported
stone walls, etc. are their primary members. Two major requirements must be satisfied by their design:
internal and external stability. The former ensures the structural integrity of the various parts of the retaining
wall; the latter ensures that, except for certain displacements of manageable magnitude, the wall-soil
structure created after construction will remain in equilibrium.
2.7.1.2 Geotechnical Approaches for Slope Stabilization in Residential Area
According to N. Mizal-Azzmi and N. Mohd-Noor et. al (2011), Even though the Retaining wall is generally
more costly, this method is still the most commonly used due to its principle. A principle that is to use a
retraining structure to resist the downward forces of the soil mass. The retaining structures include gravity
types of retaining wall, cantilever wall, contiguous bored piles, cassion, and steel sheet pile. Ground
anchors or other tie back systems may be used together with the retaining structures if the driving forces
are too large to resist. This method also involves rigid sloped surface protection such as shotcrete,
masonry and stone pitching. Shotcrete is applying mortar on a sloped surface by a certain thickness. To
eliminate the failure at face slope, masonry and stone pitching may stabilize the slope. It also may prevent
slope erosion of the slope forming materials and reduce rainwater infiltration. A slope will be relatively
stable when its profile (section angle) is kept below its angle of repose. The angle of repose is an angle that
maintains naturally to a safe equilibrium by the composing material of a slope. This angle deviates from
differing materials depending on compaction, particle size and the nature of the material itself.
2.7.1.3 Probabilistic Assessment of Liquefaction Initiation Hazard
The reliability analysis developed over the years starting from probabilistic methods, and some of the
studies are discussed as follows. Fardis and Veneziano et. al (1981) developed a probabilistic model using
the results of 192 published cyclic simple shear tests based on a statistical analysis of the liquefaction
potential of sands, taking into account the uncertainties caused by the effect of sample preparation, the
effect of system compliance and stress non-uniformities. Hwang and Lee et. al (1991) considered
uncertainties in both site per meter and seismic parameters to determine the liquefaction probability index,
PL, based on the SPT N-value which calculates the magnitude of liquefaction. Low et. al (2005) analyzed
for overturning and sliding the retaining walls.
2.7.1.4 Comparison of Pseudo-static and Pseudo-dynamic Methods for Seismic Earth Pressures on
Retaining Wall
Choudhary et. al (2006), compare the Pseudo-Static and Pseudo-Dynamic Methods for the Pressure of the
Seismic Earth on Wall and the study and contrast between these two methods reveals that the time-
dependent non-linear pressure distribution behavior obtained by the pseudo-dynamic approach results in
more practical earth stress model values under seismic conditions.
Tafrehi and Nouri et. al (2008) come to study the pseudo-static methods for evaluating the soil's thrust on
retaining wall under earthquake condition by establishing a new approach that specifies that the main
difference with conventional solutions is that the wall's occurrence is considered in the equilibrium
equations.
2.7.1.5 Slope Stability and Sheet Pile and Contiguous Bored Pile Walls
H. Niroumand et. al (2012), Sheet piles are widely used in the construction industry as a retaining structure.
Sheet piles often used to construct a retaining structure where the water table is high and to prevent water
from entering the construction site which can cause problems. Sheet pile walls can be designed based on a
cantilever system or anchored system. In practice, Sheet pile walls are constructed either driven a steel
sheet into the ground and then backfill is placed on the land side or driven a sheet into the ground and soil
in front of the system is then dredged. Generally, several types of sheet piles are used in the construction
industry they are wooden sheet piles, pre-cast concrete sheet piles, and steel sheet piles. However, steel
sheet piles are commonly used in Malaysia because of their resistance to high driving stress developed
when being driven into hard soils and them also lightweight and can be reused.
