Types Of Slope Protection m71k

CIV 510.1: Bridge Engineering

SLOPE PROTECTION Presented by Group 6

Gio ALCA

Anne JAVELOSA

Jessa RANCES

Renzo ROLDAN

Louies UNGRIA

SOIL SLOPE

UNRESTRAINED SLOPE • is an exposed ground surface that stands at an angle with the horizontal • The slope can be natural or constructed

INSTRUMENTS USED IN SOIL SLOPE DETERMINATION

HAND LEVEL • for rough leveling work • useful for extending approximate elevations

INCLINOMETERS • measure horizontal displacements along various points on a borehole • ideally suited to long-term, precise monitoring of the position of a borehole over its entire length

EXTENSOMETERS • for rough leveling work • useful for extending approximate elevations

CLASSES OF SOIL SLOPE

DEFINITIONS OF SLOPE CLASSES

LAND SURFACE SHAPE

TWO COMPONENTS OF LAND SURFACE SHAPE 1. Direction roughly parallel to the contours of the landform 2. Direction perpendicular to the contours

LAND SURFACE SHAPE

Causes of Slope Failure

Erosion Loss of such interlocking significantly reduces the rock mass shear strength. The resulting decrease in shear strength may allow a previously stable rock mass to move causing slope failure.

Seepage Seepage forces in the sloping direction add to gravity forces and make the slope susceptible to instability. The pore water pressure decrease the shear strength. This condition is critical for the downstream slope.

Sudden Drawdown There is reversal in the direction flow and results in instability of side slope. Due to sudden drawdown the shear stresses are more due to saturated unit weight while the shearing resistance decreases due to pore water pressure that does not dissipate quickly.

Rainfall • Long periods of rainfall saturate, soften, and erode soils. Water enters into existing cracks and may weaken underlying soil layers, leading to failure, for example, mud slides.

Earthquakes • They induce dynamic shear forces. In addition there is sudden buildup of pore water pressure that reduces available shear strength.

External Loading • Additional loads placed on top of the slope increases the gravitational forces that may cause the slope to fail.

Construction Activities • at the toe of the slope: Excavation at the bottom of the sloping surface will make the slopes steep and thereby increase the gravitational forces which may result in slope failure.

RETAINING WALLS

What is a Retaining Wall? • Retaining walls are structures whose aim is to restrict the movement of soil at unnatural slopes (difference in elevation). They are being used for quite some time now and are a frequent sight in mountainous regions where roads have been built. Apart from that, retaining walls are also used to restrain water.

How does Retaining work?

Wall

• Different types of retaining wall work differently, however, the main consideration in deg and subsequently the working principle of a retaining wall is to overcome the pressure and moment being exerted by the entity that it is being used to restrain. For instance; if you’re restraining soil, there will be lateral earth pressure that is dependent on the angle of friction (phi) and the cohesive strength of soil. It is important to provide water pores so that hydraulic pressure can be relieved from the wall,

Retaining Wall

Types of Retaining Wall • Gravity • Cantilevered • Sheet piling • Anchored • Cellular Confinement • Soil nailing • Soil-strengthened • Gabion meshes • Mechanical stabilization

Types of Retaining Wall

Types of Retaining Wall

Types of Retaining Wall

Types of Retaining Wall

Applications Wall • Dams • Slope Stabilization • Mountain roads • Homes • Marine Works • High security Fencing • Protection of Culverts

of

Retaining

Precautionary Measures • Water Drainage Pores must be provided. • Factor of safety • Simulations should be run before construction. • Usually one method of retaining wall is not enough and you should combine 2-3 techniques to achieve the desired result. • Increase in height won’t increase the capability of retaining wall, rather it would decrease it.

TYPES OF SLOPE PROTECTION

Rock Slope Protection • Two Methods: • Method A: used where the stability of the rock slope protection is considerably dependent on the manner in which the individual rocks are placed. • Method B: is not restrictive with respect to the placement of individual rocks

Concreted-Rock Slope Protection • used where large rock is not economically available in large quantities, yet a heavy, service type of protection is required • involves constructing a heavy mass of smaller rocks bound together by concrete

Small-Rock Slope Protection • consists of excavating and backfilling the footing trench, placing rock slope protection fabric, and placing small rocks on the slope

Concrete Slope Protection • consists of paving the embankment with Portland cement concrete • adaptable to locations where highvelocity flow is not detrimental, but desirable, and the hydraulic efficiency of smooth surfaces is important

Broken-Concrete Slope Protection • consists of placing broken concrete from job site locations identified within the contract

Slope Paving • covers a variety of methods for paving slopes, including colored slope paving, exposed aggregate slope paving, and slope paving with concrete pavers.

Gabions • consists of placing wire mesh boxshaped baskets filled onsite with hard, durable rocks

Sacked-Concrete Slope Protection • used when a number of serious failures have occurred • failures are usually associated with the foundation or water getting behind the slope protection and “peeling off” the protection