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Timber Crib cofferdam

5334 Crib cofferdams 53341 Timber crib cofferdams A timber

  1. 5.3.3.4 Crib cofferdams 5.3.3.4.1 Timber crib cofferdams. A timber crib cofferdam is formed by a framework of heavy timbers, either square or round in section, the timbers being laced together in criss-cross fashion to form pockets up to 3.5 m 2. Bolts, driftbolts, spikes and timber connectors may be used to connect the members, which should also be laced together in the vertical direction
  2. Crib is then sunk to the position, the bottom of each crib is given a shape to fit in the variation in the surface of bed rock. The space inside the crib is then filled with stone or any other material, so as to make it stable against sliding and overturning. Timber or steel sheet piles are then driven around the crib. Crib cofferdam
  3. Crib Cofferdams.—Timber cribs built on land and floated into position are frequently used as cofferdams, and for shallow depths, these may he made of a framework of timber with a covering of planks upon the outside. Usually the crib is formed of two walls. made of squared timbers laid on top of each other, tied together, and braced with.
  4. 4. Rock or Earthfill Timber Cribs. These are commonly constructed in a remote site in undeveloped areas where timber in bamboo or log form are available, and import and transfer of sheet pile and necessary plant to handle and drive it is astronomically high. 5. Timber Sheet Pile Cofferdam
  5. 3. ROCK FILL CRIB COFFERDAM:- Rock fill crib cofferdam is comprised of timber cribs. A crib is a framework of wooden horizontal cross beams laid in alternate courses. The cribs are open at the bottom and are filled with rock or gravel or earth. This gives stability to the crib against overturning or sliding

Cofferdam - Types of Cofferdam The Construction Civi

3. Crib or Braced Cofferdam: This types of cofferdam is made of a wooden cube. The crib is a framework made of wooden horizontal and cross beam alignment. The film is filled with stones, gravel, or clay to increase the stability of the crib against overturning or sliding. The following conditions are favorable for this types of cofferdam: Less. Timber Crib: Constructed on land and floated into place. Lower portion of each cell is matched with contour of river bed. It uses rock ballast and soil to decrease seepage and cofferdam and impacting on it under the action of waves. 3. Scour: Scour of the river bottom or seafloor along the cofferdam may take place owing to rive Fig: Cross-Section of Rockfill Cofferdam. Single-Walled Cofferdam This type of cofferdam is preferred when the depth of the water is more than 6m and area of construction is less. Usually this is used in construction of bridges. Wooden or timber sheets are driven into the river bed on the perimeter of the area of construction

The cofferdam is a temporary structure to exclude water from water-logged soil, river, or the sea to enable the excavation and construction to be carried out in the dry.Cofferdams are most commonly used to facilitate the construction or repair of dams, piers, and bridges. The cofferdam can be made out of the earth, concrete, sheet piles, or sheet cell timber crib, and (7) rock fill. Double wall cofferdam: Double wall cofferdams are somewhat permanent in nature and are built to last for few years. When construction work can take many years, single wall cofferdams may not be suitable. Single wall cofferdams leaks and dewatering is required on a regular basis. This problem can be avoided. (5) The Silverleaf weir was completed in 1953. The 5.1 m high timber crib structures was refurbished in 1995. During refurbishment, an earthfill cofferdam was built upstream to de-water the weir. A major flood event took place on the 7 February 1995 when the cofferdam was overtopped

All the timber/crib cofferdams were Ohio River Box type, which had been used extensively since the 1870s. These cofferdams were typically comprised of wood sheathing inside a frame of horizontal walers and tie rods. The cofferdams at No. 26 were constructed of steel sheet piling -Standard Handbook of Heavy Construction Types of Cofferdams Braced Earth-Type Timber Crib Double Walled Sheet Pile Cellular Braced Cofferdams Formed from a single wall of sheet piling Driven into the ground to form a box around the excavation site The box is then braced on the inside Interior is dewatered Primarily used for bridge piers in.