2.7.1.6 The Analysis Stability of Retaining Wall
According to Benarama Fatima Zohra and Belabed Lazhar et. al (2011) in “The Analysis Stability of
Retaining Wall” The rule is to reduce the slide's active forces and increase the normal stress on the surface
of the rupture. So it was anchored tied-back (constituted by steel cables) in the stable ground beneath the
surface of the failure and a traction force is applied at the top. Modeling the slope used to test the
measurement techniques, like FEM, as the basis for the carriageway, which was the object of several
repairs when the landslide occurred. Taking into account the hydro-mechanical coupling, the effect of shifts
in groundwater and the soil bar (anchor) the calculations presented were carried out. The study is based on
in situ and laboratory test calculation parameters. Increasing the internal circulation of water snow can
affect the balance of natural geological slope by dissolving gypsum, thus creating a drainage system
contributes significantly to the slope's stability.
2.7.1.7 Stability Analysis of Composite Soil-nailed Wall with Prestressed Anchors
According to Xiao Qiang Wu et. al (2015), the anchor rod retaining wall with material province covers an
area of less, construction is convenient wait for a characteristic, bolt on the slope of small disturbance,
prestressed anchor rod to control the deformation of the structure, etc, with the further development of the
anchor technology, the anchor rod retaining wall in railway, highway subgrade engineering and
architectural engineering will get the more extensive application in geotechnical engineering.
2.7.1.8 Soil Nail Wall Design
For shotcrete rock outcrops, sprayed concrete can be applied to the exposed surfaces immediately after
excavation when ground conditions are low, particularly in free-formed tunnel linings or retaining walls.
Shotcrete is usually used in these cases in combination with rock bolts and wire, thereby protecting the
loose material which causes many of the small ground drops. On the other hand, for both technical and
economic reasons, contractors want to determine the thickness and volume of sprayed concrete: to
guarantee their structural strength, but also not to supply excess material for which they will not be paid. In
this paper, we first introduce a LiDAR-based terrestrial method for automatic rock bolt detection, as is
typically used in anchored retaining walls. These ground support elements are segmented based on their
geometry and will serve as control points for two successive scans before and after shotcrete to be co-
registered. Martanez-Sanchez, J., Puente, I., Gonzalez Jorge, H., Riveiro, B. and, Arias, P. et. al (2016)
2.7.1.9 The Shape of Slide Surface of Gravity Retaining Walls Construction on Sand by Small Scale
Sinusoidal Dynamic Load Tests
According to Anissa Maria Hidayati, Sri Prabandiyani RW and I Wayan Redana et. al (2015), the following
conclusions could be drawn based on the experimental results obtained and discussed in this paper: The
increase in vibration frequency induces both an increase in the angular frequency trajectory and the overall
vibration acceleration. Increasing the vibration frequency with a specific amplitude and the sand density on
the model tests causes the area of landslides to increase. The increase in sand density with a specific
amplitude and the vibration frequency on model tests causes the landslide region to decline. Increasing the
amplitude and vibration frequency but with a particular amount of sand density on the model, tests cause
the area of landslides to increase.
2.7.1.10 Seismic Displacement of Gravity Retaining Walls
According to Kamal Mohammed Hafez Ismail Ibrahim et. al (2015), Gravity retaining walls with inclined
positive back slope surface experience greater total sliding and rocking displacements than vertical back
walls due to increased horizontal backfill mass and inertia. Some numerical seismic displacements are
approximately equal to those determined by the pseudo-static method for studied historical ground motions,
and others are comparatively larger. The accumulated seismic rotation of the wall gradually increases with
dynamic time and reaches the limit at the end of the earthquake.
2.7.1.11 Seismic Design of Gravity Retaining Walls
According to Hasan Chikh Mohamad et. al (2006), the seismic architecture of retaining walls has an
inherited over strength. The approximate fair value of the element of over strength is 1.55. Using 1.55
overstrength will preserve consistent performance across various parts of the country, which will contribute
to improved results in the safety standard for retaining walls. Based on the proposed values of the over
strength factors the efficiency of the seismic design of the retaining wall is close to resisting an event of
1500 years. An over strength factor equal to 1.55 can be used for design compatible with safety level with a
safety factor of 1.5 on the work stress approach.
