The Pavilion
In October 2022, an exceptional bamboo structure emerged from the Geeli Mitti workshop – “The Pavilion.” This captivating unique structure is conceived as an outdoor workspace, offering a serene setting enveloped by lush greenery and the soothing symphony of a nearby stream. The Pavilion, occupying a generous 343 square feet and soaring to a majestic height of 17 feet, stands proudly on a naturally contoured landscape, thoughtfully divided into three functional levels.
Diverse Bamboo Species
The Pavilion owes its strength and sustainability to an assortment of bamboo species, each meticulously selected for its unique structural properties. Notably, Dendrocalamus Giganteus and Dendrocalamus Asper, renowned for their robust characteristics and impressive diameters ranging from 4 to 11 inches, form the backbone of this bamboo wonder. Additionally, Assamese Bamboo, also known as Bambusa Tulda, with a diameter of 3-4 inches, contributes significantly to its structural framework.
Traditional Lashing Techniques
What truly sets The Pavilion apart is its exclusive reliance on traditional bamboo lashing techniques for construction. These time-honoured techniques include Square Lashing, Diagonal Lashing, Parallel/Shear Lashing, Round Lashing, Tripod Lashing, and T Lashing with a peg. Jute Rope, recognized for its commendable tensile strength, serves as the chosen material for securely binding the bamboo components together. With tensile strength ranging from 200 to 400 N/mm², jute rope emerges as a dependable choice for this purpose.
At the first level, the structure is supported by a stone slate flooring, with six vertical members of the Dendrocalamus Giganteus Bamboo species serving as the primary load-bearing columns. Dendrocalamus Giganteus boasts an impressive compressive strength of up to 78 Mpa. These six columns are interconnected through an arch crafted from Lidi Bundles, which are made from 8 split bamboos sourced from Dendrocalamus Asper. These bamboo splits have excellent flexibility, allowing the arching system to be easily shaped, capitalizing on bamboo’s remarkable tensile strength to construct robust yet lightweight structures.Â
The assembly of hand-whittled bamboo splits tied together is known as a Lidi Bundle. This results in a curved and flexible arch that can be adjusted in shape, giving rise to an organic curvilinear structure. The Lidi bundles are meticulously hand-tied on the ground and secured tightly using round lashing to ensure their cohesion. Once assembled, the bundles are transported to the site and affixed to the primary load-bearing bamboo columns using parallel shear lashing on the sides and round lashing on top.
Horizontal members, Assamese bamboo, are placed atop the
columns to act as beams, ensuring even distribution of loads to the columns. To
secure these beams and columns, a T lashing technique is employed, featuring a
peg inserted into the DG bamboo column.
The sloping roof frames are constructed from half-split Assamese bamboos, strategically tied together. Two horizontally running purlins are secured to four vertically running rafters using the square lashing method, forming a sturdy rectangular frame. Additionally, five common rafters are placed diagonally on this frame and fastened using diagonal lashing, serving as supporting members to ensure efficient weight distribution. The roofing frame is initially assembled on the ground and later affixed to the structure, connecting to the existing beams and columns through diagonal and tripod lashing techniques. A transparent polycarbonate sheet is added on top of the roof to protect it from columns to act as beams, ensuring even distribution of loads to the columns. To secure these beams and columns, a T lashing technique is employed, featuring a peg inserted into the DG bamboo column.
Level 2 is situated with a two-foot elevation from Level 1, and both levels are connected laterally through intersecting Lidi bundles, secured with parallel/shear lashing at the base and diagonal lashing at the top. Similar to Level 1, this level stands on a stone slate flooring, supported by six vertical members of the Dendrocalamus Asper Bamboo species acting as the primary load-bearing columns, boasting a compressive strength of up to 65 Mpa. These columns are also interconnected with an arch constructed from Lidi Bundles, fashioned from 8 split bamboos from Dendrocalamus Asper.
Horizontal members, again made of Assamese bamboo, are positioned atop the columns to distribute loads evenly. The T lashing technique, with a peg inserted into the DA bamboo column, is used to securely fasten the beams and columns, which serve as the primary load-bearing elements.
The sloping roof frames feature half-split Assamese bamboos strategically tied together. Two horizontally running purlins are attached to four vertically running rafters using the square lashing method, forming an efficient rectangular frame. The roof thatch consists of four split bamboo shingles affixed to the horizontally running splits across the roof. These bamboo shingles facilitate rainwater drainage, preventing leaks into the structure.
Level 3, situated 6 feet above Level 2, features a foundation resting on a stone slate flooring. Here, four vertical members of the Assamese Bamboo species act as the primary load-bearing columns, offering a compressive strength of up to 40 Mpa.
Like the lower levels, horizontal members made of Assamese bamboo are placed atop the columns to act as beams, ensuring even load distribution. The T lashing technique, involving the insertion of pegs into the Assamese bamboo columns, is used to securely fasten the beams and columns.
Supporting the roof on Level 3 are three trusses: one at each end and one in the centre, all tied to the ridge running along the roof for efficient weight distribution. These trusses form an inverted T-shaped structure. The vertical member of the truss, known as the king post, is fastened to the ridge using the T lashing technique, with pegs inserted into the bamboo. The horizontal member, serving as the tension member, is tied to the beam using the T lashing technique, with pegs inserted into the bamboo at both ends and a simple T lashing technique in the centre, ensuring efficient load support.
The sloping roof frame is composed of half-split Assamese bamboo, serving as rafters. Vertically running split bamboo members are tied to these rafters using a simple lashing technique. To complete the roof, a thatch crafted from dried sugarcane leaves is incorporated. It is widely recognized that a dried sugarcane thatch typically has a lifespan of 5 to 6 years.
The Pavilion represents a remarkable fusion of Bamboo Architecture Design and modern construction techniques, showcasing the potential of bamboo as a construction material in creating sustainable, environmentally friendly structures that blend harmoniously with the natural surroundings.