Cofferdams 197 - crib, bottom, sometimes, rock and leakag

  1. • It must be properly designed to resist lateral forces such as tipping / overturning and sliding 3. TIMBER CRIB 8. TIMBER CRIB COFFER DAM 9. • They are double wall cofferdams comprising two parallel rows of sheet piles driven into the ground and connected together by a system of tie rods at one or more levels
  2. Timber Crib Cofferdam Cellular-Type Cofferdam Constructed on land and floated into place Lower portion of each cell matched with contour of river bed Uses rock ballast and soil to decrease seepage and and sink into place Timber Crib Cofferdam (cont.
  3. The upstream cofferdam was needed to perform demolition of the instream structures, such as the portion of the old timber crib dam that was abandoned in place during installation of the RCC dam. NMC used hydraulic information from several sources to build the upstream cofferdam to the necessary elevation
  4. timber cofferdam, wood(en) cofferdam Holzfangedamm
  5. timber crib or rock filled crib cofferdams 14. It consists of timber cribs made from logs of wood Constructed on land and floated into place It consists of a unit or a cell open at the bottom and having the framework of horizontal timber members. Hollow space thus formed are then filled with rock or gravel Depth of water - 10 to 20 m Used for.
  6. Types of cofferdam: Braced Earth-Type Timber Crib Double-Walled Sheet Pile Cellular COFFERDAM COMPONENTS: • • Sheet piling • Sheet piling is a manufactured construction product with a mechanical connection interlock at both ends of the section

Cofferdam- Types, Selection Criteria, and Applicability

COFFERDAMS - civilengg-note

monitoring the behavior of the cofferdam and surrounding area provision of adequate access light and ventilation, and attention to safe practices on the part of all workers and supervisors. ATCEATCE-II -II Advanced Topics in Civil Engineering 5 Cofferdams Types of cofferdam: Braced Earth-Type Timber Crib Double-Walled Sheet Pile Cellula Types of Cofferdam. Single-walled cofferdam: This type of cofferdam is used in places where the area to be enclosed is very small and the depth of water is more, say 4.5 to 6 m Timber piles known as guide piles are first driven deep into the firm ground below the river bed. Depending upon the velocity of the current of the water in the river.

Coffer dam and its type

What Is Cofferdam Different Types Of Cofferdam Its Use

The massive 360-tonne crib lay at the bottom of the canal in 6.7 metres of water. Georgian Bay Shipbuilding and Wrecking, from Midland, was subcontracted to raise the crib. This was a challenging engineering project, requiring the construction of a large timber cofferdam that would be sunk over the crib Your permit calls for one cofferdam and I see 2...that's a violation of your permit. Earliest structure has precedence over later structures so...this metal one has to come down. 14. level 2. Ithappenedinflorida2. · 2y. I see you have experience in permitting LMAO. 3. level 1 Crib Walls. Crib walls are made up of interlocking individual boxes made from timber or pre-cast concrete. The boxes are then filled with crushed stone or other coarse granular materials to create a free-draining structure. There are two basic types of crib wall: - Timber, and - Reinforced pre-cast concrete

timber crib, wood(en) crib, timber bin (type) retaining wall, wood(en) bin (type) retaining wall [It consists of interlocking timber members used to stabilize slopes and protect road cuts] Holzkastenstützwand

timber crib cofferdam 木笼围堰 timber-crib breakwater 木笼式防波堤 rock-filled timber crib 填石木笼 rock-filled timber crib dam 填石木垛坝 filled timber crib 填石木垛 rockfill timber crib 叠木石笼 timber crib dam detail 木笼

Crib Cofferdam. A crib is a framework of wooden horizontal & cross beams. This cribs are open at the bottom and are filled with rock, gravel or earth. This type of cofferdam favorable where the bed of stream is hard, depth of water is high, water is swift. Cellular Cofferdam At its full weight, defendant's evidence as to individual faults in the cofferdam walls or inadequate and incomplete grouting, taken together with the leakage from the timber crib, could not account for the particular phenomena — connected boils on both sides of the cofferdam wall; a strong current between the boils; great resistance to. Cofferdams The cofferdam is a temporary structure, usually built in place, and tight enough so that the water can be pumped out of the structure and kept out while construction on the foundations is in progress. Common cofferdam types are earthen, steel sheeting, wooden sheathing, and crib. Figure 10-30 shows a cofferdam under construction diversion channel is protected by the contractor's cofferdam, Figure 3. The cofferdam con9ists of a rock-filled sheet piling and timber crib extending 110 feet downstream from the left wall of the channel, and an earth-fill dike extending from the crib to the old river channel about 220 feet farther downstream. The toe of the main dam forms th