2.7.1.12 Design and Analysis of Reinforced Earth Retaining Wall under Vertical and Horizontal Strip Load
According to Oliver King Tai et. al (1985), the experimental results indicate that the possible failure plane
formed in the reinforced earth system may well be approximated by the failure plane obtained by
Culmann's method due to vertical strip load placing within the Ranking failure wedge. The magnitude of
stresses produced in the reinforcing elements determined from the French Ministry of Transport method
and the Tensor method is not comparable to the stresses obtained from the experimental results when
applying the horizontal strip load towards the wall face.
2.7.1.13 Behavior of Retaining Wall
The author of this study, S. Abid Awn et. al (2014), concluded that the following hopping points were useful
for the student concerned: Results revealed that the movement of retaining wall through testing is not
standardized. By this, it means that retaining wall can fill forward or backward, settle in toe faster than heel
or the other way around. The vertical and horizontal motions are completely random, owing to the irregular
settling of the wall standing on the soil of gypsies. For the retaining wall model, the increase in rotation
settlement and collapse reaches more than 89 percent, achieved after-treatment of the embedded gypsum
soil layer with cement dust of 2.7 percent.
2.7.1.14 Study of Retaining Walls
Retaining walls isn't a new concept. Walls used to preserve soil masses have been around for thousands of
years, and have been used in almost every culture in history. Geotechnical engineering is a branch of civil
engineering that deals with soils as engineering materials; a retaining wall is any geotechnical structure that
is used to hold a mass of soil that would otherwise appear to slope down due to gravity and stresses that
acting within the soil. Terzaghi et. al (1996)
2.7.1.15 Two Classification of Retaining Walls
There are typically two classifications of retaining walls: externally stabilized walls that use heavy materials
to prevent soil movement on the outside of the soil mass, and internal stabilized walls that use artificial
supports mounted in the soil to support tensile loads and stabilize soil mass. Khan and Sikder et. al (2004)
2.7.1.16 Gravity Retaining Wall
Gravity Retaining Wall is a general term for walls that use the wall's self-weight to support the ground
behind the wall, called backfill, which may be undisturbed natural soil or disturbed soil that is placed behind
the wall and compacted. Gravity walls are a classic example of a balanced external wall structure. The
walls are built using heavy materials which must be adequate to withstand 5 from the soil mass to the
vertical and lateral stresses exerted on the wall. Criag et. al (1992)
2.7.1.17 Overview of the Design of Gravity Walls
Gravity walls have a rigid face while walls of GRS have a flexible, non-load bearing face. This is because
the lateral earth pressure in GRS walls is confined within each layer of reinforcement, called bin pressure,
thus lateral earth pressure on the face does not increase with depth. Michael White et. al (2011)
2.7.1.18 Behavior of Three Components in Soil Nailing
In a soil-nailed retaining wall, the properties and material behavior of three components—the native soil,
the reinforcement (nails) and the facing element—and their mutual interactions significantly affect the
performance of the structure. The behavior of reinforced soil walls can be understood to some extent by
studying the state of stress within the reinforced zone. Also, various factors such as the construction
sequence, the installation of nails, the connection between the nails and the facing are likely to influence
the behavior and a few case studies and analysis results are available (Murthy et al. 2009, Babu, et al.
2009, Babu, et al. 2010).

2.7.1.19 Soil Nails

Soil nail walls are particularly well suited to excavation applications for ground conditions that require
vertical or near-vertical cuts. They have been used successfully in highway cuts; end slope removal under
existing bridge abutments during underpass widening; for the repair, stabilization, and reconstruction of
existing retaining structures; and tunnel portals. Soil nail walls can be considered as retaining structures for
any permanent or temporary vertical or near-vertical cut construction, as they add stabilizing resistance in
situations where other retaining structures (e.g., anchor walls) are commonly used and where ground
conditions are suitable. The relatively wide range of available facing systems allows for various aesthetic
requirements to be addressed. In this application, soil nailing is attractive because it tends to minimize
excavation, provides reasonable right-of-way and clearing limits, and hence, minimizes environmental
impacts within the transportation corridor. G.L. Sivakumar Babu et. al (2009)

2.7.1.20 Ground Anchors

Ground anchors consisting of cables or rods connected to a bearing plate are often used for the
stabilization of steep slopes or slopes consisting of softer soils, as well as the enhancement of
embankment or foundation soil capacity, or to prevent excessive erosion and landslides. The use of steel
ground anchors is often constrained by overall durability in placement (due to weight), and the difficulty in
maintaining tension levels in the anchor. Anchor systems fabricated from fiber-reinforced composite
materials show some benefits compared to conventional systems for the following reasons. First, anchors
enhanced durability including resistance to corrosion and resistance to alkalis and solutions in soils
increase their life and greatly reduce the need for maintenance, thereby decreasing life-cycle costs.
