Self Drilling Hollow Rock Bolt VS Casing Pipe, Which Is Better to Support Unstable Conditions?
Time:2022-05-19From:sinorock View:
When supporting the slopes, foundations, and tunnels, we usually use self drilling hollow rock bolts or casing pipes. If the condition is loose, broken, which is better? I prefer the former. Why? Let’s see it.What Is Self Drilling Hollow Rock Bolt?
There are six primary parts that construct a complete self drilling anchor rock bolt. They separately are a sacrificial drill bit, a fully threaded hollow steel bar, a coupler to continue the hollow steel bar if necessary, a plate and a nut to transmit the force from rock mass, a centralizer to ensure the hollow steel bar being at the central position of the drilling hole, and an alternative shank is required if the drilling rig has the percussion function.
Advantages of Self Drilling Hollow Rock Bolt
1. Hollow bolts are drill pipes, grouting pipes and bolts, no grouting pipes or exhaust pipes are required, and the construction equipment is simple;
2. The full-length bonding and anchoring is closely combined with the surrounding rock and soil, and the pulling force bearing capacity is larger;
3. The force value range of common bolts is 200kN-7940kN, and the selection range is wide;
4. The product can meet temporary or permanent support (galvanized);
5. There are many types of drill bits, which are suitable for a wide range of strata (sand soil-IV and V-level surrounding rocks);
6. Fewer personnel are required during construction, only three people are required, and the labor cost is low;
7. It can be used in special strata or strata with unknown geological conditions, and the effect of pore formation and force value is better than other bars;
8. The disturbance to the stratum during the construction process is small;
9. Grouting during drilling can properly expand the hole diameter and improve the bearing capacity of the drawing force;
10. The impact on the surrounding environment is small during drilling and construction, and almost no pollution is produced.
Construction Methods
Drilling first and then grouting:
Prepare the drilling rig, materials → install the bolt and drill bit → connect the bolt to the drilling rig, connect the compressed air or water pipe → drill → flush the hole → extend the bolt → drill → complete the drilling → connect the grouting pump → grouting → installation Backing plate, nut
Simultaneously drilling and grouting:
Prepare the drilling rig, materials → install the bolt and drill bit → connect the bolt to the drilling rig, grouting pump → drilling → flush the hole → extend the bolt → drilling → complete the drilling (grouting completed) → install the backing plate and nut
Usable Drilling Equipment
1. Down-the-hole drilling rigs and top-drive hydraulic rock drilling rigs
2. Anchor drilling rig rock drilling rig
3. Excavation and modification of drilling rig
4. Split drilling rig (electric and hydraulic)
5. Hand-held drilling rigs available below R32 specification
Drilling Speed in Different Rock
1. Silty clay---0.5min/m, the grouting pressure is 1MPa, the connection time is about 3min, and the water-cement ratio of the cement slurry is 0.5.
2. Round gravel, strongly weathered rock---1min/m, grouting pressure 0.3-0.5MPa, cement slurry water-cement ratio 0.5-0.55.
3. The surrounding rock of grade IV and grade V---0.5-1min/m, the grouting pressure is 0.4MPa, and the water-cement ratio of the cement slurry is 0.45.
4. Vc grade surrounding rock---shale 1min/m, mudstone 0.5min/m, grouting pressure 0.5-2.0MPa, cement slurry water-cement ratio 0.45.
Above all, I think the self drilling hollow rock bolt is a better way to support broken and loose conditions.
latest news
-
- How To Support The Tunnel Pass Through Cobble Layer? Self-drilling Anchor Bolt Support Method
- Time:2023-02-25From:This Site
- How to support the tunnel pass through cobble layer? Self-drilling anchor bolts can be used for support. It can solve the construction problems encountered when the tunnel passes through the cobble layer by drilling preparation, drilling and grouting, coupling the anchor bars, and pull-out test.
- View details
-
- What Is Soil Nailing?Stabilization of Slope in Loose Soil Using Soil Nails
- Time:2023-02-22From:This Site
- soil nailing system repair unstable natural slope, or build a new or existing ultra-steep slope with closely spaced steel inclusions. self drilling anchor bolts used as soil nails are widely used slope stabilization.
- View details
-
- 3 Types of Self Drilling Soil Nailing Construction Equipment
- Time:2023-02-18From:This Site
- In the traditional sense, steel bars are often used as soil nails, so the supporting construction equipment is relatively mature. So what construction equipment is there for self-drilling soil nailing? Next, Sinorock will introduce the equipment used for self-drilling anchor bolts as soil nails.
- View details
-
- Quality Control, the Vital Factor of A SDA Bolt Factory
- Time:2022-07-22From:This Site
- The self-drilling rock bolts are applied to support the tunnels, reinforce the foundations, and stabilize the slopes that are in bad conditions. The constructio
- View details
-
- Spring Day Celebrations
- Time:2021-04-30From:This Site
- In this spring season, do everything that makes us happy. In any case, we should enjoy life.
- View details
-
- A Meaningful Christmas Day - Decorating Christmas Tree with Colleagues
- Time:2020-12-25From:This Site
- The Christmas party is a staple of office life-a way for teammates to socialize in a non-work setting. We had a pleasant and meaningful day. We decorated the Christmas tree together.
- View details
-
- SINOROCK Will Attend CONEXPO-CON/AGG 2023
- Time:2023-02-14From:This Site
- CONEXPO-CON/AGG 2023 will be held during 3/14-3/18 2023. Sinorock will attend with our proud products self-drilling achor bolt system and other anchoring products. Welcome to visit!
- View details
-
- Sinorock is attending Philconstruct Manila 2022
- Time:2022-10-19From:This Site
- Philconstruct Manila 2022 will be held during 11/03-11/06 2022. Sinoroc will attend with our proud products self-drilling achor bolt system and other anchoring products. Welcome to visit!
- View details
-
- Sinorock Will Attend 2022 Bauma CTT Russia Expo Trade Fair in Mosco
- Time:2022-05-12From:This Site
- Sinorock will attend the 22nd Bauma CTT Russia Expo on May 24-27, 2022. Check the detail information below: Booth Number: Exhibition Hall 13, 528Address: Crucos
- View details