  1. 3. Timber Crib : Constructed on land and floated into place. Lower portion of each cell is matched with contour of river bed. It uses rock ballast and soil to decrease seepage and sink into place, also known as Gravity Dam. It usually consists of 12'x12' cells and is used in rapid currents or on rocky river beds
  2. A cofferdam is defined as a temporary structure which is constructed so as to remove water from an area and make it possible to carry on the construction work under reasonably dry conditions. The materials used in the construction of a cofferdam are earth, timber, steel and concrete. 6) The cofferdam is generally Rock-filled crib.
  3. The crib is sunk into position, the internal space filled with stone or other material and timber or steel piles are then driven around the boundary of the crib. [ edit ] Cellular This type of cofferdam is most suitable for deep water areas , most commonly for during marine construction such as dams and wharves

Types of Cofferdams and Their Construction Details - The

A cofferdam is a temporary structure designed to keep water and/or soil out of the excavation in which a bridge pier or other structure is built. Timber Crib. Double-Walled Sheet Pile. Cellular. Braced Cofferdams. Formed from a single wall of sheet piling Timber crib dams and plank dams were common at this time. The crib dam was constructed of heavy timbers stacked like a log house and filled in with earth or rubble. An example of a Timber Crib Dam: Clevedon Hills, M5 - 1970. Crib walls have generally been developed outside the UK temporary sheetpile cofferdam during shoreline penetration and installation of the first 30 feet of pipe, dewatering through filter bags, use of turbidity curtains, limits to disturbance of the lakebed, and water The facility looked at upturned cone and timber crib intake options. It was determined that the upturned cone option is the best. Duxbury, VT: Installation of a temporary cofferdam and dewatering of the head pond to remove and replace the existing timber crib dam. Essex, VT: Over 3,000-square-feet of dam facing was repaired, including demolition and associated concrete work Chapter 13 COFFERDAMS 13.1. Introduction Cofferdams are temporary structures built in rivers, storage reservoirs, or the sea, to enable foundations to be built in dry foundation pits (Fig. 13.1). After a cofferdam is built, the pit is dewatered, the foundation is carried out, and the structure is concreted above the water level

Timber crib walling with planting | Landscape details

Cofferdam (Types Of Cofferdams And Types Caissons

SMCC extension - making the timber crib wall - YouTube

Cofferdams - an overview ScienceDirect Topic

  1. Timber piles. Concrete Piles. Steel Piles. Composite piles. Sand piles. Cofferdams: A Cofferdam is a transitory structure that bars the water from an offered site to construct a dry surface. Cofferdam. Classification Of Cofferdams Based On Material: Earthen Cofferdam. Rock-fill Cofferdam. Single-walled cofferdam. Double-walled cofferdam. Crib.
  2. This cofferdam has about 4,000 sf of sheet piles, so adding 0.6 psf adds only 2,400 lbs. At $0.10 per pound, that adds only about $240 to the cost of the cofferdam. If there is a concern that the soil conditions will cause sheet pile damage, it is better to use a heavier sheet pile
  3. Soo locks property with timber crib area near buidling (hydroelectric power plant) on the far left. One of the hydroelectric power plants at the Soo. Work area for the Soo crib dam repair project is near the center of the photo where the foot bridge ends
  4. ary plans and details for cofferdams and river diversion structures to remove not only the dam but also the sediment that had accumulated upstream of the dam. Materials removed included 13,000 cy of an original timber crib dam; 12,000 cy of roller-compacted concrete; and 20,000 cy of sediment immediately upstream of the dam
  5. Next, for the piers near Little Hell Gate, heavy-timber crib open-cofferdams were built, and the area within leveled and dried. Concrete for the foundation of the piers was poured into forms set within the dams. Granite veneer covers the 12 vertical feet between mean high and low tide levels to protect the concrete piers from wear due to rapid.
  6. Intake Dam was originally constructed as a rock-filled timber crib weir about 12 ft high and 700 ft long. The original dam contained 23,000 cubic yards of material. The dam raises the upstream water elevation from about three to five feet depending on river flows. Since the construction of Intake Dam, the structur