Second, lighter weight results in easier transportation of cables to the site and increases the efficiency of
handling and placement. Lastly, anchors enhanced tensile strength coupled with lighter weight and
enhanced mechanical properties results in greater safety during installation in areas with limited clearance.
WTEC Hyper-Librarian et. al (1999)
2.7.1.21 Granular Pile Anchor
According to Anthony and Alice Tang et. al (2016), the use of granular pile is one of the effective and
efficient methods of ground improvement because of its ability in improving the bearing capacity and
reducing the settlement of different soft soils. Conventional granular piles cannot be used as tension
members to offer resistance under pull out loads. Granular Pile Anchor (GPA) is one of the recent ground
improvement techniques in devised for resisting pull out forces. In a granular pile anchor, the footing is
anchored to a mild steel plate placed at the bottom of the granular pile through a reinforcing rod or a cable.
2.7.1.22 Pullout Capacity of Vertical Ground Anchor in Homogeneous Sand
According to Mohd Rafe Abdul Majid et. al (2011), vertical ground anchors are widely used in foundation
systems for structures that need pullout resistance such as transmission towers, lateral-resistant structures
such as sheet pile walls. The study outlined in this research concerned primarily the pullout capability of a
vertical ground anchor embedded in dry homogeneous sand. The predicted pullout capability formulae for
shallow and deep anchors in dry homogeneous sand are established using the semi-empirical method, i.e.,
prediction of pullout test surface failure and analytical process. Results from the analysis show that the
formula predicted has a similar trend with previous studies and experimental testing.
2.7.1.23 Under reamed Ground Anchors
According to Richard H. Bassett et. al (2017), ground anchors are becoming increasingly necessary for
both cohesive and non-cohesive soils to support retaining walls. For compact soils, the effectiveness of the
carrying ability of an anchor is strengthened by the creation of under reams on the shaft. Empirical formulae
have been developed from the piling theory for calculating their load capacity. The paper discusses the
following characteristics of under reamed anchors using guided laboratory experiments: The effect of under
ream spacing, the influence of the amount of under reams and the relationship between the stiffness of the
soil and the stiffness of the anchor tendons. The observed fracture mechanisms indicate that the empirical
formula format is justified, and values are suggested for constants in nature.

2.7.1.24 Pullout Behavior of Vertical Ground Anchor in Dry Homogeneous Sand at Different Relative
Densities
According to Mohd Rafe Abdul Majid, and Ideris Zakaria et. al (2012), the findings showed that the pullout
behavior was affected by the density and depth of the embedded homogeneous sand. The findings also
showed that the pullout resistance behavior follows a similar curve until it reached a peak transition point
where the breakout factor pattern diverged, affected by the embedding depth and homogeneous density of
the soil.
2.7.1.25 The Load Displacement Behavior of Ground Anchors in Fine-Grained Soils
According to Juraj Chalmovsky, and Lumir Mica et. al (2018), In the field of geotechnical engineering
ground anchors represent a significant structural feature. Despite their extensive use, a process of
designing these elements is usually carried out using simple empirical and semi-empirical methods,
neglecting many important factors that influence them. First, the finite-element approach is used in
conjunction with a model of material involving regularized strain softening. First, an experimental system
was carried out including multiple anchor load studies of the investigation. The purpose of this program was
to confirm tentative conclusions drawn from numerical studies and to collect relevant data for further study
of the backup. Afterward, a newly developed framework based on the load transfer method is defined,
which integrates all the results from numerical computations and experimental measurements.
