SLOPE REPAIR

Slope stability/slope performance concerns most hillside property owners. Heavy winter rains resulting in saturated earth materials can cause slope failure, landslides, and settlement. If such an event occur, the Department of Building and Safety typically issues an "Order to Comply". This may require a repair, acceptable to the Grading Division, within a specified period of time. Mother Nature will typically try to reduce the gradient of most slopes, therefore, the steeper slopes are more prone to instability and problems. Recent erosion and/or tension cracks in the exposed soil, parallel to the contours, may be indicative of recent slope movement or may precede slope failure. Leaning trees and curved trunks indicating that the tree has tried to right itself during growth, may be indicative of a long-term soil movement process called "downhill creep."

Friction Piles. Friction piles may be used to prevent lateral movement and slope failure. The piles may be isolated and designed as soldier piles or provided with a panel or lagging and designed as a retaining wall. Lagging is placed between the piles as a barrier to act as a retaining wall to prevent the soil between the piles from moving downward.
Benching. Keying and Benching is required to properly repair a slope which has already failed and the earth materials are to be replaced as a part of the restoration. The new compacted fill must be keyed and benched (stepped) into the underlying competent material.
Geo-grid. Geo-grid is a heavy gauge plastic mesh used within layers of the approved compacted fill to strengthen the fill. The geo-grid is typically used to allow a steeper gradient slope than the maximum allowable 2:1 (26 degrees). Geo-grid is generally thought to be cost effective as retaining walls may be eliminated to create a larger level area.
Retaining Walls. Retaining walls are generally used to increase the size of a level pad area or for subterranean portions of a structure. Retaining walls less than 3 feet in height with a horizontal back slope are typically allowed within the City of Los Angeles, provided the standard engineering information provided by the City is used. Walls in excess of 3 feet high will require obtaining a Geologic and Soils Engineering Exploration report, survey, and structural engineering in order to obtain a permit.
Drainage. Each site has specific minimum drainage requirements. Concentrated drainage statistically results in erosion and slope failures. Poor drainage control is the most significant potential problem for hillside sites and the most preventable. It is best to have an engineering geologist perform a site visit to evaluate the drainage conditions to enhance the future site performance by providing drainage recommendations.
Shotcrete. Shotcrete has been used to stabilize slopes provided the slope face consists of bedrock. The Shotcrete is pneumatically applied over a grid of reinforcement bars which have been properly anchored to the slope. The City now requires a Geologic and Soils Engineering Exploration report, survey, and structural engineering in order to obtain a permit for the application. Shotcrete for slope stabilization is considered to be a remedial repair.

Sinai Construction can perform slope stabilization utilizing the most cost-effective and at the same time most effective approach. Our construction methods utilize the latest developments in engineering geology and engineering technology.

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