Timber crib weirs in Queenslan

The use of trade, firm, or corporation names in this publication is for the information and convenience of the reader. Such use does not constitute an official endorsement or approval by the U.S. Department of Agriculture of any product or service to the exclusion of others that may be suitable Timber crib dams were erected of heavy timbers or dressed logs in the manner of a log house and the interior filled with earth or rubble. The heavy crib structure supported the dam's face and the weight of the water. OTHER TYPES COFFERDAMS A cofferdam is a barrier, usually temporary, constructed to exclude water from an area that is. Removal or draining groundwater or surface water from a riverbed, construction site, caisson, or mine shaft by pumping or evaporation

Gateways to Commerce: The U

  1. Giải thích EN: 1. a structure of horizontally, cross-piled, squared timbers used to support a structure above.a structure of horizontally, cross-piled, squared timbers used to support a structure above.2. a structure composed of one or more layers of timber or steel joists, upon which a load may be spread.a structure composed of one or more layers of timber or steel joists, upon which a.
  2. Cofferdam installation and control of water during dam removal and limited construction access between the mill buildings were the major challenges at Paragon Mills Dam. Dyerville Dam was a deteriorated timber crib dam with limited access through the Groden Center parking lot
  3. Maritime Construction and Engineering, LLC 49 Pine Hill Rd, Cape Neddick, ME 03902 • Phone (207) 439-9831 • Fax (207) 439-9834 Owner: Town of York, ME Project: Rehabilitation of Town Dock #1 Cost: $585,380 Description: Demolition and replacement of a 5000 sqft timber commercial pier. Project included demolition/disposal of the existing pier, construction of a new concret
  4. 6.idenfity the corredt constructoin sequence for the construction of Diaphragm walls. a) Support the trench cutting using bentonite slurry. b) Inert reinforcement and placing of concrete to form the wall panel. c) Construct the guide wall. d) Excavation to form the diaphragm wall trench
Timber Crib Dam | Green River Timber Crib Dam at Gilford

Timber crib dams were erected of heavy timbers or dressed logs in the manner of a log house and the interior filled with earth or rubble. The heavy crib structure supported the dam's face and the weight of the water. Cofferdams. Main article: Cofferdam. A cofferdam during the construction of locks at the Montgomery Point Lock and Dam Tra cứu từ điển Anh Việt online. Nghĩa của từ 'rock fill' trong tiếng Việt. rock fill là gì? Tra cứu từ điển trực tuyến

Cofferdam Deep Foundation Civil Engineerin

Tie-ins to a sloping face are more complicated, with the most common solution involving timber bulkheads or timber cribs. Design. A cellular cofferdam's design is comparable to an anchored wall; however, because cofferdams consist of steel and soil, a rational design approach is difficult to achieve the cofferdam to allow pumping with minimal seepage through the forms. Timber Sheet Pile Driving Characteristics: A single or double row of timber sheet piling is sometimes used if only an earth bank is to be supported. Where water tightness is desired, or if earth pressures are large, some form of tongue and groove sheeting is preferable Circular cofferdam Figure eight cofferdam A.ch Arcs with struts. Cantilever Rock·filled timber crib with skìn of steel sheet piling Earth dam with steel sheet pile core Steel sheet piling supported by berms. Blockwork with skin of steel sheet pilin

Cofferdam - SlideShar

Rockfill Cofferdam. Rock-fill cofferdams are better than that of earthen dams. These dams are preferred when the rock is available easily at the construction site. These dams are very pervious, to. being used to supply Nicholasville, Kentucky with drinking water. The original dam is a timber crib structure, which helped sustain a seventeen and a half mile long pool of water.2 The original lock is made from stone masonry. The dam was constructed as an enclosure with a timber frame on the outside and dirt/rock on the inside Cofferdam - Any dam used to exclude water from a construction site. Most commonly constructed of steel sheets today. Column - A structural member carrying its load vertically. Creosote - Coal tar, heated and forced into timbers under pressure to act as a preservative. Crib - A heavy timber box often filled with stones, sand or mud