2.7.1.26 Numerical Studies on Progressive Failure of Ground Anchors
According to Laura Watzlik et. al (2015), To conclude, the goal of modeling progressive failure in extremely
overconsolidated clay at ground anchors is achieved. The MLSM reproduces intrinsically shear hardening
to peak shear strength and subsequent strain-softening to residual state. This causes the widely
acknowledged non-uniform shear stress distribution along with the interface between soil and grout. As the
height of this distribution moves along with anchor load increases towards the distal end of the anchor,
inherent dilatancy increases the stress that acts perpendicular to the grout surface. This entails an
improvement in both ultimate bearing capacity and residual anchor force, at which the residual angle of
friction is finally achieved.

2.7.2 Local Literature

2.7.2.1 An Assessment of the Efficiency of Retaining Structures along National Roads Leading to Baguio
City
According to Elman, M. et. al (2002) project of “AN EFFICIENCY OF RETAINING STRUCTURES ALONG
NATIONAL ROADS TO BAGUIO CITY retaining walls should be intended in line with soil mechanics
theories. Every slope has its soil characteristics so it should be closely designed for its building to retain
structures. Slope stability research of the soil to be protected would provide significant data that could
influence the composition of retention. It is necessary to accurately analyze the slope of retained earth in
coping with holding structures. Analysis of slope stability is used to determine whether a suggested slope
meets the necessary performance and safety requirements during design. The research typically requires
the following information: soil profile, soil geometry, soil shear strength, and water pressure from the pore.
This type of analysis is used to determine the stability of the slopes and to assess the proposed methods of
remediation if necessary.
2.7.2.2 Retaining and Reinforced Earth Wall Works
According to JICA et. al (2014) retaining walls are structures that support and retain earth to prevent
sediment failure in places where slope stability can not be guaranteed by ground conditions themselves or
other works of slope protection. Retaining walls have the following prospective applications: (a) to preserve
the stability of the foot portion of a path after being distressed, (b) to avoid small-scale shallow fall and toe
collapse of large-scale slope failures, (c) to promote slope fattening and berm filling, (d) to serve as a basis
for other slope protection works such as crib works, Catching rock fall mater to safeguard cars from falling
rock, and f) providing street room particularly where the right of manner is restricted.
2.7.2.3 Importance of Sheet Piles as a Better Option for Earth Retention Systems
According to ESC Group et. al (2010) sheet piles, soil nails, tangent walls, secant walls, shotcrete, soldier
piles, and wood lagging are the most prevalent techniques used. These structures can be either temporary
or permanent based on the building demands, and depending on the soil situation and wall height, they can
be either internally braced, tied back or cantilevered. Earth retention structures have developed from being
a comparatively easy earth support system-as used only for temporary shoring during excavation-to
becoming a complicated underground reinforcement used to stabilize slopes and profound cuts indefinitely.
Using sophisticated geotechnical building methods, state-of-the-art equipment, creative use of soil anchors
and soil nailing has allowed building employees to securely perform excavations using a cost-effective
technique.
2.7.2.4 Failures of Retaining Walls
Internal stability applies to the ability of the individual parts of the wall to act as a single unit. The wall has to
be designed so that the individual pieces of the wall do not pull-out, disconnect, or move apart. The internal
stability consideration for walls and soil is the potential for sliding between panels. External stability of
retaining walls must be designed to be stable concerning four potential external failure modes: global
stability, base sliding, overturning, and bearing capacity. Global stability refers to the firmness of the wall,
the soil at the back of it, and the soil beneath it. Base sliding refers to the outward movement of the bottom
of the retaining wall as a result of the lateral forces generated by earth pressure and, if present, water
pressure. The force resisting base sliding is the friction between the fill in the bottom layer and the
foundation soil beneath the bottom layer. Overturning refers to the tipping over of the retaining wall as it
rotates about the toe of the structure. While bearing capacity refers to the ability of the foundation soil to
support the weight of the retaining wall placed upon it. Failures of retaining walls are also attributed to
several factors like poor drainage, sloppy workmanship, inappropriate design, expansive backfill material,
etc. Thus, a carefully made and sustainable design is necessary for constructing a retaining wall that would
last for a long time. Elman, M. et. al (2002)