This document provides important guidelines for caring for bonsai plants, including avoiding choosing plants with large leaves, flowers, or fruits; using styles unsuitable for the species; using blunt cutting tools; unnatural decorations; being impatient for flowers or fruits before shaping; mixing chemicals and fertilizers; keeping bonsai on the ground; tying wire too tightly; retaining wires too long; hard pruning of conifers; heavy fertilization; and unnatural appearances.
Choose plants suitable for the local climate and position them correctly in containers with adequate drainage. Care for bonsai by pruning regularly, providing balanced nutrition with fertilizer, plenty of sunshine, and thorough watering until it drains. Inspect frequently for pests and diseases, and develop a natural-looking design that is well-balanced through constant care and affection.
Planting times for certain crops are February through March and July through August. Seeds can be sown in early spring from February to March or during the summer months from July to August.
The document discusses a demonstration on Juniper bonsai trees that will take place in Columbia. Juniper bonsai are a popular type of bonsai tree that can be styled and shaped through careful pruning and training. The demonstration will cover basic bonsai techniques for caring for and maintaining Juniper bonsai trees.
This document lists the essential equipments and tools needed for bonsai, which includes a plant, pots of various shapes with drainage holes, a potting mixture of soil, sand and leaf mould, potting sticks, sieves, copper wire of varying thickness, wire cutters, pruning knives and secateurs, and watering equipment like a can and tub.
This document lists important plant species for growing bonsai in hilly areas, including Araucaria, Aucuba, Azalea, Camellia, Chinese hat, Coral tree, Cryptomeria, Cypress, Flame of the forest, Ginkgo, Juniper, Koelreuteria, Maple, Magnolia, Plane tree, Peach, Pines, Podocarpus, Sal, Silver fir, Spruce, Taxus, Thuja, Willows, and Zanthoxylum.
This document lists important plant species that are suitable for bonsai, including trees, shrubs, and bamboo. Some recommended species are amaltas, araucaria, babul, bamboo, banyan, ber, bottle brush, bougainvillea, casuarina, cherry, Chinese orange, coranda, cryptomeria, deodar, duranta, excoecaria, gulmohar, hibiscus, ixora, jacaranda, Java fig-tree, murraya, malpighia, oleander, peach, pines, pilkhan, pipal, plum, prosopis, silver oak, tamarind.
Propagation of plants can be done through seeds, cuttings, layering, grafting, or buying seedlings from a nursery. Some plants can also be propagated through collection from seeds or cuttings found in forests or fields.
Selection of plants for bonsai requires choosing species that can thrive in confined spaces with minimal resources. Good options are plants with small flowers and fruits that allow foliage to reduce to a quarter of its normal size, or those bearing flowers on leafless branches. The selected plant must be able to withstand stress from a small pot and low nutrients.
Pruning and trimming helps develop trees into attractive shapes by restricting growth and maintaining a proper balance between roots and shoots. It involves regularly cutting no more than 1/3 of roots or shoots to reduce growth in a controlled manner. Proper pruning techniques help develop good structure and form for trees.
Ideal nutrition for bonsai includes sludge or well rotten cow dung slurry mixed with groundnut, cotton, or neem cake allowed to ferment for a month before diluting. This mixture is given twice a month along with bone meal and single super phosphate, which are also very beneficial.
Growing media for bonsai should be coarse and well-drained to provide water, oxygen, and nutrients. An ideal medium consists of equal parts soil, leaf mold, and crushed brick or sand. The top layer needs sufficient humus, while conifer plants do better in drier soil and fruit trees prefer more humus-rich soil.
This document discusses a landscaping style using cascading plants with variegated star jasmine. Cascade style landscaping features plants hanging over walls or spilling out of containers to create a sense of movement. Variegated star jasmine is recommended as it has green and white variegated leaves and fragrant white flowers that bloom throughout the summer. This combination provides visual interest and fragrance.
This document provides important guidelines for caring for bonsai plants, including avoiding choosing plants with large leaves, flowers, or fruits; using styles unsuitable for the species; using blunt cutting tools; unnatural decorations; being impatient for flowers or fruits before shaping; mixing chemicals and fertilizers; keeping bonsai on the ground; tying wire too tightly; retaining wires too long; hard pruning of conifers; heavy fertilization; and unnatural appearances.
Choose plants suitable for the local climate and position them correctly in containers with adequate drainage. Care for bonsai by pruning regularly, providing balanced nutrition with fertilizer, plenty of sunshine, and thorough watering until it drains. Inspect frequently for pests and diseases, and develop a natural-looking design that is well-balanced through constant care and affection.
Planting times for certain crops are February through March and July through August. Seeds can be sown in early spring from February to March or during the summer months from July to August.
The document discusses a demonstration on Juniper bonsai trees that will take place in Columbia. Juniper bonsai are a popular type of bonsai tree that can be styled and shaped through careful pruning and training. The demonstration will cover basic bonsai techniques for caring for and maintaining Juniper bonsai trees.