Cofferdam Deep Foundation Engineerin

The accident occurred around 4:30 p.m. on Dec. 10. Bisson and his co-workers were in a timber cofferdam trying to raise a sunken concrete crib when the cofferdam collapsed. Two doctors worked on Bisson after his body was recovered but he could not be revived. He was pronounced dead by drowning Timber used consists of rough logs They can supportin swift currents No danger of overtopping Concrete Cofferdams: Small concrete dams used economically on many jobs Pre cast RCC sheets and piles are used Disadvantage for temporary cofferdam: costly Suspended/movable Cofferdams: Single unit of coffer dam is used several times inside Sheet fillin • Timber Crib (257) • Other (1044) Oroville Dam (California) - 754 ft high. Earthfill Dams. Earthfill Dams Cofferdam (upstream and downstream) to seal off work area 3. Foundation work and build dam 4. Close diversion, remove cofferdam •Details vary greatly depending o Crib retaining walls, Bin retaining walls & Gabion Walls Nov 22, 2020 Vinod gopinath Retaining walls are rigid walls used for supporting soil laterally so that it can be retained at different levels o Timber piles. Concrete Piles. Steel Piles. Composite piles. Sand piles. Cofferdams: Crib Cofferdam. Cellular Cofferdam. Caisson Foundation: Caisson is a watertight structure made of wood, steel, or reinforced concrete that excavates for the foundation of bridges, piers, etc. This type of foundation is mostly used in bridge pier construction.

• Do not leave cofferdam or crib timber or bracing extending into the substructure concrete. • Place and cure seal concrete according to 00540.48(e). • Vent or port, at low water level, any cofferdam that is to remain in place. • Unless otherwise directed, remove cofferdams or cribs, including all sheeting an The east side excavation area with full view of river face of east side timber cofferdam, exposed rock wall on east... - NARA - 294158.jpg View from the west side of Block 40 showing concreting operations, timber crib construction and excavation of clay... - NARA - 294298.jp Steel cofferdams designed to 1:100 year flood and installed within work window, minimizing impact on fish habitat Structures were demolished and river bank was realigned; old timber crib retaining wall replaced with new reinforced concrete cantilever retaining wal

Use Big Bags USA Systems as a Coffer Dam!

maintained to limit flow and keep the timber cribbing underwater and saturated. Cap Coring and Exploration After the cofferdam was repaired and the water level within the cofferdam area was lowered, 4-inch diameter cores were taken through the concrete cap to determine the extent of the void. The intent was then to use thes Timber Dams: Main load-carrying structural elements of timber dam are made of wood, primarily coniferous varieties such as pine and fir. Timber dams are made for small heads (2-4 m or, rarely, 4-8 m) and usually have sluices; according to the design of the apron they are divided into pile, crib, pile-crib, and buttressed dams Cofferdams. Cofferdam is a temporary barrier constructed to exclude water from an area that is normally submerged. Made commonly of wood, concrete or steel sheet piling, cofferdams are used to allow construction on the foundation of permanent dams, bridges and similar structures. Timber crib dams were erected of heavy timbers or dressed. A cofferdam is a structure that retains water and soil that allows the enclosed area to be pumped out and excavated dry. Cofferdams are commonly used for construction of bridge piers and other support structures built within water. Cofferdams walls are usually formed from sheet piles that are supported by walers and internal braces, and

DAM DECOMMISSIONING: Removing Marmot Dam Hydro Revie

At the river end the excavation was, at some places, almost entirely through the fill and mud and was made in a cofferdam composed chiefly of sheet piles. As it was impossible to drive these piles across the old timber crib which formed the old dock front, the latter was cut through by a pneumatic caisson of wooden-stave construction, which. (5) Earth type It is the simplest type of cofferdam. It consists of an earth bank with a clay core or vertical sheet piling enclosing the excavation. It is used for low-level waters with low velocity and easily scoured by water rising over the top. (6) Timber crib Constructed on land and floated into place Rockfill Cofferdam: The depth of water to be retained by the embankment of the cofferdam is an order of 1.8 to 3m, stone or rubble is used for the embankment. Crib Cofferdam: In deep water wherever it is challenging to penetrate the guide piles or sheet piles within the hard bed below, crib cofferdam is used

