2016年06月12日

Established tool-Soil nail

Many years of experience covering a wide range of mining methods and conditions make us confident that we can provide practical and implementable solutions to your rock mechanics and strata control problems in both hardrock as well as slope foundation - from sophisticated design using advanced numerical modelling tools to the quality assessment of support design and installation.
The soil nailing system of Sinorock has become an established tool in the industry for mining.Through innovation we have developed the simple and very effective system for supporting the foundation pit in inaccessible places. Our expertise has stood us in well stead in a number of major long-term research projects.
Soil with low shear strength, tensile strength almost can be ignored, but the soil has a certain structural integrity. When excavation of foundation pit, soil in the critical height of slope is in an upright position, when more than the depth or overload on the ground and under the effect of other factors, the sudden overall damage will occur. Traditional retaining structure are based on passive restriction mechanism. Namely by its own strength and stiffness, bear the following lateral earth pressure, prevents damage to the overall stability of soil. Soil nailing is set in soil body with a certain length and density of soil nailing, work together with the soil and make up for a lack of tensile and shear strength of soil itself. Soil nailing and soil work together to form a composite soil that can greatly increase the strength and stiffness of the undisturbed soil. Experiment shows that the vertical carrying capacity of the soil nailing wall in the top about one times more than a plain wall. More importantly, soil nailing structure is recognized as a good ductile characteristics.

Loaded during prime soil slope does not occur as sudden landslide, slope provides for the repair time, and reduce the loss caused by the slope of the slump.
http://soilnailing.over-blog.com/2016/06/sinorock-provides-expert-soil-nailing-support-for-civil-engineering-projects.html  

Posted by soilnailing at 18:19Comments(0)TrackBack(0)

2016年06月07日

Soil nails for stabilization

Soil nailing is used primarily for excavation support or slope stabilization. This process involves the installation of closely spaced soil nails drilled near horizontal and the application of a facing material such as reinforced shotcrete or structural mesh. The soil nails themselves tend to be small in diameter, typically 4″ to 6″, and consist of a center reinforcing bar surrounded by grout. Soil nail spacing usually ranges from 4′ to 6′ on center vertically and horizontally with the top row of soil nails generally being placed in the upper two feet of the excavation or slope.
From a design standpoint, soil nailing is a passive system attempting to place enough anchorage into the adjacent soil so it acts as a “reinforced block” to resist overturning. The load demand on each nail tends to be fairly low as they are intended to act as a group. In the case of excavation support, the facing is usually designed to take little load but more so tie the system together. In the case of slope stabilization, the facing may be designed to take more load and the nails may be post tensioned.
Advantages:
Soil nailing is generally faster and more cost effective than other excavation support methods.
Nail locations can easily be adjusted in the field if obstructions are encountered.
Soil nailing can be designed for temporary or permanent applications.
Shotcrete facing can be carved and stained to provide decorative finish options.
Soil nailing can be installed with relatively small equipment
Disadvantages:
Soil nailing is not well suited for applications below the ground water table
Soil nails may require permanent underground easements
Adjacent underground utilities can be a problem
Soil nail walls are less rigid than other methods and therefore may require underpinning of adjacent structures
Applications:
Temporary excavation support
Permanent excavation support
Slope stabilization
http://news.scoopasia.com/index.php/news/introduction_about_typical_soil_nails  

Posted by soilnailing at 17:33Comments(0)TrackBack(0)

2016年05月26日

Fixed condition - Soil nail

Soil nailing is a technique used to reinforce and strengthen existing ground. Soil nailing consists of installing closely spaced bars into a slope or excavation as construction proceeds from top down. It is an effective and economical method of constructing retaining wall for excavation support, support of hill cuts, bridge abutments and high ways. This process is effective in cohesive soil, broken rock, shale or fixed face conditions.
Due to the number of construction increaseing , it had a strong focus on self drilling soil nail . And this phenomenon has an impact on Sinorock,so Sinorock devoted more on the self drilling soil nails manufacturing.
Self drilling soil nail are fully threaded drill rods with drill bits which will advance the self-drilling anchor bolt into the required depth. The self-drilling hollow bar anchor will be grouted in place, which will create the steel reinforcing of an anchor. Self-drilling anchors can be used as tie down anchors, deep foundation, rock anchors, soil nails and micropiles in lots of difficult applications.
Self-drilling anchor is a valuable and multi-functional additions to engineers. With the use of Sinorock drill hollow bar, production rate is much improved, compared with solid bar anchors. Hole casing system can be avoided, especially in low headroom.  

Posted by soilnailing at 18:48Comments(0)TrackBack(0)

2016年05月24日

Soil nail for excavation


The technique of soil nailing began to evolve in the early 1970's. Major research programs in Germany in the mid to late 70's and in France in the late 80's advanced this method of construction. It has been successfully utilized worldwide for excavation support and slope stabilization and its use continues to grow rapidly.

Applying the principles of systematic rock anchoring to soil seems to be obvious, but the requirements for soil nailing are higher. The many years of experience gained with pressure-grouted anchors have resulted in a certain level of standards; however, the stability of the supported soil mass must be verified for all stages.Soil nails are used for stabilizing slopes and excavations. The soil nails are installed as the excavation progresses from top to bottom. The surface of the cut is usually stabilized by shotcrete and rebars mats. The anchoring length of the soil nails must extend into stable ground.
Rock Anchors are used to secure guys in solid rock or concrete.
A hole slightly larger than the diameter of the Anchor is drilled at 90° to the guy. The ribbed wedge is placed in the anchor slot and the anchor dropped to the bottom of the hole. Repeated blows with a heavy hammer cause the Anchor to expand against the side of the hole, holding it securely. For added security and prevention of frost action the anchor hole may be sealed with cement grout or sulphur.  

Posted by soilnailing at 16:42Comments(0)TrackBack(0)