This document lists the essential equipments and tools needed for bonsai, which includes a plant, pots of various shapes with drainage holes, a potting mixture of soil, sand and leaf mould, potting sticks, sieves, copper wire of varying thickness, wire cutters, pruning knives and secateurs, and watering equipment like a can and tub.
This document lists important plant species for growing bonsai in hilly areas, including Araucaria, Aucuba, Azalea, Camellia, Chinese hat, Coral tree, Cryptomeria, Cypress, Flame of the forest, Ginkgo, Juniper, Koelreuteria, Maple, Magnolia, Plane tree, Peach, Pines, Podocarpus, Sal, Silver fir, Spruce, Taxus, Thuja, Willows, and Zanthoxylum.
This document lists important plant species that are suitable for bonsai, including trees, shrubs, and bamboo. Some recommended species are amaltas, araucaria, babul, bamboo, banyan, ber, bottle brush, bougainvillea, casuarina, cherry, Chinese orange, coranda, cryptomeria, deodar, duranta, excoecaria, gulmohar, hibiscus, ixora, jacaranda, Java fig-tree, murraya, malpighia, oleander, peach, pines, pilkhan, pipal, plum, prosopis, silver oak, tamarind.
Propagation of plants can be done through seeds, cuttings, layering, grafting, or buying seedlings from a nursery. Some plants can also be propagated through collection from seeds or cuttings found in forests or fields.
Selection of plants for bonsai requires choosing species that can thrive in confined spaces with minimal resources. Good options are plants with small flowers and fruits that allow foliage to reduce to a quarter of its normal size, or those bearing flowers on leafless branches. The selected plant must be able to withstand stress from a small pot and low nutrients.
Pruning and trimming helps develop trees into attractive shapes by restricting growth and maintaining a proper balance between roots and shoots. It involves regularly cutting no more than 1/3 of roots or shoots to reduce growth in a controlled manner. Proper pruning techniques help develop good structure and form for trees.
Ideal nutrition for bonsai includes sludge or well rotten cow dung slurry mixed with groundnut, cotton, or neem cake allowed to ferment for a month before diluting. This mixture is given twice a month along with bone meal and single super phosphate, which are also very beneficial.
Growing media for bonsai should be coarse and well-drained to provide water, oxygen, and nutrients. An ideal medium consists of equal parts soil, leaf mold, and crushed brick or sand. The top layer needs sufficient humus, while conifer plants do better in drier soil and fruit trees prefer more humus-rich soil.
This document discusses a landscaping style using cascading plants with variegated star jasmine. Cascade style landscaping features plants hanging over walls or spilling out of containers to create a sense of movement. Variegated star jasmine is recommended as it has green and white variegated leaves and fragrant white flowers that bloom throughout the summer. This combination provides visual interest and fragrance.
1. Chương 3.
KÉO (NÉN) ĐÚNG TÂM
3.1. Khái niệm về kéo (nén) đúng tâm, lực dọc và biểu đồ lực dọc
3.1.1. Khái niệm về kéo ( nén) đúng tâm
Trong chương này ta sẽ nghiên cứu trường
hợp chịu lực đơn giản nhất của thanh thẳng là khi
thanh chịu kéo hoặc nén đúng tâm.
Khi ta tác dụng vào các đầu thanh hai lực
song song ngược chiều, có phương trùng với
phương của trục thanh và có trị số giống nhau, ta
sẽ có:
a)
P P
P P
- Hoặc thanh chịu kéo đúng tâm nếu lực hướng ra khỏi mặt cắt (hình 3.1a).
- Hoặc thanh chịu nén đúng tâm nếu lực hướng vào mặt cắt hình (3.1b).
Từ đó ta có định nghĩa: “Thanh chịu kéo (nén) đúng tâm khi trên mọi mặt cắt ngang
của thanh chỉ có một thành phần lực dọc Nz”.
Dưới đây ta sẽ nghiên cứu nội lực phát sinh trong thanh chịu kéo (nén) đúng tâm.
3.1.2. Lực dọc - biểu đồ lực dọc
a). Lực dọc:
Giả sử xét một thanh chịu kéo đúng tâm bởi lực P. Để tính nội lực tại mặt cắt bất kỳ
của thanh ta thường dùng phương pháp mặt cắt (hình 3.2).
Tưởng tượng cắt thanh tại mặt cắt 1-1, xét cân bằng phần A.
Muốn cho phần A cân bằng, thì hợp các nội lực trên mặt phải là nội lực N đặt tại
trọng tâm mặt cắt và trùng với trục thanh. Lực N
đó gọi là lực dọc.
Trị số lực dọc N được xác định từ điều kiện cân
bằng tĩnh học của phần A (hoặc phần B), là tổng
hình chiếu của các lực tác dụng lên phần đang xét
xuống phương trục thanh (trục z) phải bằng không:
b)
H×nh 3.1
P P
a)
b)
1
A B
1
P Nz z
A F
H×nh 3.2