timber cofferdam SpringerLin

During construction, an existing timber crib dam from the 1800s was uncovered while installing the HDPE pipeline on the lake bottom. Archeologists were called to the site and approvals from the State of Washington and the U.S. Forest Service was required before excavation could resume Cofferdams could be structurally classified into five different types; Braced, Earth-type, Timber crib, Double-walled sheet pile and Cellular cofferdams. The contractor usually carries out the design of cofferdams. In doing so, several factors are considered such as the sequence of construction, height Sheet pile wall types, construction methods, advantages and disadvantages are described in this article. Sheet-pile walls are widely used for both large and small waterfront structures, ranging from small pleasure-boat launching facilities to large dock structures where ocean-going ships can take on or unload cargo use in the cofferdam over this track. In order to fa-cilitate construction of the cofferdam when the stage of the river should become favorable, it was decided to frame the timber on the bank, so this work was started on May 10th. Actual construction of the cof-ferdam was started June 5th, when the first crib o Crib Retaining walls. Crib retaining wall or crib lock retaining wall is one of the oldest types of retaining wall. They consist of cribs or cells made of timber, concrete, and plastic/fibres. The cribs or interlock areas are filled with free-draining materials or earth back-fill, eliminating the hydro-static pressure and enabling a free escape.

Coffer dam and its type - SlideShar

In some first. Crib is then sunk into position to fit the variation of cases a ship is actually cut in two while still in the water, and a the surface of the bedrock. The cofferdam is removed after new section of the ship is floated in to lengthen the ship. Torch the concrete structure is completed above the water level temporary support crib wall elements, walkway assembly, lifeguard observation cabin, three reinforced concrete pipelines and existing utility conduits attached to the structure), and replace it with new buried discharge pipes and a concrete outlet structure supported on driven piles. A temporary cofferdam consisting of steel push-i Timber crib deterioration inaccessible for inspection. Strengthening the existing pier foundation with a concrete encasement around the timber cribs. This requires a special permanent cofferdam to. When cofferdams or foundation seals are required, submit working drawings and a complete description of the process as specified in Section 499. Timber or bracing left in the cofferdams or cribs shall not extend into the substructure concrete. Construct cofferdams in a manner that protects the concrete from damage. (a) Foundation Seal

3 Problematic soils Swelling soils giving tension on the

crib dam, and the creation of the new fish habitat in the coming months. Following this, the existing upstream and new downstream cofferdams will be removed and lake outflow will be redirected from the bypass channel to th INDEX 353 gravity dams, 205-206 thrust (see arch dams, thrust) hydrologic evaluation guidelines, 84 timber (table) facings, 216, 244-245 hydrometeorological method, 84-87 parapet walls, 247 site-specific determinations, 85, 87, 89 timber crib dams stability analyses, 205-206 deterioration, 19 stability analysis failures, 6 (table), 17 concrete. timber yield; timber-clad; timber-crib cofferdam; timber-crib control dam; timber-cutting and related occupations foreman; timber-floating; timber-frame house; timber-framed church; timber-framed house; timber-land; timber-line; timber-reliant community; timber-right; timber-splitting gun; timber-treating retort operator; timber-treating tank. Character of foundation: timber piling in clay. Kind of dam: fixed. Type of construction: timber crib. Date of completion: September 22, 1900. The accompanying Panorama View, Showing the Condition of the Work at the Close of the Season, Nov. 10, 1901 provides the full array of development in the vicinity of the lock and dam in its histori

Amid the increasing debate over dams, some dams are being removed for a variety of reasons. The Edwards Dam in Augusta, Maine, concerned local residents The timber crib enclosing the base of the pier was partly built on launching ways. floated to position and framed up to full height. A removable cofferdam in one section. used successively on different piers, was then picked up and placed on the crib. the crib sunk to the proper depth i No timber or bracing shall be left in the cofferdams in such a way as to extend into the substructure concrete, without written permission of the Department and Consultant. 1.5.5 Pumping of Water Pumping from the interior of any cofferdam shall be done in such a way as to preclude the possibility of the flow of water through any fresh concrete Timber crib structures. Repair or Replacement of up-stream or sluiceway sheathing. Penstocks and turbines, flash boards, stop logs. Installation of cofferdam, if installation is within existing service or emergency repair gains (i.e. upstream of operational stoplog gains) Đang xem: Crib là gì. crib /krib/ danh từ giường cũi (của trẻ con) lều, nhà nhỏ; nhà ở máng ăn (cho súc vật)(ngôn ngữ nhà trường) bài dịch để quay cóp (thông tục) sự ăn cắp văn (từ Mỹ,nghĩa Mỹ) thùng (đựng muối, ngô) cái đó (để đơm cá) giàn gỗ (đỡ thành giếng.

what is a cofferdam and its types - Civil4M